Difference between revisions of "Deuces"

From BRL-CAD
(new QA task)
(Complete our "Intro to BRL-CAD Modeling" tutorial and extend it)
 
(151 intermediate revisions by 20 users not shown)
Line 1: Line 1:
This is a list of really quick projects that are expected to take most people less than two hours to complete.  It's a great starting point for any new contributor that would like to work on BRL-CAD.
+
Below are tasks that are a great starting point for anyone interested in contributing to BRL-CAD. Most tasks can be completed in just a couple hours!  '''''No prior experience with BRL-CAD is required.''''' 
  
These tasks are all roughly the same complexity with '''''no prior BRL-CAD experience expected'''''For all tasks, a description is provided along with helpful references and a list of files you'll probably need to edit.  Can we make it any easier?
+
Some tasks may take longer if you aren't set up or haven't done that type before, but all they all require about the same amount of experienced effortEach task has a description, references, and list of files you'll probably need.  Can we make it any easier? [https://brlcad.zulipchat.com Let us know].
  
= Getting Started =
+
= Get Set Up =
  
Please do contact us (via [[IRC]] or [[Mailing_Lists|brlcad-devel mailing list]]) if you have any questions, corrections, comments, or ideas of your own that you'd like to suggest.
+
We suggest you [[Compiling|compile BRL-CAD]] yourself or, if you have trouble with that, there's a virtual image with everything preconfigured, ready to go:
  
We've made a really awesome virtual disk image that has everything you need included, preconfigured, and ready to be edited.  Here's what you do:
+
# [https://sourceforge.net/projects/brlcad/files/BRL-CAD%20for%20Virtual%20Machines/ Download our BRL-CAD Virtual Machine (VM) disk image.]
# [https://sourceforge.net/projects/brlcad/files/BRL-CAD%20for%20Virtual%20Machines/ Download our image]
+
# [https://www.virtualbox.org/wiki/Downloads Install VirtualBox.]
# [https://www.virtualbox.org/wiki/Downloads Download and run VirtualBox]
+
# Import the disk image, start the VM, and log in (password is "Brlcad!" without quotes).
# Get started [[Compiling|compiling]]!
+
# Run "svn up brlcad-svn-trunk" and [[Compiling#Configure_your_Build|compile]].
 +
 
 +
= Pick a Task =
 +
 
 +
Once set up, select any task that sounds interesting, read the references, and [https://brlcad.zulipchat.com talk with us] for help.  Don't worry if some words are confusing.  You got this.  All tasks can be completed by '''''anyone''''' but are grouped into the following five interest categories:
 +
 
 +
* Code (programming)
 +
* Documentation and Training (technical writing)
 +
* Outreach and Research (graphics, marketing)
 +
* Quality Assurance (testing)
 +
* User Interface (usability, design)
  
 
__TOC__
 
__TOC__
  
----
 
  
= Code =
+
== Code ==
----
 
 
''Tasks related to writing or refactoring code''
 
''Tasks related to writing or refactoring code''
  
== Move comments from source to header files ==
+
See the When You're Done section above for details on submitting your changes.
 
 
BRL-CAD uses Doxygen source code comments to document the API.  The comments need to be moved from .c source code files to the corresponding .h API header file.
 
  
This task involves editing source code to move comments and verifying compilation wasn't broken in the process.  See each library below for details.
 
  
=== ... move LIBBN comments ===
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Close MGED only when both windows are closed ===
  
There are less than 150 API comments across 17 files in LIBBN that need to be movedThis will find most of them:
+
BRL-CAD has an interactive geometry editor called MGEDIt's often the starting point for beginners and allows creation and manipulation of models using commands. When ''mged'' is run, it creates 2 windows:  a text console for commands and an interactive graphics window.  Currently, if you close the graphics window, it quits the application.
  grep -n -r -E '^/\*\*$' src/libbn | grep -v svn | grep -v '\*\*\*' | grep -v '@'
 
  
Move all the comments that have a corresponding BN_EXPORT declaration in the include/bn.h header. It should take less than 30 seconds to review each one.
+
This task involves change behavior so that MGED exits only after closing ''both'' windows.  Closing just the graphics window or text console should not quit MGED.
  
 
Code:
 
Code:
* include/bn.h
+
* src/mged/mged.c
* src/libbn/*.c
+
* src/tclscripts/mged/openw.tcl
 +
* src/tclscripts/mged/bindings.tcl
  
=== ... move LIBRT comments for files beginning with the letter 'd' ===
+
 
 +
|}
 +
 
  
There are approximately 143 public API comments in LIBRT files starting with a 'd' (e.g., src/librt/db_tree.c) that need to be moved.  This will find most of them:
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
grep -n -r -E '^/\*\*' src/librt | grep -v svn | grep -v '\*\*\*' | grep -v '@' |grep 'librt/d'
+
| style="padding: 20px;" |
 +
=== Implement a primitive centroid function ===
  
Move all the comments that have a corresponding RT_EXPORT declaration in the include/raytrace.h headerIt should take less than 30 seconds to review each one.
+
BRL-CAD provides more than two dozen types of geometry "primitives" such as ellipsoids, boxes, and cones.  Every primitive is described by a collection of callback functions, for example rt_'''ell'''_bbox() returns the bounding box dimensions for an '''ell'''ipsoidWikipedia, Wolfram Mathworld, and various other math sites (and research papers) around the web include the equations for most of our basic primitives while others are more tricky to compute.
  
Code:
+
This task involves writing a new callback function that takes an rt_db_internal object and calculates its centroid (as a point_t 3D point). There are numerous examples in our code where we compute centroids for other primitives. The primitives that do not already have a centroid callback are itemized in following.
* include/raytrace.h
 
* include/db.h
 
* include/db5.h
 
* src/librt/d*.c
 
  
=== ... move LIBRT comments for files beginning with a-c and e-o ===
+
References:
 
+
* http://en.wikipedia.org/wiki/Centroid
There are approximately 150 public API comments in LIBRT files starting with 'a', 'b', 'c', (notice we skip 'd' files) 'e', 'f', ... 'n', and 'o'.  This will find most of them:
+
* http://mathworld.wolfram.com/
grep -n -r -E '^/\*\*' src/librt | grep -v svn | grep -v '\*\*\*' | grep -v '@' |grep 'librt/[abcefghijklmno]'
+
* include/raytrace.h: See ft_centroid callback defined in the rt_functab structure
 
 
Move all the comments that have a corresponding RT_EXPORT declaration in the include/raytrace.h header.  It should take less than 30 seconds to review each one.
 
  
 
Code:
 
Code:
* include/raytrace.h
+
* src/librt/primitives/table.c
* include/db.h
+
* src/librt/primitives/[PRIMITIVE]/[PRIMITIVE].c
* include/db5.h
 
* src/librt/[abcefghijklmno]*.c
 
* src/librt/comb/*.c
 
* src/librt/binunif/*.c
 
  
=== ... move LIBRT comments for files beginning with 'q' through 'z' ===
+
 
 +
|}
 +
 
  
There are approximately 106 public API comments in LIBRT files starting with 'q' through the letter 'z'  This will find most of them:
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
grep -n -r -E '^/\*\*' src/librt | grep -v svn | grep -v '\*\*\*' | grep -v '@' |grep 'librt/[q-z]'
+
| style="padding: 20px;" |
 +
=== Implement a primitive curvature function ===
  
Move all the comments that have a corresponding RT_EXPORT declaration in the include/raytrace.h header.  It should take less than 30 seconds to review each one.
+
BRL-CAD provides more than two dozen types of geometry "primitives" such as ellipsoids, boxes, and cones each described by a collection of callback functions, for example rt_'''sph'''_bbox() returns the bounding box dimensions for a '''sph'''ere.  Wikipedia, Wolfram Mathworld, and various other math sites (and research papers) around the web include the equations for most of our basic primitives while others are a little more tricky to compute.
  
Code:
+
This task involves writing the callback function rt_xxx_curve() that computes the curvature at a given point on the surface of a primitive such as;
* include/raytrace.h
+
* superell
* include/db.h
+
* cline
* include/db5.h
+
* extrude
* src/librt/[q-z]*.c
+
* grip
 +
* metaball
 +
* hrt. 
 +
There are numerous examples in our code where we compute the curvature for other primitives like the ellipsoid, sphere, elliptical parabola, etc.
  
=== ... move LIBWDB comments ===
+
References:
 
+
* http://en.wikipedia.org/wiki/Curvature
There are approximately 60 public API comments in LIBWDB files.  This will find most of them:
+
* http://en.wikipedia.org/wiki/Radius_of_curvature_(mathematics)
grep -n -r -E '^/\*\*' src/libwdb | grep -v svn | grep -v '\*\*\*' | grep -v '@'
+
* http://mathworld.wolfram.com/
 
+
* include/raytrace.h: See the data structure that holds the curvature of a surface at a point (from Line 296) as well as the prototype for ft_curve() callback function defined in the rt_functab structure ( Line 2078).
Move all the comments that have a corresponding WDB_EXPORT declaration in the include/wdb.h header AND stub in placeholder /** */ comments for any declarations in the header still lacking a comment block.  ALSO, remove any 'F U N C T I O N' names that are spaced out from the comments.
 
  
 
Code:
 
Code:
* include/wdb.h
+
* src/librt/primitives/table.c
* src/libwdb/*.c
+
* src/librt/primitives/[PRIMITIVE]/[PRIMITIVE].c
  
== Close MGED when both its windows are closed ==
+
 
 +
|}
 +
 
  
BRL-CAD has an interactive geometry editor called MGED. It's often the starting point for beginners and allows creation and manipulation of models using commands. When MGED is invoked, it creates 2 windows: a text-console command window and an interactive graphics window.  When the user closes one of those windows, there is a bug.  Closing the graphics window closes the command window.  Even if both windows are manually closed, the MGED process is not terminated.
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Implement a primitive UV-mapping callback ===
  
This task involves fixing this behavior so that ONLY closing ''both'' windows terminates the process properly and that closing either window does not take the other along with it.
+
BRL-CAD provides more than two dozen types of geometry "primitives" such as ellipsoids, boxes, and cones.  Every primitive is described by a collection of callback functions, for example rt_'''ell'''_bbox() returns the bounding box dimensions for an '''ell'''ipsoid.  One of those functions describes a UV mapping of the object's surface, which is used for things like texture and bump mapping.  An example of this is rt_ell_uv() in the src/librt/primitives/ell/ell.c source file for an ellipsoid.  Several of our more complex primitive types (such as BoT, NMG, and BREP/NURBS) do not presently implement a UV-mapping function leading to unexpected runtime behavior.
  
Code:
+
This task involves implementing a UV-mapping callback for any of the primitives that do not already have a functional UV-callback defined. Note that this is an advanced task that might take you more than a couple hours if you don't have solid coding skills, but it's ultimately just a few lines of code.  See other primitives that already implement a UV-mapping callback for reference.
* src/mged/mged.c
 
* src/tclscripts/mged/openw.c
 
  
== Implement parallel support for Windows ==
+
References:
 
+
* http://en.wikipedia.org/wiki/UV_mapping
BRL-CAD works pervasively on symmetric multiprocessing (SMP) systems, i.e. computers with multiple CPUs or cores. However, support for SMP is implemented for each distinct platform.  BRL-CAD runs on Windows, but presently only in a single-threaded mode.  To make it work in parallel, we need to define how threads are created (e.g., CreateThread()) and how to acquire a threading lock.
+
* src/librt/primitives/[PRIMITIVE]/[PRIMITIVE].c, search for rt_*_uv() functions
 
 
This task involves implementing the hooks necessary to make BRL-CAD work in parallel on Windows.  This can be achieved with relatively minor source code modifications to two files.
 
  
 
Code:
 
Code:
* src/libbu/parallel.c
+
* src/librt/primitives/extrude/extrude.c
* src/libbu/semaphore.c
+
* src/librt/primitives/table.c
 
+
* include/rtgeom.h
== Decouple LIBDM from LIBGED ==
 
 
 
BRL-CAD has a 3D display manager library (LIBDM) and a geometry editor command library (LIBGED).  For clean encapsulation and library management, it's desirable to keep library dependencies to a minimum.  LIBGED presently makes direct calls to LIBDM for a "screengrab" command.  Properly fixed, it should be possible to remove the LIBDM linkage from LIBGED's build file and the command still work as expected.
 
  
This task involves breaking the dependency of LIBGED on LIBDM by making LIBGED not directly call any LIBDM functions.  To do this, LIBGED will need to introduce a callback mechanism in the "ged" struct so that the screengrab command can capture an image without directly calling a LIBDM function.
+
 
 +
|}
 +
 
  
Code:
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
* include/ged.h
+
| style="padding: 20px;" |
* include/dm.h
+
=== Debug and fix a bug converting cylinders ===
* src/libged/screengrab.h
 
* src/libged/CMakeLists.txt
 
  
== Implement runtime detection of SSE ==
+
BRL-CAD has many 3D object types, one of them being a "Right Hyperbolic Cylinder".  If you run MGED with "mged -c cylinder.g", then run "make rhc rhc" on the mged> command prompt, it will create one.  If you then quit mged and run "dbupgrade -r cylinder.g" and reopen the file with "mged -c cylinder.g", the rhc object will be corrupted (try running "l rhc" in mged before and after).
  
BRL-CAD will optionally leverage SSE instructions for some operations but SSE-support is set at compile-timeIf you attempt to perform SSE instructions on non-SSE hardware, it'll basically halt the application with an illegal instruction exception.  That's a fancy way of saying it crashes.
+
This task's goal is to reproduce, identify, and fix the bug so that the rhc object doesn't get corruptedTo do this, you'll want to use a debugger like lldb or gdb or Visual Studio (there are tutorials all over the web if you've never used a debugger), or simply use print statements.
  
This task involves implementing a function (that will go into our LIBBU utility library) to reports whether SSE support is available at runtime. The most prevalent method for doing this is demonstrated by the Mesa folks where you set up an exception handler for SIGILL and attempt an SSE instruction. That's obviously a non-solution for Windows platforms, but is better than nothing and more useful than a Windows-only solution. Even better if you can handle both or implement a cross-platform solution. You'll implement a bu_sse_init() function that returns an error if SSE is not available at runtime.
+
See the rt_rhc_import5(), ..export5(), .._import4(), and .._export4() functions as they implement the read/write support.  
  
 
Code:
 
Code:
* include/bu.h
+
* src/librt/primitives/rhc/rhc.c, <- you'll probably need to modify this file
* src/libbu/sse.c
+
* src/librt/primitives/table.c
 +
* include/rtgeom.h
  
== Fix bounding box function for our polygonal mesh (BoT) primitive ==
+
&nbsp;
 +
|}
 +
&nbsp;
  
BRL-CAD provides functions for its geometric primitives that define a bounding box - a box that completely encloses the volume described by the primitive.  Ideally, these boxes are as small as possible while still enclosing the primitive.  Currently the routine for BoTs is incorrect.
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Fix elliptical torus triangulation ===
  
This task involves studying the current code for the function rt_bot_bbox() and determining what is causing the current inaccuracies (the bb command is a good way to visualize primitive bounding boxes) and making changes to produce a more optimal bounding boxThe raytracing prep code in rt_bot_prep does prepare a better bounding box, so that is one place to check.
+
BRL-CAD has many 3D object types, one of them being an "Elliptical Torus"If you create a new MGED database and run this sequence of commands, it'll crash due to excessive recursion:
  
Code:
+
<pre>
* src/librt/primitives/bot/bot.c
+
make eto eto
 +
tol norm 1
 +
facetize eto.bot eto
 +
</pre>
  
== Make mged 'tables' command not call system() ==
+
This task's goal is to reproduce, identify, and fix the bug so that detailed eto tessellation completes successfullyTo get started, see the rt_eto_tess() function in src/librt/primitives/eto/eto.c and the facetize command logic in libged.
 
 
BRL-CAD's geometry editor (MGED) provides hundreds of functions that users can call on the command line.  One of our oldest commands writes data out to text files and calls the unix "sort" command to sort a list of items.That's really bad.
 
 
 
This task involves replacing the three calls to system() with a call to quicksort() or any other simple in-memory sorting mechanism.
 
  
 
Code:
 
Code:
* src/libged/tables.c
+
* src/librt/primitives/eto/eto.c, <- you'll probably need to modify this file
 
+
* src/libged/facetize/facetize.cpp
== Separate LIBNURBS files into one class per file ==
 
 
 
BRL-CAD has a recently implemented a new library that isn't very well organized.  One of the complexities working on the sources are that the files do not group classes and functions together.  It's a bit of a mess.
 
  
This task involves cleaning up the library by making sure there is not more than one struct or class per source file.  Class/struct declarations should be in header files.  Class/struct definitions should be in source files.  Headers should be fully self-sufficient.  Rename the files while you're at it so they're all consistently named.  Be sure to update the CMakeLists.txt build file and test compilation.
+
&nbsp;
 +
|}
 +
&nbsp;
  
Code:
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
src/libnurbs/*
+
| style="padding: 20px;" |
 +
=== Implement a function that evaluates volume with spherical sampling ===
  
== Implement a primitive UV-mapping callback ==
+
Implement this function:
  
BRL-CAD provides more than two dozen types of geometry "primitives" such as ellipsoids, boxes, and cones.  Every primitive is described by a collection of callback functions, for example rt_ell_bbox() returns the bounding box dimensions for an ellipsoid.  One of those functions describes a UV mapping of the object's surface, which is used for things like texture and bump mapping.  An example of this is rt_ell_uv() in the src/librt/primitives/ell/ell.c source file for an ellipsoid.  Several of our more complex primitive types (such as BoT, NMG, and BREP/NURBS) do not presently implement a UV-mapping function leading to unexpected runtime behavior.
+
    int estimate_volume(struct db_i *dbip,  
 +
                        struct directory *dp,
 +
                        size_t min_samples,
 +
                        double confidence);
  
This task involves implementing a UV-mapping callback for any of the primitives that do not already have a functional UV-callback defined.
+
For this function, you'll want to read up on some of BRL-CAD's basic data structures by looking at headers in the include/rt directory or by reading our [https://brlcad.org/docs/api/ API documentation].  Calling rt_db_internal() and rt_bound_internal() will get you the bounding box around geometry from which you can calculate a bounding sphere.  Once you have the bounding sphere, randomly generate a set of min_samples*2 points on the surface of the sphere.  Shoot a ray through those points using rt_shootray(), as in the ray tracing [[Example_Application|example]].  Keep track of a volume estimate and keep shooting sets of min_samples rays until the estimate is less than the specified confidence value.  Volume of a sphere is (4/3 * pi * r^3) so dividing that by num_samples will give a per-ray factor and multiplying all hit thicknesses by that factor will give a running volume estimate.
  
 
References:
 
References:
* http://en.wikipedia.org/wiki/UV_mapping
+
* https://brlcad.org/docs/api/
 +
* https://brlcad.org/wiki/Example_Application
 +
* https://stackoverflow.com/questions/9600801/evenly-distributing-n-points-on-a-sphere
 +
* https://karthikkaranth.me/blog/generating-random-points-in-a-sphere/
  
Code:
+
&nbsp;
* src/librt/primitives/[PRIMITIVE]/[PRIMITIVE].c
+
|}
* src/librt/primitives/table.c
+
&nbsp;
* include/rtgeom.h
 
  
=== ... UV-mapping for extruded bitmap objects (EBM) ===
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
=== ... UV-mapping for extruded 2D sketch objects (EXTRUDE) ===
+
| style="padding: 20px;" |
=== ... UV-mapping for gridded volumes (VOL) ===
 
=== ... UV-mapping for N-faced arbitrary polyhedrons (ARBN) ===
 
=== ... UV-mapping for superellipsoids (SUPERELL) ===
 
=== ... UV-mapping for triangle meshes (BOT) ===
 
=== ... UV-mapping for solid polygonal meshes (NMG) ===
 
  
== Implement a primitive surface area function ==
+
=== Implement a function to return an object's color ===
  
BRL-CAD provides more than two dozen types of geometry "primitives" such as ellipsoids, boxes, and cones.  Every primitive is described by a collection of callback functions, for example rt_ell_bbox() returns the bounding box dimensions for an ellipsoidWikipedia, Wolfram Mathworld, and various other math sites (and research papers) around the web include the equations for most of our basic primitives while others are a little more tricky to compute.
+
CAD geometry can have colors specified in a number of ways including directly on that object, in a parent object, and in a lookup tableFor this task, you're going to implement a function that reports the color of an object given a path to that object:
  
This task involves writing a new callback function that takes an rt_db_internal object and calculates the surface area (units are mm^2).  There are numerous examples in our code where we compute surface area for other primitives.  The primitives that do not already have a centroid callback are itemized in following.
+
    int get_color(struct db_i *dbip, const char *path, struct bu_color *rgb);
  
References:
+
You'll need to iteratively consider each object named on the specified path (e.g., "/car/wheel/tire.r/torus") starting with "car" and working your down the path (i.e., 'wheel', 'tire.r', and then 'torus') to 1) see if a color is set on that object and 2) see if that color overrides lower-level colors (i.e., is inherited down the path), and 3) if it's a region object, whether there is a color set in the region table. You'll need to db_lookup() each object on the path to get access to its data.
* http://en.wikipedia.org/wiki/Surface_area
 
* http://mathworld.wolfram.com/
 
* include/raytrace.h: See ft_surf_area callback defined in the rt_functab structure
 
 
 
Code:
 
* src/librt/primitives/[PRIMITIVE]/[PRIMITIVE].c
 
 
 
=== ... surface area function for elliptical hyperboloids (EHY) ===
 
=== ... surface area function for right hyperbolic cylinders (RHC) ===
 
=== ... surface area function for hyperboloids of one sheet (HYP) ===
 
=== ... surface area function for polyhedron with 4 to 8 sides (ARB8) ===
 
=== ... surface area function for N-faced polysolid (ARBN) ===
 
=== ... surface area function for extruded bitmaps (EBM) ===
 
=== ... surface area function for gridded volumes (VOL) ===
 
=== ... surface area function for super ellipsoids (SUPERELL) ===
 
=== ... surface area function for polygonal meshes (NMG) ===
 
=== ... surface area function for triangle meshes (BOT) ===
 
=== ... surface area function for NURBS objects (BREP) ===
 
 
 
== Implement a primitive volume function ==
 
  
BRL-CAD provides more than two dozen types of geometry "primitives" such as ellipsoids, boxes, and cones.  Every primitive is described by a collection of callback functions, for example rt_ell_bbox() returns the bounding box dimensions for an ellipsoid.  Wikipedia, Wolfram Mathworld, and various other math sites (and research papers) around the web include the equations for most of our basic primitives while others are a little more difficult to compute.
+
For this function, you'll want to read up on some of BRL-CAD's basic data structures by looking at headers in the include/rt directory or by reading our [https://brlcad.org/docs/api/ API documentation]. This task may seem complicated if you're not familiar with C/C++ APIs, data structures, or hierarchical paths, so don't be shy [https://brlcad.zulipchat.com asking] questions.
 
 
This task involves writing a new callback function that takes an rt_db_internal object and calculates the volume (units are mm^3). There are numerous examples in our code where we compute volume for other primitives. The primitives that do not already have a volume callback are itemized in following.
 
  
 
References:
 
References:
* http://en.wikipedia.org/wiki/Volume
+
* https://brlcad.org/docs/api/
* http://mathworld.wolfram.com/
 
* include/raytrace.h: See ft_volume callback defined in rt_functab structure
 
  
Code:
+
Code References:
* src/librt/primitives/[PRIMITIVE]/[PRIMITIVE].c
+
* src/libged/display_list.c
 +
* src/libged/color/color.c
 +
* src/librt/prep.c
  
=== ... volume function for right hyperbolic cylinders (RHC) ===
+
&nbsp;
=== ... volume function for elliptical hyperboloids (EHY) ===
+
|}
=== ... volume function for hyperboloids of one sheet (HYP) ===
+
&nbsp;
=== ... volume function for superellipsoids (SUPERELL) ===
 
=== ... volume function for extruded bitmaps (EBM) ===
 
=== ... volume function for gridded volumes (VOL) ===
 
=== ... volume function for triangle meshes (BOT) ===
 
=== ... volume function for solid polygonal meshes (NMG) ===
 
=== ... volume function for extruded sketches (EXTRUDE) ===
 
  
== Implement a primitive centroid function ==
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
  
BRL-CAD provides more than two dozen types of geometry "primitives" such as ellipsoids, boxes, and cones.  Every primitive is described by a collection of callback functions, for example rt_ell_bbox() returns the bounding box dimensions for an ellipsoid.  Wikipedia, Wolfram Mathworld, and various other math sites (and research papers) around the web include the equations for most of our basic primitives while others are a little more tricky to compute.
+
=== Stub in an OpenVDB object ===
  
This task involves writing a new callback function that takes an rt_db_internal object and calculates its centroid (as a point_t 3D point).  There are numerous examples in our code where we compute centroids for other primtiives.  The primitives that do not already have a centroid callback are itemized in following.
+
BRL-CAD has dozens of distinct primitive object types.  For this task, you're going to implement the bare minimum to necessary to create a new object with the "make" command in MGED.
  
References:
+
The best way to achieve this task is by searching for a keyword for another primitive (e.g., 'grep -r -i superell .') and implementing your new object the same way. Start with the 'make' command itself in src/libged/make/make.c and add "vdb" alongside where you find one of the other primitive types (e.g., superell).  To get that to compile, you'll have to add new symbols you've defined into header files (e.g., include/rt/rtgeom.h).  You'll eventually need to implement barebones logic in src/librt/primitives/vdb too.
* http://en.wikipedia.org/wiki/Centroid
 
* http://mathworld.wolfram.com/
 
* include/raytrace.h: See ft_centroid callback defined in the rt_functab structure
 
  
 
Code:
 
Code:
* src/librt/primitives/table.c
+
* include/rt/defines.h <- needs an ID
* src/librt/primitives/[PRIMITIVE]/[PRIMITIVE].c
+
* include/rt/geom.h <- needs an "internal" i.e., in-memory structure
 +
* src/libged/make/make.c <- needs to recognize "vdb" as a valid type
 +
* src/librt/primitives/table.cpp <- needs an entry
 +
* src/librt/primtiives/vdb <- needs a dir
 +
* src/librt/primitives/vdb/vdb.c <- needs _import5/_export5 callbacks, maybe _describe too
  
=== ... centroid function for elliptical hyperboloids (EHY) ===
+
&nbsp;
=== ... centroid function for right hyperbolic cylinders (RHC) ===
+
|}
=== ... centroid function for hyperboloids of one sheet (HYP) ===
+
&nbsp;
=== ... centroid function for polyhedron with 4 to 8 sides (ARB8) ===
 
=== ... centroid function for extruded bitmaps (EBM) ===
 
=== ... centroid function for gridded volumes (VOL) ===
 
=== ... centroid function for N-faced polysolids (ARBN) ===
 
=== ... centroid function for extruded sketches (EXTRUDE) ===
 
=== ... centroid function for superellipsoids (SUPERELL) ===
 
=== ... centroid function for solid polygonal meshes (NMG) ===
 
  
----
+
== Documentation and Training ==
  
= Documentation and Training =
 
----
 
 
''Tasks related to creating/editing documents and helping others learn more about BRL-CAD''
 
''Tasks related to creating/editing documents and helping others learn more about BRL-CAD''
  
== Add missing documentation (for JUST ONE command) ==
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Add missing documentation (for any ONE command) ===
  
 
BRL-CAD is an extensive system with more than 400 commands and more than a million pages of documentation, but there are approximately 120 commands that are entirely undocumented:
 
BRL-CAD is an extensive system with more than 400 commands and more than a million pages of documentation, but there are approximately 120 commands that are entirely undocumented:
Line 268: Line 241:
 
a-d archer asc2g asc2pix bot-bldxf bottest brep_cube brep_simple brickwall btclsh burst bw-a bw-d bwish c-d chan_add clutter contours d-a damdf dauto dauto2 d-bw dconv ddisp d-f dfft d-i dmod double-asc dpeak dsel dsp_add dstat d-u dwin euclid_format euclid_unformat fbgammamod f-d fence fhor f-i g-adrt g-euclid1 g-jack globe g-off i-a i-d i-f ihist imod istat jack-g kurt lowp molecule nmgmodel nmg-sgp off-g pipe pipetest pix2g pix3filter pixcount pixelswap pixembed pixfields pixfieldsep pixflip-fb pixpaste pix-spm pix-yuv plstat pyramid rawbot remapid rlesortmap rletovcr room rtcell rtexample rtfrac rtrad rtsil rtsrv script-tab sketch solshoot sphflake spltest spm-fb ssampview syn tea tea_nmg testfree texturescale torii ttcp tube txyz-pl u-a u-bw u-d u-f umod ustat vcrtorle vegitation wall wdb_example xbmtorle xyz-pl yuv-pix
 
a-d archer asc2g asc2pix bot-bldxf bottest brep_cube brep_simple brickwall btclsh burst bw-a bw-d bwish c-d chan_add clutter contours d-a damdf dauto dauto2 d-bw dconv ddisp d-f dfft d-i dmod double-asc dpeak dsel dsp_add dstat d-u dwin euclid_format euclid_unformat fbgammamod f-d fence fhor f-i g-adrt g-euclid1 g-jack globe g-off i-a i-d i-f ihist imod istat jack-g kurt lowp molecule nmgmodel nmg-sgp off-g pipe pipetest pix2g pix3filter pixcount pixelswap pixembed pixfields pixfieldsep pixflip-fb pixpaste pix-spm pix-yuv plstat pyramid rawbot remapid rlesortmap rletovcr room rtcell rtexample rtfrac rtrad rtsil rtsrv script-tab sketch solshoot sphflake spltest spm-fb ssampview syn tea tea_nmg testfree texturescale torii ttcp tube txyz-pl u-a u-bw u-d u-f umod ustat vcrtorle vegitation wall wdb_example xbmtorle xyz-pl yuv-pix
  
This task involves writing a failed document for '''JUST ONE''' of those commands in the Docbook XML format.  The command documentation should provide a one-sentence description, a detailed paragraph description, explanation of all available command-line options, and one or more examples on how to use the command.
+
This task involves writing basic documentation for '''JUST ONE''' of those commands in the Docbook XML format.  The command documentation should provide a one-sentence description, a detailed paragraph description (200+ words), explanation of '''all''' available command-line options, and one or more examples on how to use the command.  
  
 
Code:
 
Code:
Line 274: Line 247:
 
* doc/docbook/system/man1/en/*.xml
 
* doc/docbook/system/man1/en/*.xml
  
== Write a tutorial on compiling BRL-CAD with XCode on Mac OS X ==
+
&nbsp;
 +
|}
 +
&nbsp;
  
BRL-CAD uses the CMake build system to generate outputs for a variety of platforms.  It will output Makefiles, Microsoft Visual Studio build files, XCode project files, Eclipse build files and more.
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Complete our "Intro to BRL-CAD Modeling" tutorial and extend it ===
  
This task involves generating an XCode project with our build and verifying that it successfully compiles all of BRL-CAD.  Document the process on our wiki as a tutorial.  Include images/screen shots when referring to visual actions within XCode.
+
We've developed two short and simple tutorials for introducing new users to modeling with BRL-CAD.
  
References:
+
This task involves doing one of the tutorials (they take about an hour) and then extending it with a new section or making some other improvement. At the end of the tutorial are several optional advanced "exercise left to the reader", for example. Write a half-page step-by-step for one of the exercises left to the reader.  Include screenshots and images to make it look nice so the reader is not bored.
* http://www.cmake.org/
 
* http://brlcad.org/wiki/
 
  
== Write a tutorial on compiling BRL-CAD with Eclipse on Linux ==
+
Reference:
 +
* Come [https://brlcad.zulipchat.com talk with us] to make sure you get a copy of the latest version.
 +
* https://brlcad.org/w/images/9/90/Intro_to_BRL-CAD.pdf
 +
* https://brlcad.org/w/images/c/cf/Introduction_to_MGED.pdf
 +
* ... there's another new one, but you have to ask for it ...
  
BRL-CAD uses the CMake build system to generate outputs for a variety of platforms.  It will output Makefiles, Microsoft Visual Studio build files, XCode project files, Eclipse build files and more.
+
&nbsp;
 +
|}
 +
&nbsp;
  
This task involves generating an Eclipse project with our build and verifying that it successfully compiles all of BRL-CAD.  Document the process on our wiki as a tutorial.  Include images/screen shots when referring to visual actions within Eclipse.
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
  
References:
+
=== Translate "Contributors Guide To BRL-CAD" To Any Language ===
* http://www.eclipse.org/
 
* http://cmake.org
 
* http://www.cmake.org/Wiki/Eclipse_CDT4_Generator
 
* http://brlcad.org/wiki/
 
  
== Document MGED's 'saveview' command options ==
+
People interested in improving BRL-CAD sometimes find themselves lost in a sea of information. In all, BRL-CAD has more than a million words of documentation across hundreds of manual pages, dozens of tutorials and examples, hundreds of wiki pages, dozens of technical papers, and other resources. There are literally thousands of features and this can sometimes pose problems.
  
BRL-CAD's primary geometry editor (MGED) provides hundreds of commands.  Two of those commands are the savewview and loadview commands that write current view settings out to a text file and read them back in.  The saveview command provides -e -i -l and -o options, but they are not documented.
+
In 2013, a team of contributors got to California and worked on an entire book titled "Contributors Guide To BRL-CAD" in just a few days. This great resource needs to be translated to other languages to attract developers from other lingual backgrounds (who don't read English ) to contribute to BRL-CAD.
  
This task involves writing documentation for those missing options.  Consult the source code to see what they do and add the corresponding sections into our Docbook XML doc just like we do in our other documentation files.  Test compilation to make sure your sytax is correct.
+
This task involves translating the chapters/sections of the "Contributors Guide To BRL-CAD" into a language of your choice such as Mandarin, French, Chinese, Spanish, German, Hindi, Arabic, Russian, etc. Chapters/Sections include
  
References:
+
* Feature Overview
* src/libged/saveview.c
+
* Working with our Code
* doc/docbook/system/mann/en/*.xml
+
* What code to work on
 +
* How to contribute
 +
* .... (Just to name a few )
  
Code:
+
The output of this task can be a pdf, html, doc, odt or any other document file that contains the translated article.Images in the original document (see link in Reference below) should not be changed ! only text should be.
* doc/docbook/system/mann/en/saveview.xml
 
  
== Write "MGED Interface" reference document==
+
Reference:
 +
* http://en.flossmanuals.net/_booki/contributors-guide-to-brl-cad/contributors-guide-to-brl-cad.pdf
  
BRL-CAD's primary geometry editor is called MGED.  MGED's documentation is extensive but incomplete without a concise 1 or 2 page document that details MGED's interface.
+
&nbsp;
 +
|}
 +
&nbsp;
  
This task involves writing an interface reference document that gives a brief descriptive overview of the key bindings, mouse bindings, and primary GUI elements.  The [http://brlcad.org/w/images/8/8c/Shift_Grips_Quick_Reference_Guide.pdf shift grips reference] should be incorporated, albeit much more concisely and organized.
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
  
References:
+
=== Write a "BRL-CAD Commands Quick Reference" document ===
* http://brlcad.org/wiki/Documentation
 
* http://brlcad.org/w/images/c/cf/Introduction_to_MGED.pdf
 
* http://brlcad.org/w/images/8/8c/Shift_Grips_Quick_Reference_Guide.pdf
 
  
== Convert src/conv man pages to valid Docbook  ==
+
There is already a command quick reference for BRL-CAD's MGED geometry editing tool, but there is not a similar document for BRL-CAD's 400+ command-line commands.
  
BRL-CAD is in the process of converting its documentation into Docbook 4.5 format, in order to enable automatic generation of output in different formats (html, pdf, man) from a single sourceThis conversion includes existing UNIX man pages.
+
This task involves writing a quick reference document similar to [http://brlcad.org/w/images/5/52/MGED_Quick_Reference_Card.pdf the MGED quick reference] but for BRL-CAD commandsThe sheet should minimally include the following commands:
  
This task involves using the doclifter tool to perform a rough conversion to Docbook of all man pages in the src/conv subdirectory of the BRL-CAD source tree (about 40 files), then performing whatever manual corrections are needed to the autogenerated xml files to make them valid Docbook (some conversions have already been done and can serve as guides).  The simplest way to confirm the files are successfully converted is to incorporate them into BRL-CAD's build logic for Docbook man pages and view the output using brlman and an html viewer.  It is recommended to use the Emacs editor with the nxml mode in order to more easily identify and fix errors, but this is not a requirement.
+
mged, rt*, *-g, g-*, fb*, *fb, nirt, remrt, rtsrv, asc2g, g2asc, dbupgrade, pix*, *pix, *-*, brlman, benchmark
  
 
References:
 
References:
* Current Docbook man pages: http://brlcad.svn.sourceforge.net/viewvc/brlcad/brlcad/trunk/doc/docbook/system/
+
* http://brlcad.org/wiki/Documentation
* Docbook documentation: http://www.docbook.org/tdg/en/html/docbook.html
+
* http://brlcad.org/w/images/5/52/MGED_Quick_Reference_Card.pdf
* Doclifter conversion tool: http://www.catb.org/~esr/doclifter/
+
* [http://appletree.or.kr/quick_reference_cards/CVS-Subversion-Git/git-cheat-sheet-large.png git example]
* Emacs editor: http://www.gnu.org/software/emacs/emacs.html
+
* [http://www.stdout.org/~winston/latex/latexsheet-0.png latex example]
* nxml Emacs mode: http://www.thaiopensource.com/nxml-mode/
+
* [http://img.docstoccdn.com/thumb/orig/524314.png another example]
 
+
* [http://www.inmensia.com/files/pictures/internal/CheatSheetDrupal4.7.png drupal example]
== Write a "BRL-CAD Commands Quick Reference" document ==
+
* [http://www.phpmagicbook.com/wp-content/uploads/2010/06/php-reference-card.jpg php example]
  
There is already a command quick reference for BRL-CAD's MGED geometry editing tool, but there is not a similar document for BRL-CAD's 400+ command-line commands.
+
&nbsp;
 +
|}
 +
&nbsp;
  
This task involves writing a quick reference document similar to [http://brlcad.org/w/images/5/52/MGED_Quick_Reference_Card.pdf the MGED quick reference] but for BRL-CAD commands.
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 
+
| style="padding: 20px;" |
References:
 
* http://brlcad.org/wiki/Documentation
 
* http://brlcad.org/w/images/5/52/MGED_Quick_Reference_Card.pdf
 
  
== Doxygen cleanup ==
+
=== Doxygen cleanup ===
  
 
BRL-CAD uses Doxygen for most API documentation but the comment blocks are not optimally set up for Doxygen output.
 
BRL-CAD uses Doxygen for most API documentation but the comment blocks are not optimally set up for Doxygen output.
Line 354: Line 333:
 
* http://www.stack.nl/~dimitri/doxygen/
 
* http://www.stack.nl/~dimitri/doxygen/
  
=== ... doxygen cleanup for LIBBU ===
+
&nbsp;
 +
 
 +
{| style="background-color:#efefef; border-style: solid; border-width: 2px;" width="100%"
 +
| style="padding: 10px;" |
 +
==== ... doxygen cleanup for LIBBU ====
  
 
There are approximately 300 documented API function calls in LIBBU.
 
There are approximately 300 documented API function calls in LIBBU.
Line 363: Line 346:
 
* misc/Doxyfile
 
* misc/Doxyfile
  
=== ... doxygen cleanup for LIBBN ===
+
&nbsp;
 +
|}
 +
&nbsp;
  
There are approximately 300 documented API function calls in LIBBN.
+
{| style="background-color:#efefef; border-style: solid; border-width: 2px;" width="100%"
 
+
| style="padding: 10px;" |
Code:
+
==== ... doxygen cleanup for LIBWDB ====
* include/bn.h
 
* include/plot3.h
 
* include/vmath.h
 
* src/libbn
 
* misc/Doxyfile
 
 
 
=== ... doxygen cleanup for LIBWDB ===
 
  
 
There are approximately 100 documented API function calls in LIBWDB.  
 
There are approximately 100 documented API function calls in LIBWDB.  
Line 384: Line 362:
 
* misc/Doxyfile
 
* misc/Doxyfile
  
=== ... doxygen cleanup for LIBRT ===
+
&nbsp;
 +
|}
 +
&nbsp;
 +
 
 +
{| style="background-color:#efefef; border-style: solid; border-width: 2px;" width="100%"
 +
| style="padding: 10px;" |
 +
==== ... doxygen cleanup for LIBRT ====
  
 
There are approximately 1000 documented API function calls in LIBRT.  
 
There are approximately 1000 documented API function calls in LIBRT.  
Line 396: Line 380:
 
* misc/Doxyfile
 
* misc/Doxyfile
  
== Write a "BRL-CAD Ray Tracing Shaders" tutorial ==
+
&nbsp;
 +
|}
 +
&nbsp;
  
BRL-CAD includes numerous shaders that let you specify different optical effects during ray tracing.
+
&nbsp;
 +
|}
 +
&nbsp;
  
This task involves writing a brief tutorial that describes what shaders are and how one specifies them for geometry.  How shaders are specified is already described in detail in the [http://brlcad.org/w/images/c/cf/Introduction_to_MGED.pdf Introduction to MGED] document.
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Add images to our wiki page on Volumetric objects ===
  
Code:
+
BRL-CAD provides a couple dozen distinct primitives.  Each primitive is defined by a set of parameters.  Several of the more complex primitives have a wiki page describing them in more detail with an example on how to create them.
* src/liboptical/sh_*.c (for available shader names and corresponding options)
+
 
 +
This task involves adding images to our page for the VOL primitiveYou'll need to first complete the tutorial and save images for each step.  Add the images to the wiki page.
  
 
References:
 
References:
* http://brlcad.org/w/images/2/2c/Optical_Shaders.pdf
+
* http://brlcad.org/wiki/VOL
* http://brlcad.org/w/images/c/cf/Introduction_to_MGED.pdf
+
* http://brlcad.org/wiki/DSP
 +
* http://brlcad.org/wiki/Sketch
 +
* http://brlcad.org/wiki/EBM
 +
 
 +
&nbsp;
 +
|}
 +
&nbsp;
 +
 
 +
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Fix Image Formatting in BRL-CAD's DocBook Documentation (any ONE large document or 4 smaller documents) ===
 +
 
 +
The majority of BRL-CAD's documentation is defined as DocBook files, from which other formats (HTML, PDF, man page, etc.) can be generated.  PDF files present a particular challenge, and have some very specific requirements to achieve "good" formatting.
 +
 
 +
BRL-CAD's DocBook files need to uniformly use a style of image inclusion that is aware of what "role" the image is supposed to serve.  A "basic" image inclusion example looks like this:
 +
 
 +
  <mediaobject>
 +
    <imageobject>
 +
      <imagedata align="center" fileref="../../lessons/en/images/img.png" format="PNG"/>
 +
    </imageobject>
 +
    <nowiki><caption></nowiki>
 +
      <para>
 +
        Caption goes here.
 +
      </para>
 +
    </caption>
 +
  </mediaobject>
  
----
+
This task involves switching image inclusions that use the above style to something like the following:
  
= Outreach and Research =
+
  <mediaobject>
----
+
    <imageobject role="html">
''Tasks related to community management, outreach/marketing, studying problems, and recommending solutions''
+
      <imagedata align="center" fileref="../../books/en/images/img.png" format="PNG"/>
 +
    </imageobject>
 +
    <imageobject role="fo">
 +
      <imagedata align="center" fileref="../../books/en/images/img.png" format="PNG"/>
 +
    </imageobject>
 +
    <nowiki><caption></nowiki>
 +
      <para>
 +
        Caption goes here.
 +
      </para>
 +
    </caption>
 +
</mediaobject>
 +
 +
The "role" flag to imageobject provides the opportunity to specify different image formatting options when the output is HTML (role="html") or PDF (role="fo").
  
== Write solicitation for new website designer ==
+
The captions should be preserved as above on mediaobjects that have them, but mediaobjects without a caption should also be converted and there is no need to add a caption in such cases.
  
The BRL-CAD website is in need of a design overhaul.
+
Any patch that makes changes to the DocBook sources should result in a successful "make doc" build test.  This won't generate PDF documents, but it will validate the XML files and produce HTML - remember that introducing breakage means the patch won't be accepted.
  
This task involves writing up a brief article soliciting new contributor(s) to work on designing a new websiteThe article needs to be detailed and specific to our particular website requirements (Drupal+Mediawiki+CSS) to ensure the contributor can design the appropriate stylesheet(s), updated graphics, and new layout.
+
Remember, the tasks are simply to do the above conversion for all images in the file or files, not to introduce PDF specific formattingFormatting fixes will be needed, but they are very much "case by case" and will take both additional time and a working Apache FOP installation, as well as knowledge of how to enable PDF generation.  If all image inclusions have been converted successfully and a student is interested in actually fixing the formatting, please discuss it with us on IRC or the mailing list.
  
 
References:
 
References:
* http://brlcad.org
+
* doc/docbook/books/en/BRL-CAD_Tutorial_Series-VolumeIII.xml
 +
 
 +
Code:
 +
* doc/docbook
 +
 
 +
&nbsp;
 +
|}
 +
&nbsp;
 +
 
 +
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Find 5 bugs in OGV ===
 +
 
 +
Online Geometry Viewer is a web based application with which you can see 3D .g models in browser without the use of any plugins. Your task will be to deploy OGV locally and find 5 bugs or errors in it.
 +
 
 +
Links:
 +
https://github.com/BRL-CAD/OGV-meteor/
  
== Model new BRL-CAD Logo using BRL-CAD ==
+
&nbsp;
 +
|}
 +
&nbsp;
  
The winner of the recent BRL-CAD Logo contest is a clean depiction of two interlocked components. Modeling the new Logo in BRL-CAD without using NURBS would require some careful arrangement, but would provide an attractive three dimensional rendering.
+
==Outreach and Research ==
 +
''Tasks related to community management, outreach/marketing, studying problems, and recommending solutions''
  
The output of this task would be a .asc file of BRL-CAD geometry (converted via g2asc) for inclusion in the db/ example directory.  Optimally, the two segments would overlap at the join, but this is your opportunity as an artist and 3D magician to shine with your interpretation.
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Profile NURBS prep performance ===
  
References:
+
BRL-CAD implements support for rendering of NURBS representation geometry.  If you import a solid 3DM or STEP format model into BRL-CAD, it will import as BREP/NURBS geometry. Opening that geometry in BRL-CAD's MGED editor will tell you what objects are available and our 'rt' tool will raytrace it. When geometry is ray traced, it first goes through a "prep" phase and then it starts shooting rays. Our prep phase is entirely unoptimized so we'd like to know where all the time is presently being spent during prep..
* http://brlcad.org/images/angelov_256.png
+
 
* http://brlcad.org/d/node/92
+
This task involves importing some NURBS geometry into BRL-CAD and ray tracing that geometry with a profiler watching our prep performance.  Any profiler will do, including gprof, but a performance monitor like oprofile or the Mac "Instruments" application (or Shark) are preferred.
* Introduction to MGED at http://brlcad.org/wiki/Documentation
 
  
== Write BRL-CAD News article on .deb/.rpm builds ==
+
Learning how to use a profiler is beyond the scope of this task, so it make take you considerably longer to provide us with useful information if you've never run a profiler before.
  
BRL-CAD has a new maintainer, Jordi Sayol, for managing .deb and .rpm buildsInterview the developer, obtain details on how the releases are produced, what platforms are supported, etc, and write up an article for our Community Publication Portal (CPP)
+
To capture prep performance, you will need to import some fairly complex geometryYou should be able to search google with "filetype:3dm" or "filetype:step" or find something on grabcad.com to import
  
The output of this task is an article added to our CPP wiki page in a final production-quality review state.
+
Running "tops" within mged will tell you what geometry is available for rendering.
  
References:
+
Running "rt -o file.png -s32" on the system command line (not inside mged) should minimize the ray overhead or you can specifically isolate the prep phase we care about.  Prep is the time between when rt is run where it opens a window until the first pixels are fired and pixels start filling in.
* http://brlcad.org/wiki/Community_Publication_Portal
 
  
== Write a BRL-CAD model showcase article ==
+
&nbsp;
 +
|}
 +
&nbsp;
  
BRL-CAD has several geometry models developed by community members that showcase the power and applicability of BRL-CAD to various domains.  For this task, you'd be expected to interview one or more individuals to obtain information and pictures about their project, write up a descriptive overview of their model, the goals of the project, and any interesting ancillary information that may be relevant.  There are presently several candidate topics listed in our Community Publication Portal (CPP).
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Continue investigating GMP integration ===
  
The output of this task is an article added to our CPP wiki page in a final production-quality review state.
+
BRL-CAD uses a fastf_t typedef for most all math operations that is usually a "double" floating point type. We would like to provide the option for resorting to exact arithmetic if possible by merely redefining fastf_t to a C++ type sufficiently overloaded to behave the same. You should be proficient with C++ operator overloading to take this work on.  This task is a continuation of a prior GCI task (read it in full!):
  
References:
+
http://www.google-melange.com/gci/task/view/google/gci2012/7946218
* http://brlcad.org/wiki/Community_Publication_Portal
 
  
== Design a "Commercial CAD Comparison" diagram ==
+
This task involves testing compilation with a C++ class with overloaded operators such that vmath macro calls still work as well as a sampling of LIBBN API function calls without major changes to the original code. A perfect example case study would be creating the class then testing whether bn_dist_pt3_pt3() and bn_mat_determinant() compute correctly for values that cannot be exactly represented with floating point arithmetic.
  
New users frequently ask how BRL-CAD compares to other major commercial CAD systems such as CATIA, Unigraphics/NX, Pro/ENGINEER, Solidworks, and AutoCADBRL-CAD has many of the same features and it would be very useful to visualize the feature overlap graphically with a diagram.
+
Building on the previous GCI task work, take it to the next step.  Try setting a vector to 1/3, 1/3, 1/3 and 0.1, 0.1, 0.1 and get proper values to printChange the V3ARGS() macro if needed.  If that all works, try to get bn_dist_pt3_pt3() to work.  Report and discuss your progress.
  
This task involves identifying core significant features of relevance and describing BRL-CAD along with the various major CAD vendors.  The diagram should fit on one page.
+
&nbsp;
 +
|}
 +
&nbsp;
  
References:
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
* http://brlcad.org/Industry_Diagram.png
+
| style="padding: 20px;" |
* Example feature comparisons (although not a diagram): http://en.wikipedia.org/wiki/Comparison_of_3D_computer_graphics_software
+
=== Upgrade OpenNURBS, report issues ===
* Additional feature comparisons (also not a diagram): http://en.wikipedia.org/wiki/Comparison_of_CAD_editors_for_CAE
 
  
== Investigate performance of setting thread affinity ==
+
BRL-CAD uses a customized OpenNURBS library for advanced geometry but it's out of date.  For this task, you're going to download the latest OpenNURBS code and upgrade the sources we bundle.  The easiest way is probably to move src/other/openNURBS to src/other/openNURBS.backup, and then put the latest OpenNURBS release into src/other/openNURBS.
  
BRL-CAD's raytrace library (LIBRT) is pervasively multithreaded using routines defined in our basic utility library (LIBBU) for detecting an using multiple CPUs/cores/threads.
+
Once that's done, you'll need to add the src/other/openNURBS.backup/CMakeLists.txt file and make sure the list of files it has matches the files in src/other/openNURBS.  Last but not least, re-run cmake and make sure it compiles.  You may need to consult the newer openNURBS makefile to see if there are other edits needed in the CMakeLists.txt file.
  
This task involves making minor modifications to the LIBBU parallel interface using sched_setaffinity and/or pthread_attr_setaffinity_np (or similar affinity mechanism depending on the platform) and then evaluating the performance impact using our BRL-CAD Benchmark suite ('benchmark' command).
+
Save output from any commands you run because you'll probably encounter an error, and that's okay.  Just submit logs of all output so we can figure out next steps.
 +
 
 +
References:
 +
* https://github.com/mcneel/opennurbs
  
 
Code:
 
Code:
* src/libbu/parallel.c
+
* src/other/openNURBS <- replace existing with latest openNURBS from github
* src/libbu/semaphore.c
 
  
== Determine why solids.sh fails on 64-bit ==
+
&nbsp;
 +
|}
 +
&nbsp;
  
BRL-CAD has a regression test script called solids.sh that creates a bunch of primitives, renders an image of those primitives, and then compares that image to a reference image.  On (most?) 64-bit platforms, the test is off by several RGB values for exactly 3 pixels.
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Design a T-Shirt for BRL-CAD ===
  
This task involves figuring out why, exactly, this is occurring. It may be helpful to compare intermediate computation results from a 32-bit environment to see where the computations diverge, however slightly. Ultimately, the goal is to identify the cause and a recommended course of action to fix the divergence problem.
+
This task involves designing a T-Shirt for BRL-CAD. Use your designing skills to design a T-Shirt for BRL-CAD. You can use the current BRL-CAD logo, or you may tweak it. Be creative while designing this T-Shirt. It would be good if the design has some special meaning.
  
Code:
+
Logo References
* regress/solids.sh
+
* [https://brlcad.org/img/logo_color.png BRL-CAD Logo]
 +
 
 +
&nbsp;
 +
|}
 +
&nbsp;
 +
 
 +
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Design a coffee mug for BRL-CAD ===
  
== Investigate permuted vertex lists from g-iges + iges-g ==
+
This task involves designing a coffee mug for BRL-CAD. Make it look good or at least interesting, and make it in BRL-CAD. Look over some coffee mug designs before starting to work on this.  Verify that your mug is valid geometry by running the "rtcheck" command.
  
BRL-CAD has a geometry exporter and importer for the International Graphics Exchange Standard (IGES) file format. If you run our g-iges exporter on some geometry, then run iges-g on that same geometry to import it back to BRL-CAD format, the geometry will have permuted vertex lists.  Particularly for geometry already in polygonal format, such as our NMG or BoT geometry, this conversion should result in identical geometry but presently does not.
+
Logo References
 +
* [https://brlcad.org/img/logo_color.png BRL-CAD Logo]
  
This task involves investigating why this occurs, reporting (in detail) why it occurs, and if obvious, making a recommendation on how to fix the problem.
+
&nbsp;
 +
|}
 +
&nbsp;
  
Code:
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
* src/conv/iges
+
| style="padding: 20px;" |
 +
=== Design BRL-CAD sticker ===
  
== Investigate GMP integration ==
+
This task involves designing a BRL-CAD sticker. The design should be simple and sleek. The concept of sticker should be clear and also it should be creatively presented. Get inspired from some sticker designs but choose your own imagination while designing the sticker. There is no bound for shape of sticker, it can be rectangular, circular or even irregular. The only thing that matters is that it should look good.
  
BRL-CAD uses a fastf_t typedef for most all math operations that is usually a "double" floating point type.  We would like to provide the option for resorting to exact arithmetic if possible by merely redefining fastf_t to a C++ type sufficiently overloaded to behave the same.
+
Logo References
 +
* [https://brlcad.org/img/logo_color.png BRL-CAD Logo]
  
This task would involve implementing a C++ class with overloaded operators such that vmath macro calls still work as well as a sampling of LIBBN API function calls without major changes to the original code.  A perfect example case study would be creating the class then testing whether bn_dist_pt3_pt3() and bn_mat_determinant() compute correctly for values that cannot be exactly represented with floating point arithmetic.
+
&nbsp;
 +
|}
 +
&nbsp;
  
Code:
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
* include/vmath.h
+
| style="padding: 20px;" |
* include/bn.h
+
=== Design a wallpaper / desktop image for BRL-CAD ===
  
References:
+
This task involves designing a desktop background for BRL-CAD enthusiasts.  The main idea of your wallpaper should be to showcase one or more features of BRL-CAD.  Be intentional and able to defend/describe your choice of color, layout, and other aspects of the wallpaper design.
* http://gmplib.org/
+
 +
Try to make sure the wallpaper works across a broad selection of screen resolutions.
  
== Investigate the status of our command spreadsheet ==
+
Search the web for wallpapers inspiration such as:
 +
* http://www.smashingmagazine.com/tag/wallpapers/
  
We have a spreadsheet filled with information about all of BRL-CAD's 400+ commands including details about what command line options, inputs, and outputs are supported.  The spreadsheet is not complete, however, and hasn't been reviewed in a couple years.
+
Logo References
 +
* [https://brlcad.org/img/logo_color.png BRL-CAD Logo]
  
This task involves comprehensively going over the 400+ rows of the spreadsheet to systematically verify that the information is complete and correct, and to fill in missing information where needed.  This task requires strong familiarity with the UNIX command line, manual pages, and how to pipe input to/from applications in a variety of formats.
+
&nbsp;
 +
|}
 +
&nbsp;
  
Code:
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
* src/ .. everywhere
+
| style="padding: 20px;" |
 +
=== Model a Lightcycle in BRL-CAD using CSG ===
  
References:
+
The movie Tron is an iconic computer graphics film that used CSG primitives for a majority of the movie's 3D virtual world.  The film is famous for "lightcycle" vehicles that were allegedly modeled using 57 primitives and/or Boolean operations.  For this task, see if you can recreate the masterpiece in BRL-CAD.
* Existing spreadsheet available on request
+
 +
See this lightcycle discussion thread
 +
* http://www.tron-sector.com/forums/default.aspx?a=top&id=336281
  
----
+
&nbsp;
 +
|}
 +
&nbsp;
  
= Quality Assurance =
+
== Quality Assurance ==
----
 
 
''Tasks related to testing and ensuring code is of high quality''
 
''Tasks related to testing and ensuring code is of high quality''
  
== Fix single-precision floating point crash ==
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Fix single-precision floating point crash ===
  
 
By default, all of BRL-CAD compiles using double-precision floating point arithmetic.  We provide a simple typedef, however, that converts almost the entire system over to single-precision floating point.  This compilation mode was recently cleaned up and tested, but a bug was found.  The problem is reproduced very simply by compiling in single precision mode and running our "rt" ray tracer tool.
 
By default, all of BRL-CAD compiles using double-precision floating point arithmetic.  We provide a simple typedef, however, that converts almost the entire system over to single-precision floating point.  This compilation mode was recently cleaned up and tested, but a bug was found.  The problem is reproduced very simply by compiling in single precision mode and running our "rt" ray tracer tool.
Line 555: Line 638:
 
* src/liboptical/sh_light.c
 
* src/liboptical/sh_light.c
  
== Develop an N-Manifold Geometry (NMG) testing framework==
+
&nbsp;
 +
|}
 +
&nbsp;
 +
 
 +
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Fix closedb ===
  
BRL-CAD implements polygonal facetted geometry as "NMG" geometry, which is then used for converting from an implicit constructive solid geometry (CSG) representation to a mesh formatThis is a huge portion of BRL-CAD's core libraries that is used by dozens of tools and commands so there is a need for improved robustness.
+
BRL-CAD geometry editor application (mged) has several hundred commands including two very simple commands for opening and closing a geometry database fileWhile the user rarely ever needs to close the file, as all changes are always immediately saved, it can be of use to scripting applications.  However, at some point in the recent past, the ''closedb'' command was horked.  It's undoubtedly something very simple but we haven't bothered to look due to other priorities.  You can fix it.  If you run these simple steps within graphical mged, you should see how commands stop working after calling closedb:
  
This task involves custom scripting or using a testing framework (such as googletest) that attempts to convert all of BRL-CAD's provided sample geometry into NMG format. There are more than 500 functions in the NMG code, so this task only exercises the NMG code indirectly through one of BRL-CAD's numerous geometry exporters such as g-nmg or g-dxf.  The testing should report which objects do not successfully convert and percentage conversion success.
+
  mged> opendb test.g y
 +
  mged> make sph sph
 +
  mged> l sph
 +
  mged> closedb
 +
  mged> make sph sph
 +
  mged> opendb test.g
 +
  mged> l sph
 +
  mged> exit
  
Files:
+
Provide a patch that fixes the bug or tell us which SVN revision introduced the bug. Make sure you can reproduce the bug before claiming this task, which presumes you know how to download/install BRL-CAD from a source distribution.
* db/*.g
 
* src/conv/g-nmg
 
  
References:
+
Code:
* http://en.wikipedia.org/wiki/Topological_manifold
+
* src/mged/mged.c
* http://en.wikipedia.org/wiki/Constructive_solid_geometry
+
 
* http://code.google.com/p/googletest/
+
&nbsp;
 +
|}
 +
&nbsp;
  
== Create comprehensive utility library (LIBBU) API unit tests ==
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Create a utility library (LIBBU) API unit test ===
  
 
There are more than 300 library functions in our core LIBBU library.  As a core library used by nearly every one of BRL-CAD's tools, testing those functions for correct behavior is important.
 
There are more than 300 library functions in our core LIBBU library.  As a core library used by nearly every one of BRL-CAD's tools, testing those functions for correct behavior is important.
  
This task involves implementing a testing framework for LIBBU that exercises every single one of the public API C function calls and reports whether tests pass successfully or not.
+
This task involves implementing new unit tests for any of LIBBU's source files that do not already have a unit test defined.  The test should run all of the public functions and be hooked into our build system.  We have lots of existing unit tests to follow as examples.
 +
 
 +
References:
 +
* include/bu.h
 +
* src/libbu/*.c
 +
* src/libbu/tests/*.c
  
 
Code:
 
Code:
* include/bu.h
+
* src/libbu/tests/[TEST].c
* src/libbu
+
* src/libbu/tests/CMakeLists.txt
 +
 
 +
&nbsp;
 +
|}
 +
&nbsp;
  
References:
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
* http://code.google.com/p/googletest/
+
| style="padding: 20px;" |
  
== Create comprehensive numerics library (LIBBN) API unit tests ==
+
=== Create Numerics library (LIBBN) API unit tests ===
  
 
There are more than 300 library functions in our core LIBBN library.  As a core library used by nearly every one of BRL-CAD's tools, testing those functions for correct behavior is important.
 
There are more than 300 library functions in our core LIBBN library.  As a core library used by nearly every one of BRL-CAD's tools, testing those functions for correct behavior is important.
  
This task involves implementing a testing framework for LIBBN that exercises every single one of the public API C function calls and reports whether tests pass successfully or not.
+
This task involves implementing new unit tests for any of LIBBN's source files that do not already have a unit test defined.  The test should run all of the public functions and be hooked into our build system.  We have lots of existing unit tests to follow as examples.
  
Code:
+
References:
 
* include/bn.h
 
* include/bn.h
 
* include/plot3.h
 
* include/plot3.h
 
* include/vmath.h
 
* include/vmath.h
* src/libbn
+
* src/libbn/*.c
 +
* src/libbn/tests/*.c <-- check this directory for examples
 +
* src/libbu/tests/*.c <-- Note: Also check this too for more examples.
  
References:
+
Code:
* http://code.google.com/p/googletest/
+
* src/libbn/tests/[TEST].c
 +
* src/libbn/tests/CMakeLists.txt
 +
 
 +
<b> Note </b>
 +
A valid task will constitute writing a basic test for each function in the following libbn/ files.
 +
 
 +
&nbsp;
 +
 
 +
{| style="background-color:#efefef; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
==== ... unit tests for LIBBN anim.c ====
 +
&nbsp;
 +
|}
 +
&nbsp;
 +
 
 +
{| style="background-color:#efefef; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
==== ... unit tests for LIBBN axis.c ====
 +
&nbsp;
 +
|}
 +
&nbsp;
  
== Create a comprehensive unit test for bn_dist_pt3_pt3() ==
+
{| style="background-color:#efefef; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
==== ... unit tests for LIBBN qmath.c ====
 +
&nbsp;
 +
|}
 +
&nbsp;
  
There are more than 300 library functions in our LIBBN numerics library. Creating a comprehensive unit test involves exhaustively exploring all possible inputs to the function, testing them for proper behavior, and characterizing the output in a PASS/FAIL fashion.
+
{| style="background-color:#efefef; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
==== ... unit tests for LIBBN rand.c ====
 +
&nbsp;
 +
|}
 +
&nbsp;
  
Unlike the other testing framework tasks, the goal of this task is comprehensiveness. The task must cover all possible inputs including NULL, -inf, +inf, NaN, real numbers, and other values in most if not all possible combinations.
+
{| style="background-color:#efefef; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
==== ... unit tests for LIBBN vector.c ====
 +
&nbsp;
 +
|}
 +
&nbsp;
  
Code:
+
&nbsp;
* include/bn.h
+
|}
* src/libbn
+
&nbsp;
  
References:
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
* http://code.google.com/p/googletest/
+
| style="padding: 20px;" |
  
== Find, reproduce, confirm, and report any bug in Archer ==
+
=== Find, reliably reproduce, and report any bug in Archer ===
  
Archer is our new modeling interface and a soon-to-be replacement for our long-standing MGED geometry editor.  It undoubtedly has bugs.  It's your job to find them, but do so in a manner that is so obvious that one of the other devs will be able to instantly reproduce the bug given your instructions.  Crashing bugs are best, but may require learning how to use the tool with minimal documentation.
+
Archer is our new modeling interface and a soon to merge with our long-standing MGED geometry editor.  It undoubtedly has bugs.  It's your job to find one, but do so in a manner that is so obvious that one of the other devs will be able to instantly reproduce the bug given your specific instructions.  Find a way to make archer crash, become unresponsive, or otherwise behave incorrectly.  You will have to explore the tool with minimal documentation.
  
This task involves filing a bug report with verifiable and reproducible steps that clearly demonstrate the bug.  It can't be a bug already reported or otherwise documented.
+
This task involves filing a bug report with verifiable and reproducible steps that clearly demonstrate the bug.  It can't be a bug already reported or otherwise documented nor can it be merely behavior you don't like.
  
 
References:
 
References:
Line 623: Line 767:
 
* http://sourceforge.net/tracker/?atid=640802&group_id=105292&func=browse
 
* http://sourceforge.net/tracker/?atid=640802&group_id=105292&func=browse
  
----
+
&nbsp;
 +
|}
 +
&nbsp;
 +
 
 +
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Reproduce any 10 unconfirmed open bug reports ===
 +
 
 +
BRL-CAD presently has approximately 75 open bug reports of which 50 are unassigned.  Read the comments and status to see if the bug has been confirmed/reproduced. 
 +
 
 +
This task involves going through those reports and REPRODUCE at least 10 of the ones that have not been confirmed.  When you can reproduce the issue being reported, you'll comment on the thread to state as much and attach any data you used to reproduce the crash.
 +
 
 +
References:
 +
* https://sourceforge.net/tracker/?limit=100&func=&group_id=105292&atid=640802&assignee=100&status=1&submit=Filter
 +
 
 +
&nbsp;
 +
|}
 +
&nbsp;
  
= User Interface =
+
== User Interface ==
----
 
 
''Tasks related to user experience research or user interface design and interaction''
 
''Tasks related to user experience research or user interface design and interaction''
  
== Design an MGED command spreadsheet ==
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Create an ISST screenshot or animation ===
  
BRL-CAD's primary solid geometry modeling application is called MGED. MGED contains a comprehensive set of more than 700 commands for manipulating, viewing, and inspecting geometry. There is a need to more effectively manage those commands, characterize them all, and get a "big picture" of the command landscape so that usability may be addressed.
+
Everyone loves to see screenshots and animations of software in action. We use both in our marketing and outreach. See some of the examples below that we already have.
  
This task involves designing a spreadsheet that will be used to characterize all of MGED's commands.
+
Create an awesome screenshot and/or animation of our 'isst' tool in action. It's an interactive geometry viewer interface.  It should be graphically interesting and give some sense of capability.  You should import a visually complex and interesting model with LOTS of polygons and detail.  Note you may have to go through some or the MGED tutorials (see Docs on our website).
  
 
References:
 
References:
* An existing spreadsheet already being used for BRL-CAD (i.e., non-MGED) commands is available.
+
* https://brlcad.org/gallery/index.php?/category/12
  
== Create prototype 2D CAD drawing(s) ==
+
&nbsp;
 +
|}
 +
&nbsp;
  
BRL-CAD provides limited services for drafting features including the production of 2D CAD drawings (blueprints).
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
  
This task involves designing a 2D CAD drawing prototype that effectively captures a set of design requirements and follows industry conventions.  Basically, this requires identifying one or more style(s) of drawings that should be supported along with critical elements to be included on each drawing.
+
=== Categorize commands into a spreadsheet ===
 
 
References:
 
* http://brlcad.org/design/drafting
 
* http://en.wikipedia.org/wiki/ISO_128
 
* http://en.wikipedia.org/wiki/ASME_Y14.41-2003
 
* http://en.wikipedia.org/wiki/Geometric_Dimensioning_and_Tolerancing
 
* http://www.ptc.com/WCMS/files/45691/en/4307_FoundationXE_DS.pdf
 
 
== Create prototype CAD GUI layout diagram ==
 
  
BRL-CAD's usability is notoriously complex and "expert friendly".  MGED and Archer are the main geometry editors, with drastically different user interfaces.
+
BRL-CAD is a suite of more than 400 commands, processing tools, image tools, geometry converters, and more.  MGED also has a command-line with hundreds of commands too.  Help us reorganize one of those command sets.
  
This task involves evaluating the features provided by MGED and Archer, then designing a new GUI layout that encompasses their features while improving usabilityRationale for design decisions and layout should be provided.
+
This task involves creating a spreadsheet that lists all commands and groups them together into a finite set of categories or labelsThis spreadsheet will help us identify places where commands can be consolidated, commands we might want to consider removing, common groupings for documentation, etc.
  
References:
+
&nbsp;
* http://brlcad.org/design/gui
+
|}
 +
&nbsp;
  
== Reorganize MGED menu ==  
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
  
BRL-CAD's main graphical user interface, MGED, is heavily menu-driven but not exceptionally well organized.  This task involves performing an exhaustive review of MGED's various menus, including temporary menus when in a given editing state, reorganizing them for logical groupings, and rewording them for clarity.  It's necessary to learn the basics of the MGED interface in order to understand what the various options do.
+
===  Design a Cover Photo for Facebook (and other social media) ===
  
For this task, you'll provide a description of the existing menus and mapping to a new organization including basic rationale behind any new groupings or rewording.  
+
BRL-CAD website and marketing materials are constantly undergoing change.  Effective marketing requires well designed and attractive imagery. Imagery ideally should showcase some feature of BRL-CAD, some highlight, something visually interesting and compelling.
  
 
References:
 
References:
* Introduction to MGED at http://brlcad.org/wiki/Documentation
+
* https://www.facebook.com/brlcad
  
== Categorize all of BRL-CAD's commands into a spreadsheet ==
+
&nbsp;
 +
|}
 +
&nbsp;
  
BRL-CAD is a suite of more than 400 processing tools, image tools, geometry converters, and more.  There is an existing spreadsheet that characterizes all of the available commands in terms of inputs, outputs, and options, but there is insufficient characterization of BRL-CAD's commands as to how they logically group and work together.
+
{| style="background-color:#fefefe; border-style: solid; border-width: 4px;" width="100%"
 +
| style="padding: 20px;" |
 +
=== Create a video for BRL-CAD ===
  
This task involves building up a spreadsheet that lists all of our commands, describing a finite set of command categories, and characterizing all commands into those categories while filling in the spreadsheet with details for each command.
+
Watching someone else use software is incredibly helpful to some.  Create a screen-cast video for BRL-CAD that showcases some  feature, goes over steps involved in creating some model, or shows how to accomplish some other task.
  
References:
+
You'll need to install BRL-CAD on your computer and use it in the video.  Create or import some model and make a recording.
* A spreadsheet template will be provided.
 
  
== Template example title ==
+
&nbsp;
 +
|}
 +
&nbsp;
  
This is a template for mentors adding new ideas.  Brief background information not specific to the task is listed first.  It's succinct.
+
= When You're Done =
  
This task involves ... the rest goes hereRemember, less than two hours expected for average or random contributor to do the work after reading this descriptionThe resulting task should be directly measurable without subjective interpretationTell them exactly what they need to do.  Be specific.
+
For non-code, just send us your file(s)For code changes, you will be expected to [[Patches|provide a patch file]]Make sure you ''read'' your patch file before submitting itMake sure your patch file will apply cleanly to an unmodified checkout of BRL-CAD:
  
References:
+
svn co https://brlcad.svn.sourceforge.net/svnroot/brlcad/brlcad/trunk brlcad.edit
* optionally list any url's that provide relevant background information
+
cd brlcad.edit
 
+
# make changes
Code:
+
svn diff > ~/my.patch
* list any files you know they will need to read/edit
+
# read ~/my.patch file with text editor
 +
cd ..
 +
svn co https://brlcad.svn.sourceforge.net/svnroot/brlcad/brlcad/trunk brlcad.fresh
 +
cd brlcad.fresh
 +
patch -p0 < ~/my.patch
 +
# submit your patch file to our patches tracker
 +
&nbsp;

Latest revision as of 11:17, 30 October 2020

Below are tasks that are a great starting point for anyone interested in contributing to BRL-CAD. Most tasks can be completed in just a couple hours! No prior experience with BRL-CAD is required.

Some tasks may take longer if you aren't set up or haven't done that type before, but all they all require about the same amount of experienced effort. Each task has a description, references, and list of files you'll probably need. Can we make it any easier? Let us know.

Get Set Up[edit]

We suggest you compile BRL-CAD yourself or, if you have trouble with that, there's a virtual image with everything preconfigured, ready to go:

  1. Download our BRL-CAD Virtual Machine (VM) disk image.
  2. Install VirtualBox.
  3. Import the disk image, start the VM, and log in (password is "Brlcad!" without quotes).
  4. Run "svn up brlcad-svn-trunk" and compile.

Pick a Task[edit]

Once set up, select any task that sounds interesting, read the references, and talk with us for help. Don't worry if some words are confusing. You got this. All tasks can be completed by anyone but are grouped into the following five interest categories:

  • Code (programming)
  • Documentation and Training (technical writing)
  • Outreach and Research (graphics, marketing)
  • Quality Assurance (testing)
  • User Interface (usability, design)

Contents


Code[edit]

Tasks related to writing or refactoring code

See the When You're Done section above for details on submitting your changes.


Close MGED only when both windows are closed[edit]

BRL-CAD has an interactive geometry editor called MGED. It's often the starting point for beginners and allows creation and manipulation of models using commands. When mged is run, it creates 2 windows: a text console for commands and an interactive graphics window. Currently, if you close the graphics window, it quits the application.

This task involves change behavior so that MGED exits only after closing both windows. Closing just the graphics window or text console should not quit MGED.

Code:

  • src/mged/mged.c
  • src/tclscripts/mged/openw.tcl
  • src/tclscripts/mged/bindings.tcl

 

 

Implement a primitive centroid function[edit]

BRL-CAD provides more than two dozen types of geometry "primitives" such as ellipsoids, boxes, and cones. Every primitive is described by a collection of callback functions, for example rt_ell_bbox() returns the bounding box dimensions for an ellipsoid. Wikipedia, Wolfram Mathworld, and various other math sites (and research papers) around the web include the equations for most of our basic primitives while others are more tricky to compute.

This task involves writing a new callback function that takes an rt_db_internal object and calculates its centroid (as a point_t 3D point). There are numerous examples in our code where we compute centroids for other primitives. The primitives that do not already have a centroid callback are itemized in following.

References:

Code:

  • src/librt/primitives/table.c
  • src/librt/primitives/[PRIMITIVE]/[PRIMITIVE].c

 

 

Implement a primitive curvature function[edit]

BRL-CAD provides more than two dozen types of geometry "primitives" such as ellipsoids, boxes, and cones each described by a collection of callback functions, for example rt_sph_bbox() returns the bounding box dimensions for a sphere. Wikipedia, Wolfram Mathworld, and various other math sites (and research papers) around the web include the equations for most of our basic primitives while others are a little more tricky to compute.

This task involves writing the callback function rt_xxx_curve() that computes the curvature at a given point on the surface of a primitive such as;

  • superell
  • cline
  • extrude
  • grip
  • metaball
  • hrt.

There are numerous examples in our code where we compute the curvature for other primitives like the ellipsoid, sphere, elliptical parabola, etc.

References:

Code:

  • src/librt/primitives/table.c
  • src/librt/primitives/[PRIMITIVE]/[PRIMITIVE].c

 

 

Implement a primitive UV-mapping callback[edit]

BRL-CAD provides more than two dozen types of geometry "primitives" such as ellipsoids, boxes, and cones. Every primitive is described by a collection of callback functions, for example rt_ell_bbox() returns the bounding box dimensions for an ellipsoid. One of those functions describes a UV mapping of the object's surface, which is used for things like texture and bump mapping. An example of this is rt_ell_uv() in the src/librt/primitives/ell/ell.c source file for an ellipsoid. Several of our more complex primitive types (such as BoT, NMG, and BREP/NURBS) do not presently implement a UV-mapping function leading to unexpected runtime behavior.

This task involves implementing a UV-mapping callback for any of the primitives that do not already have a functional UV-callback defined. Note that this is an advanced task that might take you more than a couple hours if you don't have solid coding skills, but it's ultimately just a few lines of code. See other primitives that already implement a UV-mapping callback for reference.

References:

Code:

  • src/librt/primitives/extrude/extrude.c
  • src/librt/primitives/table.c
  • include/rtgeom.h

 

 

Debug and fix a bug converting cylinders[edit]

BRL-CAD has many 3D object types, one of them being a "Right Hyperbolic Cylinder". If you run MGED with "mged -c cylinder.g", then run "make rhc rhc" on the mged> command prompt, it will create one. If you then quit mged and run "dbupgrade -r cylinder.g" and reopen the file with "mged -c cylinder.g", the rhc object will be corrupted (try running "l rhc" in mged before and after).

This task's goal is to reproduce, identify, and fix the bug so that the rhc object doesn't get corrupted. To do this, you'll want to use a debugger like lldb or gdb or Visual Studio (there are tutorials all over the web if you've never used a debugger), or simply use print statements.

See the rt_rhc_import5(), ..export5(), .._import4(), and .._export4() functions as they implement the read/write support.

Code:

  • src/librt/primitives/rhc/rhc.c, <- you'll probably need to modify this file
  • src/librt/primitives/table.c
  • include/rtgeom.h

 

 

Fix elliptical torus triangulation[edit]

BRL-CAD has many 3D object types, one of them being an "Elliptical Torus". If you create a new MGED database and run this sequence of commands, it'll crash due to excessive recursion:

make eto eto
tol norm 1
facetize eto.bot eto

This task's goal is to reproduce, identify, and fix the bug so that detailed eto tessellation completes successfully. To get started, see the rt_eto_tess() function in src/librt/primitives/eto/eto.c and the facetize command logic in libged.

Code:

  • src/librt/primitives/eto/eto.c, <- you'll probably need to modify this file
  • src/libged/facetize/facetize.cpp

 

 

Implement a function that evaluates volume with spherical sampling[edit]

Implement this function:

   int estimate_volume(struct db_i *dbip, 
                       struct directory *dp,
                       size_t min_samples,
                       double confidence);

For this function, you'll want to read up on some of BRL-CAD's basic data structures by looking at headers in the include/rt directory or by reading our API documentation. Calling rt_db_internal() and rt_bound_internal() will get you the bounding box around geometry from which you can calculate a bounding sphere. Once you have the bounding sphere, randomly generate a set of min_samples*2 points on the surface of the sphere. Shoot a ray through those points using rt_shootray(), as in the ray tracing example. Keep track of a volume estimate and keep shooting sets of min_samples rays until the estimate is less than the specified confidence value. Volume of a sphere is (4/3 * pi * r^3) so dividing that by num_samples will give a per-ray factor and multiplying all hit thicknesses by that factor will give a running volume estimate.

References:

 

 

Implement a function to return an object's color[edit]

CAD geometry can have colors specified in a number of ways including directly on that object, in a parent object, and in a lookup table. For this task, you're going to implement a function that reports the color of an object given a path to that object:

   int get_color(struct db_i *dbip, const char *path, struct bu_color *rgb);

You'll need to iteratively consider each object named on the specified path (e.g., "/car/wheel/tire.r/torus") starting with "car" and working your down the path (i.e., 'wheel', 'tire.r', and then 'torus') to 1) see if a color is set on that object and 2) see if that color overrides lower-level colors (i.e., is inherited down the path), and 3) if it's a region object, whether there is a color set in the region table. You'll need to db_lookup() each object on the path to get access to its data.

For this function, you'll want to read up on some of BRL-CAD's basic data structures by looking at headers in the include/rt directory or by reading our API documentation. This task may seem complicated if you're not familiar with C/C++ APIs, data structures, or hierarchical paths, so don't be shy asking questions.

References:

Code References:

  • src/libged/display_list.c
  • src/libged/color/color.c
  • src/librt/prep.c

 

 

Stub in an OpenVDB object[edit]

BRL-CAD has dozens of distinct primitive object types. For this task, you're going to implement the bare minimum to necessary to create a new object with the "make" command in MGED.

The best way to achieve this task is by searching for a keyword for another primitive (e.g., 'grep -r -i superell .') and implementing your new object the same way. Start with the 'make' command itself in src/libged/make/make.c and add "vdb" alongside where you find one of the other primitive types (e.g., superell). To get that to compile, you'll have to add new symbols you've defined into header files (e.g., include/rt/rtgeom.h). You'll eventually need to implement barebones logic in src/librt/primitives/vdb too.

Code:

  • include/rt/defines.h <- needs an ID
  • include/rt/geom.h <- needs an "internal" i.e., in-memory structure
  • src/libged/make/make.c <- needs to recognize "vdb" as a valid type
  • src/librt/primitives/table.cpp <- needs an entry
  • src/librt/primtiives/vdb <- needs a dir
  • src/librt/primitives/vdb/vdb.c <- needs _import5/_export5 callbacks, maybe _describe too

 

 

Documentation and Training[edit]

Tasks related to creating/editing documents and helping others learn more about BRL-CAD

Add missing documentation (for any ONE command)[edit]

BRL-CAD is an extensive system with more than 400 commands and more than a million pages of documentation, but there are approximately 120 commands that are entirely undocumented:

a-d archer asc2g asc2pix bot-bldxf bottest brep_cube brep_simple brickwall btclsh burst bw-a bw-d bwish c-d chan_add clutter contours d-a damdf dauto dauto2 d-bw dconv ddisp d-f dfft d-i dmod double-asc dpeak dsel dsp_add dstat d-u dwin euclid_format euclid_unformat fbgammamod f-d fence fhor f-i g-adrt g-euclid1 g-jack globe g-off i-a i-d i-f ihist imod istat jack-g kurt lowp molecule nmgmodel nmg-sgp off-g pipe pipetest pix2g pix3filter pixcount pixelswap pixembed pixfields pixfieldsep pixflip-fb pixpaste pix-spm pix-yuv plstat pyramid rawbot remapid rlesortmap rletovcr room rtcell rtexample rtfrac rtrad rtsil rtsrv script-tab sketch solshoot sphflake spltest spm-fb ssampview syn tea tea_nmg testfree texturescale torii ttcp tube txyz-pl u-a u-bw u-d u-f umod ustat vcrtorle vegitation wall wdb_example xbmtorle xyz-pl yuv-pix

This task involves writing basic documentation for JUST ONE of those commands in the Docbook XML format. The command documentation should provide a one-sentence description, a detailed paragraph description (200+ words), explanation of all available command-line options, and one or more examples on how to use the command.

Code:

  • doc/docbook/system/man1/en/Makefile.am
  • doc/docbook/system/man1/en/*.xml

 

 

Complete our "Intro to BRL-CAD Modeling" tutorial and extend it[edit]

We've developed two short and simple tutorials for introducing new users to modeling with BRL-CAD.

This task involves doing one of the tutorials (they take about an hour) and then extending it with a new section or making some other improvement. At the end of the tutorial are several optional advanced "exercise left to the reader", for example. Write a half-page step-by-step for one of the exercises left to the reader. Include screenshots and images to make it look nice so the reader is not bored.

Reference:

 

 

Translate "Contributors Guide To BRL-CAD" To Any Language[edit]

People interested in improving BRL-CAD sometimes find themselves lost in a sea of information. In all, BRL-CAD has more than a million words of documentation across hundreds of manual pages, dozens of tutorials and examples, hundreds of wiki pages, dozens of technical papers, and other resources. There are literally thousands of features and this can sometimes pose problems.

In 2013, a team of contributors got to California and worked on an entire book titled "Contributors Guide To BRL-CAD" in just a few days. This great resource needs to be translated to other languages to attract developers from other lingual backgrounds (who don't read English ) to contribute to BRL-CAD.

This task involves translating the chapters/sections of the "Contributors Guide To BRL-CAD" into a language of your choice such as Mandarin, French, Chinese, Spanish, German, Hindi, Arabic, Russian, etc. Chapters/Sections include

  • Feature Overview
  • Working with our Code
  • What code to work on
  • How to contribute
  • .... (Just to name a few )

The output of this task can be a pdf, html, doc, odt or any other document file that contains the translated article.Images in the original document (see link in Reference below) should not be changed ! only text should be.

Reference:

 

 

Write a "BRL-CAD Commands Quick Reference" document[edit]

There is already a command quick reference for BRL-CAD's MGED geometry editing tool, but there is not a similar document for BRL-CAD's 400+ command-line commands.

This task involves writing a quick reference document similar to the MGED quick reference but for BRL-CAD commands. The sheet should minimally include the following commands:

mged, rt*, *-g, g-*, fb*, *fb, nirt, remrt, rtsrv, asc2g, g2asc, dbupgrade, pix*, *pix, *-*, brlman, benchmark

References:

 

 

Doxygen cleanup[edit]

BRL-CAD uses Doxygen for most API documentation but the comment blocks are not optimally set up for Doxygen output.

This task involves cleaning up the Doxygen comments in the library so that useful reports and API documentation automatically generated (correctly, completely, and cleanly). Verify/fix any Doxygen syntax. Verify/fix groups so that functions are organized neatly and all contained within a group. Provide patches that give clean (PDF) output from Doxygen.

References:

 

... doxygen cleanup for LIBBU[edit]

There are approximately 300 documented API function calls in LIBBU.

Code:

  • include/bu.h
  • src/libbu
  • misc/Doxyfile

 

 

... doxygen cleanup for LIBWDB[edit]

There are approximately 100 documented API function calls in LIBWDB.

Code:

  • include/wdb.h
  • include/raytrace.h
  • src/libwdb
  • misc/Doxyfile

 

 

... doxygen cleanup for LIBRT[edit]

There are approximately 1000 documented API function calls in LIBRT.

Code:

  • include/raytrace.h
  • src/librt
  • src/librt/primitives
  • src/librt/comb
  • src/librt/binunif
  • misc/Doxyfile

 

 

 

 

Add images to our wiki page on Volumetric objects[edit]

BRL-CAD provides a couple dozen distinct primitives. Each primitive is defined by a set of parameters. Several of the more complex primitives have a wiki page describing them in more detail with an example on how to create them.

This task involves adding images to our page for the VOL primitive. You'll need to first complete the tutorial and save images for each step. Add the images to the wiki page.

References:

 

 

Fix Image Formatting in BRL-CAD's DocBook Documentation (any ONE large document or 4 smaller documents)[edit]

The majority of BRL-CAD's documentation is defined as DocBook files, from which other formats (HTML, PDF, man page, etc.) can be generated. PDF files present a particular challenge, and have some very specific requirements to achieve "good" formatting.

BRL-CAD's DocBook files need to uniformly use a style of image inclusion that is aware of what "role" the image is supposed to serve. A "basic" image inclusion example looks like this:

 <mediaobject>
   <imageobject>
     <imagedata align="center" fileref="../../lessons/en/images/img.png" format="PNG"/>
   </imageobject>
   <caption>
     <para>
       Caption goes here.
     </para>
   
 </mediaobject>

This task involves switching image inclusions that use the above style to something like the following:

 <mediaobject>
   <imageobject role="html">
     <imagedata align="center" fileref="../../books/en/images/img.png" format="PNG"/>
   </imageobject>
   <imageobject role="fo">
     <imagedata align="center" fileref="../../books/en/images/img.png" format="PNG"/>
   </imageobject>
   <caption>
     <para>
       Caption goes here.
     </para>
   
</mediaobject>

The "role" flag to imageobject provides the opportunity to specify different image formatting options when the output is HTML (role="html") or PDF (role="fo").

The captions should be preserved as above on mediaobjects that have them, but mediaobjects without a caption should also be converted and there is no need to add a caption in such cases.

Any patch that makes changes to the DocBook sources should result in a successful "make doc" build test. This won't generate PDF documents, but it will validate the XML files and produce HTML - remember that introducing breakage means the patch won't be accepted.

Remember, the tasks are simply to do the above conversion for all images in the file or files, not to introduce PDF specific formatting. Formatting fixes will be needed, but they are very much "case by case" and will take both additional time and a working Apache FOP installation, as well as knowledge of how to enable PDF generation. If all image inclusions have been converted successfully and a student is interested in actually fixing the formatting, please discuss it with us on IRC or the mailing list.

References:

  • doc/docbook/books/en/BRL-CAD_Tutorial_Series-VolumeIII.xml

Code:

  • doc/docbook

 

 

Find 5 bugs in OGV[edit]

Online Geometry Viewer is a web based application with which you can see 3D .g models in browser without the use of any plugins. Your task will be to deploy OGV locally and find 5 bugs or errors in it.

Links: https://github.com/BRL-CAD/OGV-meteor/

 

 

Outreach and Research[edit]

Tasks related to community management, outreach/marketing, studying problems, and recommending solutions

Profile NURBS prep performance[edit]

BRL-CAD implements support for rendering of NURBS representation geometry. If you import a solid 3DM or STEP format model into BRL-CAD, it will import as BREP/NURBS geometry. Opening that geometry in BRL-CAD's MGED editor will tell you what objects are available and our 'rt' tool will raytrace it. When geometry is ray traced, it first goes through a "prep" phase and then it starts shooting rays. Our prep phase is entirely unoptimized so we'd like to know where all the time is presently being spent during prep..

This task involves importing some NURBS geometry into BRL-CAD and ray tracing that geometry with a profiler watching our prep performance. Any profiler will do, including gprof, but a performance monitor like oprofile or the Mac "Instruments" application (or Shark) are preferred.

Learning how to use a profiler is beyond the scope of this task, so it make take you considerably longer to provide us with useful information if you've never run a profiler before.

To capture prep performance, you will need to import some fairly complex geometry. You should be able to search google with "filetype:3dm" or "filetype:step" or find something on grabcad.com to import

Running "tops" within mged will tell you what geometry is available for rendering.

Running "rt -o file.png -s32" on the system command line (not inside mged) should minimize the ray overhead or you can specifically isolate the prep phase we care about. Prep is the time between when rt is run where it opens a window until the first pixels are fired and pixels start filling in.

 

 

Continue investigating GMP integration[edit]

BRL-CAD uses a fastf_t typedef for most all math operations that is usually a "double" floating point type. We would like to provide the option for resorting to exact arithmetic if possible by merely redefining fastf_t to a C++ type sufficiently overloaded to behave the same. You should be proficient with C++ operator overloading to take this work on. This task is a continuation of a prior GCI task (read it in full!):

http://www.google-melange.com/gci/task/view/google/gci2012/7946218

This task involves testing compilation with a C++ class with overloaded operators such that vmath macro calls still work as well as a sampling of LIBBN API function calls without major changes to the original code. A perfect example case study would be creating the class then testing whether bn_dist_pt3_pt3() and bn_mat_determinant() compute correctly for values that cannot be exactly represented with floating point arithmetic.

Building on the previous GCI task work, take it to the next step. Try setting a vector to 1/3, 1/3, 1/3 and 0.1, 0.1, 0.1 and get proper values to print. Change the V3ARGS() macro if needed. If that all works, try to get bn_dist_pt3_pt3() to work. Report and discuss your progress.

 

 

Upgrade OpenNURBS, report issues[edit]

BRL-CAD uses a customized OpenNURBS library for advanced geometry but it's out of date. For this task, you're going to download the latest OpenNURBS code and upgrade the sources we bundle. The easiest way is probably to move src/other/openNURBS to src/other/openNURBS.backup, and then put the latest OpenNURBS release into src/other/openNURBS.

Once that's done, you'll need to add the src/other/openNURBS.backup/CMakeLists.txt file and make sure the list of files it has matches the files in src/other/openNURBS. Last but not least, re-run cmake and make sure it compiles. You may need to consult the newer openNURBS makefile to see if there are other edits needed in the CMakeLists.txt file.

Save output from any commands you run because you'll probably encounter an error, and that's okay. Just submit logs of all output so we can figure out next steps.

References:

Code:

  • src/other/openNURBS <- replace existing with latest openNURBS from github

 

 

Design a T-Shirt for BRL-CAD[edit]

This task involves designing a T-Shirt for BRL-CAD. Use your designing skills to design a T-Shirt for BRL-CAD. You can use the current BRL-CAD logo, or you may tweak it. Be creative while designing this T-Shirt. It would be good if the design has some special meaning.

Logo References

 

 

Design a coffee mug for BRL-CAD[edit]

This task involves designing a coffee mug for BRL-CAD. Make it look good or at least interesting, and make it in BRL-CAD. Look over some coffee mug designs before starting to work on this. Verify that your mug is valid geometry by running the "rtcheck" command.

Logo References

 

 

Design BRL-CAD sticker[edit]

This task involves designing a BRL-CAD sticker. The design should be simple and sleek. The concept of sticker should be clear and also it should be creatively presented. Get inspired from some sticker designs but choose your own imagination while designing the sticker. There is no bound for shape of sticker, it can be rectangular, circular or even irregular. The only thing that matters is that it should look good.

Logo References

 

 

Design a wallpaper / desktop image for BRL-CAD[edit]

This task involves designing a desktop background for BRL-CAD enthusiasts. The main idea of your wallpaper should be to showcase one or more features of BRL-CAD. Be intentional and able to defend/describe your choice of color, layout, and other aspects of the wallpaper design.

Try to make sure the wallpaper works across a broad selection of screen resolutions.

Search the web for wallpapers inspiration such as:

Logo References

 

 

Model a Lightcycle in BRL-CAD using CSG[edit]

The movie Tron is an iconic computer graphics film that used CSG primitives for a majority of the movie's 3D virtual world. The film is famous for "lightcycle" vehicles that were allegedly modeled using 57 primitives and/or Boolean operations. For this task, see if you can recreate the masterpiece in BRL-CAD.

See this lightcycle discussion thread

 

 

Quality Assurance[edit]

Tasks related to testing and ensuring code is of high quality

Fix single-precision floating point crash[edit]

By default, all of BRL-CAD compiles using double-precision floating point arithmetic. We provide a simple typedef, however, that converts almost the entire system over to single-precision floating point. This compilation mode was recently cleaned up and tested, but a bug was found. The problem is reproduced very simply by compiling in single precision mode and running our "rt" ray tracer tool.

To compile in single precision, edit the include/bn.h header file and change the fastf_t typedef from double to float. To reproduce the bug, compile BRL-CAD and write this out to a text file named star.view:

viewsize 2.500000000e+05;
eye_pt 2.102677960e+05 8.455500000e+04 2.934714650e+04;
viewrot -6.733560560e-01 6.130643360e-01 4.132114880e-01 0.000000000e+00
        5.539599410e-01 4.823888300e-02 8.311441420e-01 0.000000000e+00
        4.896120540e-01 7.885590550e-01 -3.720948210e-01 0.000000000e+00
        0.000000000e+00 0.000000000e+00 0.000000000e+00 1.000000000e+00 ;
start 0;
end;

Then run rt feeding it that view script as input. This is an example how to run within the gdb debugger:

gdb path/to/bin/rt
...
(gdb) run -F/dev/X -M .cmake/share/db/star.g all < star.view

At this point, rt should crash due to an infinite recursion. A backtrace in the debugger will show lots and lots of calls to rt_shootray() and light_hit().

This task involves investigating and preventing the crash. Provide a patch that fixes the bug.

References:

  • man gdb
  • brlman rt

Code:

  • src/librt/shoot.c
  • src/liboptical/sh_light.c

 

 

Fix closedb[edit]

BRL-CAD geometry editor application (mged) has several hundred commands including two very simple commands for opening and closing a geometry database file. While the user rarely ever needs to close the file, as all changes are always immediately saved, it can be of use to scripting applications. However, at some point in the recent past, the closedb command was horked. It's undoubtedly something very simple but we haven't bothered to look due to other priorities. You can fix it. If you run these simple steps within graphical mged, you should see how commands stop working after calling closedb:

 mged> opendb test.g y
 mged> make sph sph
 mged> l sph
 mged> closedb
 mged> make sph sph
 mged> opendb test.g
 mged> l sph
 mged> exit

Provide a patch that fixes the bug or tell us which SVN revision introduced the bug. Make sure you can reproduce the bug before claiming this task, which presumes you know how to download/install BRL-CAD from a source distribution.

Code:

  • src/mged/mged.c

 

 

Create a utility library (LIBBU) API unit test[edit]

There are more than 300 library functions in our core LIBBU library. As a core library used by nearly every one of BRL-CAD's tools, testing those functions for correct behavior is important.

This task involves implementing new unit tests for any of LIBBU's source files that do not already have a unit test defined. The test should run all of the public functions and be hooked into our build system. We have lots of existing unit tests to follow as examples.

References:

  • include/bu.h
  • src/libbu/*.c
  • src/libbu/tests/*.c

Code:

  • src/libbu/tests/[TEST].c
  • src/libbu/tests/CMakeLists.txt

 

 

Create Numerics library (LIBBN) API unit tests[edit]

There are more than 300 library functions in our core LIBBN library. As a core library used by nearly every one of BRL-CAD's tools, testing those functions for correct behavior is important.

This task involves implementing new unit tests for any of LIBBN's source files that do not already have a unit test defined. The test should run all of the public functions and be hooked into our build system. We have lots of existing unit tests to follow as examples.

References:

  • include/bn.h
  • include/plot3.h
  • include/vmath.h
  • src/libbn/*.c
  • src/libbn/tests/*.c <-- check this directory for examples
  • src/libbu/tests/*.c <-- Note: Also check this too for more examples.

Code:

  • src/libbn/tests/[TEST].c
  • src/libbn/tests/CMakeLists.txt

Note A valid task will constitute writing a basic test for each function in the following libbn/ files.

 

... unit tests for LIBBN anim.c[edit]

 

 

... unit tests for LIBBN axis.c[edit]

 

 

... unit tests for LIBBN qmath.c[edit]

 

 

... unit tests for LIBBN rand.c[edit]

 

 

... unit tests for LIBBN vector.c[edit]

 

 

 

 

Find, reliably reproduce, and report any bug in Archer[edit]

Archer is our new modeling interface and a soon to merge with our long-standing MGED geometry editor. It undoubtedly has bugs. It's your job to find one, but do so in a manner that is so obvious that one of the other devs will be able to instantly reproduce the bug given your specific instructions. Find a way to make archer crash, become unresponsive, or otherwise behave incorrectly. You will have to explore the tool with minimal documentation.

This task involves filing a bug report with verifiable and reproducible steps that clearly demonstrate the bug. It can't be a bug already reported or otherwise documented nor can it be merely behavior you don't like.

References:

 

 

Reproduce any 10 unconfirmed open bug reports[edit]

BRL-CAD presently has approximately 75 open bug reports of which 50 are unassigned. Read the comments and status to see if the bug has been confirmed/reproduced.

This task involves going through those reports and REPRODUCE at least 10 of the ones that have not been confirmed. When you can reproduce the issue being reported, you'll comment on the thread to state as much and attach any data you used to reproduce the crash.

References:

 

 

User Interface[edit]

Tasks related to user experience research or user interface design and interaction

Create an ISST screenshot or animation[edit]

Everyone loves to see screenshots and animations of software in action. We use both in our marketing and outreach. See some of the examples below that we already have.

Create an awesome screenshot and/or animation of our 'isst' tool in action. It's an interactive geometry viewer interface. It should be graphically interesting and give some sense of capability. You should import a visually complex and interesting model with LOTS of polygons and detail. Note you may have to go through some or the MGED tutorials (see Docs on our website).

References:

 

 

Categorize commands into a spreadsheet[edit]

BRL-CAD is a suite of more than 400 commands, processing tools, image tools, geometry converters, and more. MGED also has a command-line with hundreds of commands too. Help us reorganize one of those command sets.

This task involves creating a spreadsheet that lists all commands and groups them together into a finite set of categories or labels. This spreadsheet will help us identify places where commands can be consolidated, commands we might want to consider removing, common groupings for documentation, etc.

 

 

Design a Cover Photo for Facebook (and other social media)[edit]

BRL-CAD website and marketing materials are constantly undergoing change. Effective marketing requires well designed and attractive imagery. Imagery ideally should showcase some feature of BRL-CAD, some highlight, something visually interesting and compelling.

References:

 

 

Create a video for BRL-CAD[edit]

Watching someone else use software is incredibly helpful to some. Create a screen-cast video for BRL-CAD that showcases some feature, goes over steps involved in creating some model, or shows how to accomplish some other task.

You'll need to install BRL-CAD on your computer and use it in the video. Create or import some model and make a recording.

 

 

When You're Done[edit]

For non-code, just send us your file(s). For code changes, you will be expected to provide a patch file. Make sure you read your patch file before submitting it. Make sure your patch file will apply cleanly to an unmodified checkout of BRL-CAD:

svn co https://brlcad.svn.sourceforge.net/svnroot/brlcad/brlcad/trunk brlcad.edit
cd brlcad.edit
# make changes
svn diff > ~/my.patch
# read ~/my.patch file with text editor
cd ..
svn co https://brlcad.svn.sourceforge.net/svnroot/brlcad/brlcad/trunk brlcad.fresh
cd brlcad.fresh
patch -p0 < ~/my.patch
# submit your patch file to our patches tracker