Stub in a new 'mesh' command for creating/editing NMG and BoT polygonal mesh geometry

Stub in a new 'mesh' command for creating/editing NMG and BoT polygonal mesh geometryBRL-CAD

Status: ClosedTime to complete: 100 hrs Mentors: Mihai Neacsu, IshwerdasTags: geometry, C, polygonal mesh, code, function

Our LIBGED geometry editing library contains lots of small modular commands that are made available in mged and archer. We'd like to have a command that lets users create and edit polygonal meshes (BoT and NMG).

This task involves stubbing in a new 'mesh' command. It doesn't need to do anything initially other than print a usage statement and actually work in both mged and archer when you run the command. Figuring out the latter is the majority of work for this task, but don't worry -- there are lots of examples to follow.

You'll want to download our latest SVN sources or update the VM image following http://brlcad.org/wiki/Compiling and compile BRL-CAD.

Then make your edits, make sure they compile and work, and submit them as a unified patch file (svn diff my_changes.patch).

References:

src/libged/*.c -- look here for hundreds of examples
http://en.wikipedia.org/wiki/Polygon_mesh
Check out some other programs that have a command line interface

Modify:

src/libged/mesh.c -- you create this
src/libged/CMakeLists.txt -- edit this to add your new file
src/mged/setup.c -- where you hook into mged
src/libtclcad -- where you hook into archer
src/tclscripts -- where you hook up a help string

Uploaded Work

File name/URL	File size	Date submitted
task-21-stub-in-mesh.diff	5.4 KB	December 09 2014 07:52 UTC
task-21-stub-in-mesh.diff	6.0 KB	December 09 2014 15:45 UTC
task-21-stub-in-mesh-v2.diff	6.0 KB	December 10 2014 03:56 UTC

Comments

Andromeda Galaxyon December 9 2014 07:51 UTCTask Claimed

I would like to work on this task.

Sean on December 9 2014 07:51 UTCTask Assigned

This task has been assigned to Andromeda Galaxy. You have 100 hours to complete this task, good luck!

Andromeda Galaxyon December 9 2014 07:52 UTCReady for review

The work on this task is ready to be reviewed.

Andromeda Galaxyon December 9 2014 07:54 UTCClaim Removed

The claim on this task has been removed, someone else can claim it now.

Andromeda Galaxyon December 9 2014 14:12 UTCTask Claimed

I would like to work on this task.

Ch3ck on December 9 2014 14:19 UTCTask Assigned

This task has been assigned to Andromeda Galaxy. You have 100 hours to complete this task, good luck!

Andromeda Galaxyon December 9 2014 15:45 UTCReady for review

The work on this task is ready to be reviewed.

Andromeda Galaxyon December 9 2014 15:46 UTCDiff files

The first diff was uploaded previously before I fully understood the task; the second one is the correct final one.

Sean on December 10 2014 03:34 UTCTask Needs More Work

One of the mentors has sent this task back for more work. Talk to the mentor(s) assigned to this task to satisfy the requirements needed to complete this task, submit your work again and mark the task as complete once you re-submit your work.

Sean on December 10 2014 03:49 UTCfew issues

Few issues noted:

The file header on mesh.c is wrong in several places (title, year, doxygen, and comment).

Usage statement currently will print "Usage: obj_name [-b|-n] [+|-]face_description..." noting that the command name is missing.

Suggest a subcommand argument to be consistent with other commands instead of using +|-, which will allow for the inevitable introduction of other subcommands.

the gedWrapper line doesn't look right, probably should be 0 0 1 0 to indicate that the file has been edited and will need to be saved.

face_description is very much undefined (and almost certainly inadequate for either bot or nmg) ... we may need a design task to fully think through some examples for how this will work.

Andromeda Galaxyon December 10 2014 03:53 UTCface_description

I'm addressing the other issues right now; however, for face_description, my original thought was tht it might look something like the way that faces are specified in the get/put representations: {loop1, loop2, ...} where each loop is {v1, v2, ...}.

Andromeda Galaxyon December 10 2014 03:56 UTCReady for review

The work on this task is ready to be reviewed.

Sean on December 10 2014 05:41 UTCTask Closed

Congratulations, this task has been completed successfully.

Sean on December 10 2014 05:47 UTCIt might work

... it's still work applying some test-driven development principles to actually work through some of the design issues, before spending time implementing a lot of argument parsing that we might need to change regardless. What is written for get/put is highly opaque and implicit. I strongly doubt that would make for an intuitive interface, but I could be wrong. That's the point of working through a few examples. I'd like to see what a simple box would look like in bot and nmg format, then a box with a hole through it for both (the whole creates interior loops for the nmg, but not for the bot. I'll schedule a GCI task for exactly that.