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If you want to work on '''computer-aided design (CAD), geometry, simulation, analysis, or graphics''', you've come to the right place!  Help us improve open source CAx.
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The list of possible projects below should serve as a good starting point for new developers that would like to get involved in working on BRL-CAD. The ideas below range from the very hard and math intense to the very easy, see the link to each for more details.  You are also welcome to scale the scope of the project up or down as needed as the ideas suggested below ''are merely starting points''.
  
{|align="center" width="62%"
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{|align="right"
  |align="center" |[http://brlcad.org/w/index.php?title=Google_Summer_of_Code/Project_Ideas#BRL-CAD_Projects http://brlcad.org/images/logo/cutout_sticker_256.png]
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  |[[Image:BRL-CAD_Priorities.png|thumb|left|256px|BRL-CAD Priorities]]
|colspan=2 align="center" |Under development for 30+ years, it's big, it's complicated, it's powerful.  BRL-CAD will consider just about any project that relates to computer graphics or existing infrastructure.
 
 
  |}
 
  |}
  
We consider proposals for all skill levels  ranging from simple to crazy hard and everything in between.  [https://lists.sourceforge.net/lists/listinfo/brlcad-devel Introduce yourself], and we'll help you plan one right for you.
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Be sure to read up on our [[Summer_of_Code/Application_Guidelines|application process]] for getting started with your proposal submission if you have not done so already including our [[Summer_of_Code/Checklist|checklist]]. See the diagram at the bottom of this page for an overview of our major project focus areas.
  
Remember that project descriptions are just ''initial ideas''.  You must expand with [[Summer_of_Code/Application_Guidelines|considerably more detail]].  Change the goals to fit your experience and interests.  See our '''[[Summer_of_Code/Checklist|checklist]]''' to get started.
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= Project Categories =
  
'''Project titles link to a page with more details.'''
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== High-priority Space Projects ==
  
= BRL-CAD Projects =
+
BRL-CAD has been used to visualize Hubble up in orbit (before it was launched), simulate light transport (multispectral analyses), model Earth's interior layers (education), and much more but there is lots of work that would really help make BRL-CAD more readily used for space work.  Given the mission of SOCIS, these are all naturally high-priority.
  
== High Priority Topics ==
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{| border=1 bgcolor=#444444
 
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!Idea
{| bgcolor=#fff width=100%
+
!Languages
!
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!Impact
!align=center|Languages
+
!Difficulty
!align=center|Difficulty
 
 
|-
 
|-
|align=left width=62%|'''[[Convert MGED from Tk to Qt]]:'''  Transition BRL-CAD's graphical applications from the Tk toolkit to the Qt toolkit. 
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|'''[[Astronomical units]]:'''  We already go "big", but accurately modeling at a galactic scale redefines that notion...
|align=center|C/C++/Tcl/Qt
+
|C
|align=center|MEDIUM
+
|BIG
|-
+
|EASY
|width=62%|'''[[Annotations]]:'''  Implement support for 2D annotations, labels that can be added to geometry.
 
|align=center|C/C++
 
|align=center|MEDIUM
 
|}
 
 
 
 
 
== Rendering & Scientific Analysis ==
 
 
 
{| bgcolor=#fff
 
!
 
!align=center|Languages
 
!align=center|Difficulty
 
 
|-
 
|-
|width=62%|'''[[Shader Enhancements]]:'''  We have a functioning custom shader system in BRL-CAD, but there are now folks that specialize and there's lot of room for improvements.
+
|'''[[Bending light]]:'''  Think gravity wells and satellite cameras.
|align=center|C
+
|C
|align=center|EASY
+
|BIG
 +
|MEDIUM
 
|-
 
|-
|width=62%|'''[[Material and Shader Objects]]:'''  This one is a biggie but easy.  Implement new object entities for describing shaders and material properties, use them during ray tracing.
+
|'''[[Celestial mechanics particle system]]:'''  Simulate solar systems and galaxies.
|align=center|C
+
|C/C++
|align=center|EASY
+
|BIG
 +
|MEDIUM
 
|-
 
|-
|width=62%|'''[[GUI Integration of Analysis Tools]]:'''  There are a ''lot'' of visualization tools in BRL-CAD, but most aren't integrated with the GUI.  Visualizing directly within the GUI would improve usability.
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|'''[[Non-vacuum gravity simulator]]:'''  Simulate falling to earth.
|align=center|C
+
|C/C++
|align=center|MEDIUM
+
|BIG
 +
|MEDIUM
 
|-
 
|-
|width=62%|'''[[Generalized abstracted spacial partitioning capability]]:''' Need more be said? If you're familiar with BSPs, KD trees, and grid structures, then this one is for you.
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|'''[[Polarization]]:'''  We already do multispectral ray tracing, but don't simulate polarization effects.  Implement ray splitting and filtering.
|align=center|C
+
|C
|align=center|HARD
+
|BIG
 +
|HARD
 
|-
 
|-
|width=62%|'''[[High Dynamic Range Support]]:'''  We don't have displays supporting this yet, but that's never stopped us beforeImplement support for images with more than 8-bits per channel.
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|'''[[Density functions]]:'''  Accurately represent everything from atmosphere to bone.  Implement support for parametric density functions for homogenous materials.
|align=center|C and/or C++
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|C
|align=center|EASY
+
|BIG
 +
|HARD
 +
|}
 +
 
 +
 
 +
== Rendering & Analysis Projects ==
 +
 
 +
Raytracing is at the heart of all that is BRL-CAD.  The 'rt' application was the world's first distributed parallel ray tracer, implemented in early 80's, and it's backed by our powerful LIBRT library.  We're the best as full path shotlines (shooting all the way through geometry, not just first hit) and can handle crazy big geometry very efficiently, very fastIt's how we perform geometric analysis, generate images, perform simulations, and more.
 +
 
 +
{| border=1 bgcolor=#444444
 +
!Idea
 +
!Languages
 +
!Impact
 +
!Difficulty
 
|-
 
|-
|width=62%|'''[[Analysis Library]]:'''  There are various tools in BRL-CAD for calculating weights, moments of inertia, and more.  They're stand-alone applications.  Turn them into a library.
+
|'''[[Material and Shader Objects]]:'''  This one is a biggie but easy.  Implement new object entities for describing shaders and material properties, use them during ray tracing.
|align=center|C
+
|C
|align=center|HARD
+
|HUGE
 +
|EASY
 
|-
 
|-
|width=62%|'''[[Celestial mechanics particle system]]:'''  Simulate solar systems and galaxies.
+
|'''[[High Dynamic Range Support]]:'''  We don't have displays supporting this yet, but that's never stopped us before.  Implement support for images with more than 8-bits per channel.
|align=center|C/C++
+
|C and/or C++
|align=center|MEDIUM
+
|BIG
 +
|EASY
 
|-
 
|-
|width=62%|'''[[Non-vacuum gravity simulator]]:'''  Simulate falling to earth.
+
|'''[[Vector output from raytracing]]:'''  Huge impact here if you can update one or more of our raytracers to provide vector output instead of raster.  Perhaps render directly to PDF or SVG.
|align=center|C/C++
+
|C and/or C++
|align=center|MEDIUM
+
|HUGE
 +
|EASY
 
|-
 
|-
|width=62%|'''[[Polarization]]:'''  We already do multispectral ray tracing, but don't simulate polarization effects.  Implement ray splitting and filtering.
+
|'''[[Analysis Library]]:'''  There are various tools in BRL-CAD for calculating weights, moments of inertia, and moreThey're stand-alone applicationsTurn them into a library.
|align=center|C
+
|C
|align=center|HARD
+
|HUGE
|-
+
|HARD
|width=62%|'''[[Density functions]]:'''  Accurately represent everything from atmosphere to boneImplement support for parametric density functions for homogenous materials.
 
|align=center|C
 
|align=center|HARD
 
|-
 
|width=62%|'''[[Bending light]]:'''  Think gravity wells and satellite cameras.
 
|align=center|C
 
|align=center|MEDIUM
 
|-
 
|width=62%|'''[[Appleseed renderer integration]]:'''  Appleseed is rendering infrastructure used by the film industry to make pretty picturesMake it shoot rays at our native geometry with our ray trace library.
 
|align=center|C
 
|align=center|MEDIUM
 
 
|}
 
|}
  
  
== Web Development ==
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== Web Development Projects ==
  
{| bgcolor=#fff
+
We're generally less interested in web development projects because the developer rarely sticks around after development is over.  We're not interested in web code, we're interested in people.  If you're willing to work on your project long after this summer is over (i.e., joining the project) and are willing to make a long-term commitment to BRL-CAD, then we welcome your web development project idea.
!
+
 
!align=center|Languages
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{| border=1 bgcolor=#444444
!align=center|Difficulty
+
!Idea
 +
!Languages
 +
!Impact
 +
!Difficulty
 
|-
 
|-
|width=62%|'''[[Benchmark Performance Database]]:'''  BRL-CAD's Benchmark has been used for two decades to compare performance  across configurations.  Build a database website.  
+
|'''[[Materials Database]]:'''  Create a Materials Database web site for collecting, managing, and providing programmatic interfaces to material properties.
|Depends (likely PHP or Python)
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|Depends
|align=center|EASY
+
|BIG
 +
|MEDIUM
 
|-
 
|-
|width=62%|'''[[Materials Database]]:'''  Create a Materials Database web site for collecting, managing, and providing programmatic interfaces to material properties.
+
|'''[[Benchmark Performance Database]]:'''  BRL-CAD's Benchmark has been used for two decades to compare performance  across configurations.  Build a database website.  
|Depends (likely PHP or Python)
+
|Depends
|align=center|MEDIUM
+
|BIG
 +
|MEDIUM
 
|}
 
|}
  
  
== Geometry ==
+
== Geometry Conversion Projects ==
  
{| bgcolor=#fff width=100%
+
When it comes to geometry conversion, STEP and IGES are the priority.  STEP is an absurdly complicated format, but we're one of the first open source projects to implement a working importer.  IGES is a much older standard, but more time-tested too.  Both have a variety of potential high-priority projects associated with the.
!
+
 
!align=center|Languages
+
{| border=1 bgcolor=#444444
!align=center|Difficulty
+
!Idea
 +
!Languages
 +
!Impact
 +
!Difficulty
 
|-
 
|-
|align=left width=62%|'''[[NURBS Editing Support]]:'''  BRL-CAD doesn't currently have support for editing NURBS primitivesFix that.
+
|'''[[STEP Libraries]]:'''  We took over the NIST STEP Class Library (SCL) project during our development of our g-step exporterIt needs a lot of cleanup.
|align=center|C/Tcl
+
|C/C++
|align=center|MEDIUM
+
|HUGE
 +
|EASY
 
|-
 
|-
|width=62%|'''[[Overlap tool]]:''' Resolving geometric interferences (aka overlaps) is a common geometry editing activity. Design an awesome GUI for resolving conflicts.
+
|'''[[STEP exporter]]:'''  We have an importer, we need a comprehensive exporter with support for implicit CSG, NURBS, or polygonal mesh geometry.
|align=center|Tcl
+
|C/C++
|align=center|EASY
+
|HUGE
 +
|EASY
 
|-
 
|-
|align=left width=62%|'''[[Vector Drawings from NURBS]]:'''  Huge impact here if you can update one or more of our raytracers to provide vector output instead of rasterPerhaps render directly to PDF or SVG.
+
|'''[[STEP importer improvements]]:'''  We have an importer, but it's preliminaryAdd support for importing hierarchy information, polygonal geometry, and implicit geometry.
|align=center|C and/or C++
+
|C/C++
|align=center|EASY
+
|HUGE
 +
|MEDIUM
 
|-
 
|-
|align=left width=62%|'''[[Plate Mode NURBS raytracing]]:'''  Imported NURBS geometry often does NOT enclose space (i.e., not solid), so add support for specifying an implicit thickness.
+
|'''[[IGES import improvements]]:'''  We have extensive support for the International Geometry Exchange Standard (IGES) with our g-iges and iges-g converters, but they need updating.
|align=center|C/C++
+
|C
|align=center|HARD
+
|HUGE
 +
|MEDIUM
 
|-
 
|-
|width=62%|'''[[STEP exporter]]:'''  We have an importer, we need a comprehensive exporter with support for implicit CSG, NURBS, or polygonal mesh geometry.
+
|'''[[Geometry Conversion Library]]:'''  Probably our biggest open source asset is our extensive collection of importers and exporters.  Turn them all into a universal conversion library.  
|align=center|C/C++
+
|C/C++
|align=center|EASY
+
|HUGE
 +
|EASY
 
|-
 
|-
|width=62%|'''[[STEP importer improvements]]:'''  We have an importer, but it's preliminaryAdd support for importing hierarchy information, polygonal geometry, and implicit geometry.
+
|'''[[Voxelize]] command:'''  Convert geometry into voxel data sets by shooting a grid of raysThe finite element analysis and volumetric rendering folks will love you.
|align=center|C/C++
+
|C
|align=center|MEDIUM
+
|BIG
|-
+
|EASY
|width=62%|'''[[STEP AP 242 Parser]]:''' We already parse a subset of AP203, but the new kid on the block is AP242Make AP242 work with BRL-CAD's step-g importer.  
+
|}
|align=center|C++
+
 
|align=center|HARD
+
 
 +
== Geometry Processing Projects ==
 +
 
 +
As part of our new GUI development efforts, a lot of code had to be moved out of application space into a library.  That library is our geometry editing library, LIBGED. A lot of time, attention, and emphasis is going on there to make sure that all of our core functionality is reusable by applicationsMore than 100k lines of code have already moved, but there's still a lot more work needed.
 +
 
 +
{| border=1 bgcolor=#444444
 +
!Idea
 +
!Languages
 +
!Impact
 +
!Difficulty
 
|-
 
|-
|width=62%|'''[[IGES import improvements]]:''' We have extensive support for the International Geometry Exchange Standard (IGES) with our g-iges and iges-g converters, but they need updating.
+
|'''[[GED Transactions]]:''' Migrating functionality from our MGED geometry editor into our LIBGED library provided excellent code reuse, but now we need transactions so that actions can be undone.
|align=center|C
+
|C
|align=center|MEDIUM
+
|HUGE
 +
|EASY
 
|-
 
|-
|width=62%|'''[[Geometry Conversion Library]]:'''  Probably our biggest open source asset is our extensive collection of importers and exporters.  Turn them all into a universal conversion library.  
+
|'''[[Geometric Constraint Solver]]:'''  Our LIBPC parametric constraint library is the work-in-progress foundation of being able to validate and describe geometry relationships.
|align=center|C/C++
+
|C/C++
|align=center|EASY
+
|HUGE
 +
|HARD
 +
|}
 +
 
 +
 
 +
== NURBS (Non-Uniform Rational B-Splines) Projects==
 +
 
 +
BRL-CAD has recently implemented raytracing support for NURBS-based boundary representation geometry.  It's one of our '''''hot-topic priority focus areas''''' with ''high'' impact and ''high'' visibility.  They are also pretty hard so be careful to have sufficient familiarity and lots of milestones.
 +
 
 +
{| border=1 bgcolor=#444444
 +
!Idea
 +
!Languages
 +
!Impact
 +
!Difficulty
 
|-
 
|-
|width=62%|'''[[Voxelize]] command:'''  Convert geometry into voxel data sets by shooting a grid of raysThe finite element analysis and volumetric rendering folks will love you.
+
|'''[[NURBS Intersections]]:'''  Evaluate the intersection of two NURBS surfacesYou'll get a 3D curve or a point, line segment, or even a plane depending how the surfaces overlap.
|align=center|C
+
|C/C++
|align=center|EASY
+
|HUGE
 +
|HARD
 
|-
 
|-
|width=62%|'''[[COLLADA Importer]]:'''  Create an importer for the COLLADA file format.
+
|'''[[NURBS Tessellation]]:''' Given a NURBS object (i.e., a collection of NURBS surfaces that enclose space), evaluate a polygonal mesh. It has to be fast.
|align=center|C/C++
+
|C/C++
|align=center|MEDIUM
+
|HUGE
 +
|MEDIUM
 
|-
 
|-
|width=62%|'''[[X3D Importer]]:'''  Create an importer for the X3D file format.
+
|'''[[Implicit to NURBS conversion]]:'''  We implement lots of primitives like sphere and torus defined with implicit parameters.  Given one of our implicit primitives, describe it using NURBS surfaces.
|align=center|C/C++
+
|C/C++
|align=center|MEDIUM
+
|HUGE
 +
|MEDIUM
 
|-
 
|-
|width=62%|'''[[OpenSCAD Importer]]:'''  Create an importer for OpenSCAD's format.
+
|'''[[Plate Mode NURBS raytracing]]:'''  Imported NURBS geometry often does NOT enclose space (i.e., not solid), so add support for specifying an implicit thickness.
|align=center|C/C++
+
|C/C++
|align=center|EASY
+
|HUGE
|-
+
|HARD
|width=62%|'''[[OpenSCAD Exporter]]:'''  Create an exporter for OpenSCAD's format.
 
|align=center|C/C++
 
|align=center|EASY
 
 
|}
 
|}
  
  
== Performance & Quality ==
+
== Graphical User Interface (GUI) Projects ==
  
{| bgcolor=#fff
+
The primary environment in which users interact with BRL-CAD geometry is the MGED geometry editor.  The "next generation" interface for MGED, dubbed ''Archer'', has been under development for some time but there is a lot of  functionality that still needs to be migrated and new features needed by MGED, Archer, or both.
!
+
 
!align=center|Languages
+
{| border=1 bgcolor=#444444
!align=center|Difficulty
+
!Idea
 +
!Languages
 +
!Impact
 +
!Difficulty
 
|-
 
|-
|align=left width=62%|'''[[OpenCL GPGPU Raytracing]]:''' We have about two dozen primitives that need to have a ray-object intersection function converted from C to OpenCL.
+
|'''[[New Cross-Platform 3D Display Manager]]:''' BRL-CAD uses '''''display managers''''' for visualizing 3D geometry in a window.  We want one that uses a cross-platform toolkit such as Qt or OGRE.
|align=center|C/C++
+
|C/C++
|align=center|MEDIUM
+
|HUGE
 +
|MEDIUM
 
|-
 
|-
|align=left width=62%|'''[[Coherent Raytracing]]:''' Our current raytrace pipeline dispatches and processes one ray at a time.  Send bundles and convert the pipeline into phases.  
+
|'''[[New Cross-Platform 2D Framebuffer]]:''' BRL-CAD uses '''''framebuffers''''' to display 2D imagery.  The merits of having a single interface for most platforms is self-evident.
|align=center|C/C++
+
|C/C++
|align=center|MEDIUM
+
|HUGE
 +
|EASY
 
|-
 
|-
|align=left width=62%|'''[[NURBS Booleans]]:'''  We have NURBS surface-surface intersections working.  Now we're using them to create evaluated forms of our CSG geometryMake it more robust and faster.
+
|'''[[GUI Integration of Analysis Tools]]:'''  There are a ''lot'' of visualization tools in BRL-CAD, but most aren't integrated with the GUIVisualizing directly within the GUI would improve usability.
|align=center|C/C++
+
|C
|align=center|HARD
+
|BIG
 +
|MEDIUM
 
|-
 
|-
|align=left width=62%|'''[[NURBS Optimization and Cleanup]]:'''  We have a fantastic implementation of NURBS evaluation but haven't gone back to clean up or speed it up.  Make it pretty and fast.
+
|'''[[Level of Detail Wireframes]]:''' Geometry is drawn with fixed wireframe detail which can screw performance and make shape recognition difficult. Detail needs to adjust based on view size.
|align=center|C/C++
+
|C
|align=center|MEDIUM
+
|HUGE
 +
|EASY
 
|}
 
|}
  
  
== Infrastructure ==
+
== Code Refactoring Projects ==
  
{| bgcolor=#fff
+
BRL-CAD has more than a million lines of code so we have to continually refactor and clean up code for maintainability.  Cruft happens.  These projects help reduce the complexity and make things better. They're not very hard at all, but exceedingly valuable to our project vitality.
!
+
 
!align=center|Languages
+
{| border=1 bgcolor=#444444
!align=center|Difficulty
+
!Idea
 +
!Languages
 +
!Impact
 +
!Difficulty
 
|-
 
|-
|width=62%|'''[[Geometric Constraint Solver]]:'''  Our LIBPC parametric constraint library is the work-in-progress foundation of being able to validate and describe geometry relationships.
+
|'''[[Code Reduction]]:'''  BRL-CAD is more than 1M lines of code.  Approximately 10% of that is duplication.  Help reduce that percentage.
|align=center|C/C++
+
|C
|align=center|HARD
+
|BIG
 +
|EASY
 
|-
 
|-
|width=62%|'''[[Consolidate image processing]]:'''  We have 100+ image processing tools that independently read and write file data.  Needs much reuse love.
+
|'''[[Consolidate image processing]]:'''  We have 100+ image processing tools that independently read and write file data.  Needs much reuse love.
|align=center|C
+
|C
|align=center|EASY
+
|HUGE
 +
|EASY
 
|-
 
|-
|width=62%|'''[[Astronomical units]]:'''  We already go "big", but accurately modeling at a galactic scale redefines that notion...
+
|'''[[Fix Bugs]]:'''  We take pride in our breadth of functionality and time-tested stabilityWe still have bugsIdentify some and fix 'em!
|align=center|C
+
|C
|align=center|EASY
+
|DEPENDS
|-
+
|EASY
|width=62%|'''[[Point Clouds]]:''' BRL-CAD has a basic point cloud primitiveBeef it up, make it faster, maybe integrate with the Point Cloud Library (PCL) for evaluation.
 
|align=center|C/C++
 
|align=center|MEDIUM
 
|-
 
|width=62%|'''[[Annotations]]:'''  Implement support for 2D annotations, labels that can be added to geometry.
 
|align=center|Perl
 
|align=center|EASY
 
 
|}
 
|}
  
  
== <An Idea of Your Own> ==
+
== <AN IDEA OF YOUR OWN> ==
  
Do you have an idea of your own? Maybe you need [http://brlcad.org/~sean/ideas.html more ideas] to inspire you? We're very open to areas of academic research, industry applications, and ideas that get you hooked on open source CAD development.
+
Do you have an idea of your own? [[Mailing Lists|Let us know]] and maybe we'll like it too.  We're very open to new ideas, areas of academic research, industry applications, and any other ways that may help get you hooked on BRL-CAD development.  Just remember that BRL-CAD is a solid modeling CAD suite so keep that in mind when scoping your project.  
  
 
Requirements:
 
Requirements:
  
* Passion for the task being suggested
+
*Passion for the task being suggested
 +
*Buy-in from one of the existing developers
  
  
 
= Mentors =
 
= Mentors =
  
Contact Sean on the brlcad-devel mailing list or via IRC to begin discussing your SOCIS project proposal:
+
BRL-CAD operates under group mentorship.  That means you can contact anyone, not just the person assigned to you, for assistance.  The mailing list and IRC channel are the preferred communication methods.
  
 
* Christopher Sean Morrison
 
* Christopher Sean Morrison
 
** brlcad on irc.freenode.net
 
** brlcad on irc.freenode.net
 +
** Org admin, core dev, open source project lead
 +
 +
* Erik Greenwald
 +
** ``Erik on irc.freenode.net
 +
** Org admin, core dev
 +
 +
* Cliff Yapp
 +
** starseeker on irc.freenode.net
 +
** Mentor, core dev
 +
 +
* Daniel Rossberg
 +
** d_rossberg on irc.freenode.net
 +
** Mentor, core dev, math expert
 +
 +
* Dave Loman
 +
** dloman on irc.freenode.net
 +
** Mentor, expert modeler
 +
 +
* Ed Davisson
 +
** brlcad-devel mailing list
 +
** Part-time mentor, Math guru extraordinaire
 +
 +
* Keith Bowman
 +
** brlcad-devel mailing list
 +
** Part-time mentor, core dev, NURBS guru
 +
 +
* Tom Browder
 +
** brlcad-devel maling list
 +
** Part-time mentor, analysis, code support
 +
 +
* Richard Weiss
 +
** brlcad-devel mailing list
 +
** Part-time mentor, NMG info, code support

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