Difference between revisions of "NURBS TODO"

From BRL-CAD
(initial stab at remaining NURBS tasks)
 
(several items completed including V&V and prep caching)
 
(9 intermediate revisions by 3 users not shown)
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* Optimize BREP/NURBS ray tracing
+
= Profile BREP/NURBS ray tracing=
−
** Benefit: faster ray tracing runtime
+
* Benefit: better ray tracing runtime understanding, supports test case development
−
* Optimize BREP/NURBS prep
+
* Time Estimate: 2 days
−
** Benefit: faster ray tracing runtime, user requested.
+
* References:
−
* Implement conversion of implicit primitives to BREP/NURBS primitives.
+
** src/libbrep
−
** Partially complete, primitives are fixed at origin, some primitives unimplemented.
+
** src/librt/primitives/brep
−
** Benefit: partial requirement for interactive visualization of implicit CSG geometry in OpenGL.
+
** src/librt/opennurbs_ext.*
−
* Implement conversion of BREP/NURBS to NMG.
+
 
−
** Benefit: partial requirement for export and interactive visualization of BREP/NURBS in OpenGL.
+
= Optimize BREP/NURBS prep=
−
* Identify useful concepts implemented in the old BSPLINE/NURBS code that are not present in openNURBS.
+
Perform limited tree splitting during prep, split dynamically during ray trace, store lock-free.
−
** Benefit: code reuse, potentially very useful functionality.
+
* Benefit: faster ray tracing throughput, user requested, user visible
−
* Port any useful BSPLINE/NURBS code to openNURBS data structures and routines.
+
* Time Estimate: 1 week
−
** Benefit: code reduction, allows the old BSPLINE/NURBS code to be removed after functionality is migrated.
+
* References:
−
* Implement boolean evaluation of BREP/NURBS surfaces.
+
** src/libbrep
−
** Benefit: partial requirement for interactive visualization of BREP/NURBS in OpenGL.
+
** src/librt/primitives/brep/brep.cpp:rt_brep_prep()
−
* Implement plate mode BREP/NURBS objects.
+
** src/librt/opennurbs_ext.*
−
** Similar, if not identical, to plate mode BoTs, 'brep' objects need the ability to have a thickness described so you could automatically handle non-solid NURBS and sheet-metal style geometry without requiring surface solidity.
+
 
−
** Benefit: allows for import and visualization of BREP/NURBS surfaces that are not solid.
+
= Convert existing entities to NURBS=
−
* Develop test scripts for comparing conversion of implicit CSG to BREP/NURBS CSG
+
Implement hooks to describe entities in BREP/NURBS form. Partially complete for most, but some complex entities remain unimplemented.
−
** Benefit: provides validation and verification via ray tracing.
+
* Benefit: partial requirement for interactive visualization of implicit CSG geometry in OpenGL
−
* Document the new BREP/NURBS primitive.
+
* Time Estimate: 2 days per entity
−
** Benefit: provides user documentation explaining capabilities, limitations, and benefits.
+
* References:
−
* Implement data cache objects.
+
** src/librt/primitives/${PRIM}/${PRIM}_brep.cpp
−
** Create new LIBRT API routines for storing cache data in a v5 container. This would amount to storing binary data into a 'binunif' object marked as hidden with attributes for date/time stamping and MD5 or SHA256 checksumming.
+
 
−
** Benefit: faster ray tracing runtime, applicable to other primitives (NMG, BoT).
+
= BREP/NURBS-to-NMG=
−
* Cache BREP/NURBS prep results to a specified cache file.
+
Implement conversion of BREP/NURBS to NMG.
−
** Benefit: faster ray tracing runtime for BREP/NURBS, user requested.
+
* Benefit: requirement for polygonal export, partial requirement for OpenGL visualization, user visible
−
* Improve BREP/NURBS wireframe.
+
* Time Estimate: 2 days
−
** Investigate using knots on subcurves.
+
* References:
−
** Benefit: faster wireframe, more detailed close wireframes.
+
** src/librt/primitives/brep/brep.cpp:rt_brep_tess()
−
* BREP/NURBS source code cleanup.
+
 
−
** Consolidate Owens and Reeves approaches to ray intersection.
+
= Old BSPLINE/NURBS review=
−
** Benefit: improved code maintainability.
+
Identify useful concepts implemented in the old BSPLINE/NURBS code that are not present in openNURBS.
−
* Implement an rt_heal(rt_db_internal *dbi); routine.
+
* Benefit: code reuse, potentially very useful functionality.
−
** The routine tightens up trimming curves and edge/vertex pairings so that they align perfectly while still preserving the topological structure.
+
* Time Estimate: 1 day
−
* Write an report on using NURBS for analysis purposes.
+
* References:
−
* Perform analytic comparison of BREP/NURBS and BoT geometry
+
** src/librt/primitives/bspline/*
−
* Perform analytic comparison of BREP/NURBS CSG and implicit CSG geometry
+
 
−
* Implement support for rotation, scaling, and translations.
+
= BSPLINE/NURBS reuse=
 +
Port any useful BSPLINE/NURBS code to openNURBS data structures and routines.
 +
* Benefit: code reduction, allows the old BSPLINE/NURBS code to be removed after functionality is migrated.
 +
* Time Estimate: 2 days
 +
* References:
 +
** src/librt/primitives/bspline/*
 +
** src/librt/primitives/brep/*
 +
 
 +
=BREP/NURBS CSG evaluation=
 +
Implement boolean evaluation of BREP/NURBS surfaces.
 +
* Benefit: partial requirement for interactive visualization of BREP/NURBS in OpenGL.
 +
* Time Estimate: 2 years (for 100% robustness)
 +
* References:
 +
** ESOLID: http://research.cs.tamu.edu/keyser/geom/esolid/
 +
** http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.119.4341&rep=rep1&type=pdf
 +
** http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.117.8700&rep=rep1&type=pdf
 +
** http://www.springerlink.com/content/x3665206243u20x8/
 +
** http://193.170.37.128/projects/basic/cgal/workdone/nurbs-97-30.ps.gz
 +
** http://mae.ucdavis.edu/~farouki/foils.pdf
 +
** http://portal.acm.org/citation.cfm?id=36714
 +
** ftp://ftp.cs.unc.edu/pub/users/manocha/PAPERS/INTERSECT/IJCGA.pdf
 +
** http://portal.acm.org/citation.cfm?id=237751
 +
 
 +
=Implicit CSG to BREP/NURBS CSG test scripts=
 +
Develop test scripts for comparing conversion of implicit CSG to BREP/NURBS CSG
 +
* Benefit: provides validation and verification via ray tracing.
 +
* Time Estimate: < 1 day
 +
* References:
 +
** regress/*.sh
 +
** sh/*.sh
 +
 
 +
=BREP/NURBS documentation=
 +
Document the new BREP/NURBS primitive (user overviewdocumentation: how to import, use, export, limitations).
 +
* Benefit: provides user documentation explaining capabilities, limitations, and benefits; user visible
 +
* Time Estimate: 3 days
 +
* References:
 +
** doc/docbook/articles
 +
 
 +
=BREP/NURBS wireframe=
 +
Improve BREP/NURBS wireframe. Investigate using knots on subcurves.
 +
* Benefit: faster wireframe; LOD wireframes: more detailed close-up wireframes, less detailed far-away wireframes (LOD); user visible
 +
* Time Estimate: 2 days
 +
* References:
 +
** http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.142.3042&rep=rep1&type=pdf
 +
** http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.70.6138&rep=rep1&type=pdf
 +
** http://www.springerlink.com/content/k7543860533338nu/
 +
** http://wscg.zcu.cz/wscg2003/Papers_2003/H19.pdf
 +
** http://cg.cs.uni-bonn.de/aigaion2root/attachments/kahlesz-2002-multiresolution.pdf
 +
** http://www.cs.cityu.edu.hk/~rynson/papers/vrst03.pdf
 +
** http://www.flipcode.com/archives/NURBS_Curves_Surfaces.shtml
 +
 
 +
= BREP/NURBS source code cleanup=
 +
Consolidate Owens and Reeves approaches to ray intersection.
 +
* Benefit: improved code maintainability, complexity reduction
 +
* Time Estimate: 2 days
 +
* References:
 +
** http://www.cs.utah.edu/~shirley/papers/raynurbs.pdf
 +
 
 +
= BREP/NURBS healing=
 +
Implement an rt_heal(rt_db_internal *dbi); routine. The routine tightens up trimming curves and edge/vertex pairings so that they align perfectly while still preserving the topological structure.
 +
* Benefit: more robust evaluation for improved (more stable & consistent) raytracing, import, export; routine interface later applicable to NMG/BoT too
 +
* Time Estimate: 3 days
 +
* References:
 +
** src/librt/primitives/brep

Latest revision as of 16:55, 26 August 2016

Profile BREP/NURBS ray tracing[edit]

  • Benefit: better ray tracing runtime understanding, supports test case development
  • Time Estimate: 2 days
  • References:
    • src/libbrep
    • src/librt/primitives/brep
    • src/librt/opennurbs_ext.*

Optimize BREP/NURBS prep[edit]

Perform limited tree splitting during prep, split dynamically during ray trace, store lock-free.

  • Benefit: faster ray tracing throughput, user requested, user visible
  • Time Estimate: 1 week
  • References:
    • src/libbrep
    • src/librt/primitives/brep/brep.cpp:rt_brep_prep()
    • src/librt/opennurbs_ext.*

Convert existing entities to NURBS[edit]

Implement hooks to describe entities in BREP/NURBS form. Partially complete for most, but some complex entities remain unimplemented.

  • Benefit: partial requirement for interactive visualization of implicit CSG geometry in OpenGL
  • Time Estimate: 2 days per entity
  • References:
    • src/librt/primitives/${PRIM}/${PRIM}_brep.cpp

BREP/NURBS-to-NMG[edit]

Implement conversion of BREP/NURBS to NMG.

  • Benefit: requirement for polygonal export, partial requirement for OpenGL visualization, user visible
  • Time Estimate: 2 days
  • References:
    • src/librt/primitives/brep/brep.cpp:rt_brep_tess()

Old BSPLINE/NURBS review[edit]

Identify useful concepts implemented in the old BSPLINE/NURBS code that are not present in openNURBS.

  • Benefit: code reuse, potentially very useful functionality.
  • Time Estimate: 1 day
  • References:
    • src/librt/primitives/bspline/*

BSPLINE/NURBS reuse[edit]

Port any useful BSPLINE/NURBS code to openNURBS data structures and routines.

  • Benefit: code reduction, allows the old BSPLINE/NURBS code to be removed after functionality is migrated.
  • Time Estimate: 2 days
  • References:
    • src/librt/primitives/bspline/*
    • src/librt/primitives/brep/*

BREP/NURBS CSG evaluation[edit]

Implement boolean evaluation of BREP/NURBS surfaces.

Implicit CSG to BREP/NURBS CSG test scripts[edit]

Develop test scripts for comparing conversion of implicit CSG to BREP/NURBS CSG

  • Benefit: provides validation and verification via ray tracing.
  • Time Estimate: < 1 day
  • References:
    • regress/*.sh
    • sh/*.sh

BREP/NURBS documentation[edit]

Document the new BREP/NURBS primitive (user overviewdocumentation: how to import, use, export, limitations).

  • Benefit: provides user documentation explaining capabilities, limitations, and benefits; user visible
  • Time Estimate: 3 days
  • References:
    • doc/docbook/articles

BREP/NURBS wireframe[edit]

Improve BREP/NURBS wireframe. Investigate using knots on subcurves.

BREP/NURBS source code cleanup[edit]

Consolidate Owens and Reeves approaches to ray intersection.

BREP/NURBS healing[edit]

Implement an rt_heal(rt_db_internal *dbi); routine. The routine tightens up trimming curves and edge/vertex pairings so that they align perfectly while still preserving the topological structure.

  • Benefit: more robust evaluation for improved (more stable & consistent) raytracing, import, export; routine interface later applicable to NMG/BoT too
  • Time Estimate: 3 days
  • References:
    • src/librt/primitives/brep
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