The Chaikin crease interpolation mode seems to be broken:
- Catmark / Loop / Bilinear are passing the wrong halfedge vertex to the
SubdivideCreaseWeight function which results in sub-edge crease weights
being swapped
- the loop that iterates over adjacent edges needs to check against both
the original edge and its opposite, otherwise it may be incorrectly
accumulated into summation of these adjacent edges (with a 0.25 weight)
The proposed fix:
- Swaps the Dest/Org vertex passed to the SubdivideCreaseWeight (and
we probably want Julian to confirm that this the correct fix)
- Checks against both the original edge and its opposite in the iteration
over adjacent edges
- Replaces the std::vector based query with an HbrHalfedgeOperator for
better performance (hopefully)
The similar fix to OpenSubdiv been reviewed by Tony DeRose.
Also in the fix:
- fix "obj" tag parsing of the smooth triangle tag that was incorrectly
associated with the crease method (and reporting the wrong errors)
- add regression shapes for both Loop & Catmark schemes to hbr_regression
- add same shapes to the glViewer
- improve hbr_regression output to be more readable
- add command-line argument parsing to hbr_regression
- add functionality to dump an obj file when regression fails for comparison
fixes#235
Also:
- add 2 shape examples with Chaikin rule tag
- add shapes to the glViewer
- add a stub in the documentation
Note: the Chaikin rule currently applied by Hbr appears to be somewhat off...
fixes#236
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that do not have that type of data
- fix some regression shapes that had "empty" uv values
(including some minor topo surgery that luckily appears to not break
regression baselines)
of this quad to be tagged as boundary. These vertices will cause the
feature adaptive pass to generate sub-faces where appropriate, however
the face itself will not be identified as "non-patch", which causes the
FarPatchTables factory to mis-identify it and fall-back on an assert.
This fix flags these particular quad faces in the first adaptive pass.
The particular shape that caused the crash has also been addded to our
regression suite.
fixes#159
- add tag parsing for h-hole in shape_utils
- re-create Renderman's test shape from the documentation (catmark_square_hedit.h)
- fix Hbr to correctly pass the hole tag from parent to child face
- fix FarSubdivisionTables to handle disconnected face-vertices without crashing
fixes#75
while retaining a necessary 1-ring on the inside of a hole edge
- add IsInsideHole() function to HbrHalfEdge
- add HasChild() function to HbrVertex and HbrHalfedge
- add a regression shape with adjacent holes and creases (tests dart, crease & boundaries)
Note : this does not address hierarchical edits inside holes or hole tags in hierarchical edits
fixes#78
- make sure HBR passes down the hole tag to children when subdividing faces
- minor API modification : allow to unset the hole flag on a face
- modify uniform / adaptive FarMeshFactory to be aware of the flag
- make the FarSubdivisionTableFactory assert when finding unconnected HBR vertices (as it should)
* Uniform subdivision :
The refinement scheme only creates faces & vertices necessary
to maintain the one-ring around the edges of a hole, so this solution
is quite efficient.
* Adaptive subdivision :
At the moment we are still performing full topological analysis on holes and
only skipping patches associated to holes. This is sub-optimal in 2 ways :
1. the topological analysis can potentially be cranking on a lot of unnecessary
geometry
2. even though we may not be drawing the patches, the compute stage is still
applying kernels on all the control vertices of these patches.
We will have to revisit feature adaptive subdivision & holes, so keep the issue active.
fixes#78
- [Feature Adaptive GPU Rendering of Catmull-Clark Surfaces](http://research.microsoft.com/en-us/um/people/cloop/tog2012.pdf).
- New API architecture : we are planning to lock on to this new framework as the basis for backward compatibility, which we will enforce from Release 1.0 onward. Subsequent releases of OpenSubdiv should not break client code.
- DirectX 11 support
- and much more...
rules are set to "none" (both in Catmark & Loop)
* Amended shape_utils to always set a default boundary interp. rule
even when no tag was read (ie. don't default to "none")
* Added a regression test for the "dart" shape to test both
"edge only" and "edge corner" boundary interp. rules.
Closes#2.