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
Getting there, this code is being tested with Presto deformers and is working well. Valgrind reports no memory errors with the simple projectTest test harness.
set HBR_ADAPTIVE before including hbr code. Also use an ifndef in
far/meshFactory.h so that code can be included where someone else has
already defined HBR_ADAPTIVE.
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
For face-varying interpolation, sharpness should be interpreted as an
infintely sharp boundary. Hbr implements this correctly for vertex
sharpness, but inconsistently for edge sharpness: both the fvarbits
cache and methods that gather face-varying sharpness need to be corrected.
fixes#231
