Updated the Gregory patch tessellation shaders to account for
transition edges.
Changed the implementation of OsdGetTessParameterizationTriangle()
to take the input parametric location as a 3-component value. This
allows the edge parameterization to be more numerically robust and
consistent.
Also, corrected some minor discrepancies between the various
tessellation shader configurations.
- replaced use of "LimitPoints" functions in all patch shaders
- removed the unreleased "LimitPointsTriangle" functions
- added internal tess functions for processing patch boundaries
- updated Bezier quad and tri tess evaluation to use boundary functions
- updated sizes for the Box-spline triangle shader to generate 15 points
- updated conversion of Box-spline from hybrid Bezier to fully quartic
- added resolution of degenerate normal to Bezier triangle evaluation
- updated hybrid Gregory triangle conversion to quartic Bezier
- updated adaptive tessellation of Bezier triangle for quartic boundaries
- Added GLSL patch shaders for BoxSplineTriangle and GregoryTriangle
patches. These both convert to a hybrid Bezier patch for drawing
similar to the basis conversion done for quad patches.
- Added evaluation of hybrid Bezier triangle patches and
GregoryTriangle patches to the common shader source.
- Added OsdGetPatchIsTriangleRotated() to detect rotated triangles.
- Added OsdInterpolatePatchCoordTriangle() for eval of triangle patches.
- Added boundary point extrapolation for BoxSplineTriangle patches.
- Fixed boundary point extrapolation for unisolated BSpline patches.
- Added tess factor and tess evaluation location computation for
triangle patches.
- Limit surface edge mid points for both quad and triangle patches
are now computed directly.