* The CATMARK_QUAD_FACE_VERTEX kernel calculates the face-vertex for a quadrilateral face. It applies to every face after the first subdivision step, and may be applied for the first subdivision step of a quadrilateral coarse mesh.
* The CATMARK_TRI_QUAD_FACE_VERTEX kernel calculates the face-vertex for a triangle or quadrilateral face. It may be applied for the first subdivision step of a coarse mesh composed of triangles and/or quadrilaterals.
* Both kernels calculate each face-vertex using four vertex indices (triangles are specified by repeating the third index). Therefore neither kernel uses the F_ITa codex table, and instead the first vertex offset in the F_IT index table is stored in the FarKernelBatch's table offset.
All kernels take offset/length/stride to apply subdivision partially in each vertex elements.
Also the offset can be used for client-based VBO aggregation, without modifying index buffers.
This is useful for topology sharing, in conjunction with glDrawElementsBaseVertex etc.
However, gregory patch shader fetches vertex buffer via texture buffer, which index should also
be offsetted too. Although gl_BaseVertexARB extension should be able to do that job, it's a
relatively new extension. So we use OsdBaseVertex() call to mitigate the compatibility
issue as clients can provide it in their way at least for the time being.
Moved transient states (current vertex buffer etc) to controller.
ComputeContext becomes constant so that it's well suited for coarse-grain
parallelism on cpu. The prims sharing same topology (ComputeContext) can
be refined simultaneously by having mutiple compute controllers.
Client facing API doesn't change.
* replace void* of all kernel applications with CONTEXT template parameter.
It eliminates many static_casts from void* for both far and osd classes.
* move the big switch-cases of far default kernel launches out of Refine so
that osd controllers can arbitrary mix default kernels and custom kernels.
* change FarKernelBatch::kernelType from enum to int, clients can add
custom kernel types.
* remove a back-pointer to farmesh from subdivision table.
* untemplate all subdivision table classes and template their compute methods
instead. Those methods take a typed vertex storage.
* remove an unused argument FarMesh from the constructor of subdivision
table factories.
New text:
Copyright 2013 Pixar
Licensed under the Apache License, Version 2.0 (the "Apache License")
with the following modification; you may not use this file except in
compliance with the Apache License and the following modification to it:
Section 6. Trademarks. is deleted and replaced with:
6. Trademarks. This License does not grant permission to use the trade
names, trademarks, service marks, or product names of the Licensor
and its affiliates, except as required to comply with Section 4(c) of
the License and to reproduce the content of the NOTICE file.
You may obtain a copy of the Apache License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the Apache License with the above modification is
distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied. See the Apache License for the specific
language governing permissions and limitations under the Apache License.
2 client APIs are changed.
- VertexBuffer::UpdateData() takes start vertex offset
- ComputeController::Refine() takes FarKernelBatchVector
Also, ComputeContext no longer holds farmesh.
Client can free farmesh after OsdComputeContext is created.
(but still need FarKernelBatchVector to apply subdivision kernels)
- [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...
