openSubdiv_init() would detect available evaluators before any OpenGL context
exists, causing a crash with libepoxy. This test however is redundant as we
already check the requirements on the Blender side through the GPU API.
To simplify things, completely remove the device detection in the opensubdiv
module and reduce the evaluators to just CPU and GPU. The plan here is to move
to the GPU module abstraction over OpenGL/Metal/Vulkan and so all these
different backends no longer make sense.
This also removes the user preference for OpenSubdiv compute device, which was
not used for the new GPU subdivision implementation.
Ref D15291
Differential Revision: https://developer.blender.org/D15470
Main goal is to make API simpler to follow (at least ion terms what
is defined/declared where, as opposite of handful big headers which
includes all the declarations), and also avoid a big set of long and
obscure functions.
Now C-API files are split into smaller ones, following OpenSubdiv
behavior more closely, and also function pointers in structures
used a lot more, which shortens functions names,
UV integration part in GL Mesh is mainly stripped away, it needs
to be done differently. On a related topic, UV coordinates API in
converter needs to be removed as well, we do not need coordinates,
only island connectivity information there.
Additional changes:
- Varying interpolation in evaluator API are temporarily disabled,
need to extend API somewhere (probably, evaluator's API) to inform
layout information of vertex data (whether it contains varying
data, width, stride and such).
- Evaluator now can interpolate face-varying data.
Only works for adaptive refiner, since some issues in OpenSubdiv
itself.
Planned changes:
- Remove uv coordinates from TopologyConverter.
- Support evaluation of patches (as opposite to individual coordinates
as it happens currently).
- Support more flexible layout of varying and face-varying data.
It is stupid to assume varying is 3 floats and face-varying 2 floats.
- Support of second order derivatives.
- Everything else what i'm missing in this list.
- Made OpenSubdiv_GLMesh private
Previously, it was still accessible via C-API from C++ code.
- Don't implicitly refine evaluator when updating coarse positions,
now there is an explicit call to do this.
Allows to first apply all changes to the coarse mesh and then
refine once.
- Added coarse positions update from a continuous buffer with given
starts offset and stride.
Allows to update coarse positions directly from MVert array.
- Refiner is no longer freed when CPU evaluator is created.
Allows to re-use refiner for multiple purposes.
A bit work in progress, currently the following limitations:
- Texture shading only, Material shading will come later
- No UVs subdivision yet
- Always uses active UV and currently changing active UV will
not properly update the viewport.
Well, need to start somewhere :)
Use new GPU_legacy_support() function.
Determine GLSL version once instead of per shader.
For Texture Buffers, allow ARB or EXT version of the extension. Either
one will do.
It's hopefully no longer needed, at least not needed for as long as
single ptex face corresponds to a single patch which should be always
correct for uniform subdivisions as far as i know.
Implementation is less optimal compared to non-opensubdiv drawing but
it is now as good as we can do it without affecting on how patches are
being created by OpenSubdiv.
This includes C-API bindings in intern/opensubdiv and CMAke module
which finds the OpenSubdiv library. This filea are not in use so
far, making it a separate commit to make actual integration commit
more clear.