This patch will use compute shaders to create the VBO for hair.
The previous implementation uses transform feedback.
Timings before: between 0.000069s and 0.000362s.
Timings after: between 0.000032s and 0.000092s.
Speedup isn't noticeable by end-users. The patch is used to test
the new compute shader pipeline and integrate it with the draw
manager. Allowing EEVEE, Workbench and other draw engines to
use compute shaders with the introduction of `DRW_shgroup_call_compute`
and `DRW_shgroup_vertex_buffer`.
Future improvements are possible by generating the index buffer
of hair directly on the GPU.
NOTE: that compute shaders aren't supported by Apple and still use
the transform feedback workaround.
Reviewed By: fclem
Differential Revision: https://developer.blender.org/D11057
This reverts commit 8f9599d17e.
Mac seems to have an error with this change.
```
ERROR: /Users/blender/git/blender-vdev/blender.git/source/blender/draw/intern/draw_hair.c:115:44: error: use of undeclared identifier 'shader_src'
ERROR: /Users/blender/git/blender-vdev/blender.git/source/blender/draw/intern/draw_hair.c:123:13: error: use of undeclared identifier 'shader_src'
ERROR: make[2]: *** [source/blender/draw/CMakeFiles/bf_draw.dir/intern/draw_hair.c.o] Error 1
ERROR: make[1]: *** [source/blender/draw/CMakeFiles/bf_draw.dir/all] Error 2
ERROR: make: *** [all] Error 2
```
This patch will use compute shaders to create the VBO for hair.
The previous implementation uses tranform feedback.
Timings master (transform feedback with GPU_USAGE_STATIC between 0.000069s and 0.000362s
Timings transform feedback with GPU_USAGE_DEVICE_ONLY. between 0.000057s and 0.000122s
Timings compute shader between 0.000032 and 0.000092s
Future improvements:
* Generate hair Index buffer using compute shaders: currently done single threaded on CPU, easy to add as compute shader.
Reviewed By: fclem
Differential Revision: https://developer.blender.org/D11057
This is to modernize the API:
- Add meaningful name to all textures (except DRW textures).
- Remove unused err_out argument: only used for offscreen python.
- Add mipmap count to creation functions for future changes.
- Clarify the data usage in creation functions.
This is a cleanup commit, there is no functional change.
# Conflicts:
# source/blender/gpu/GPU_texture.h
