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author | Kévin Dietrich <kevin.dietrich@mailoo.org> | 2021-12-27 18:34:47 +0300 |
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committer | Kévin Dietrich <kevin.dietrich@mailoo.org> | 2021-12-27 18:35:54 +0300 |
commit | eed45d2a239a2a18a2420ba15dfb55e0f8dc5630 (patch) | |
tree | aa55ce966caa8e28db4853d7d755003ed249805b /source/blender/gpu/GPU_index_buffer.h | |
parent | 31e120ef4997583332aa9b5af93521e7e666e9f3 (diff) |
OpenSubDiv: add support for an OpenGL evaluator
This evaluator is used in order to evaluate subdivision at render time, allowing for
faster renders of meshes with a subdivision surface modifier placed at the last
position in the modifier list.
When evaluating the subsurf modifier, we detect whether we can delegate evaluation
to the draw code. If so, the subdivision is first evaluated on the GPU using our own
custom evaluator (only the coarse data needs to be initially sent to the GPU), then,
buffers for the final `MeshBufferCache` are filled on the GPU using a set of
compute shaders. However, some buffers are still filled on the CPU side, if doing so
on the GPU is impractical (e.g. the line adjacency buffer used for x-ray, whose
logic is hardly GPU compatible).
This is done at the mesh buffer extraction level so that the result can be readily used
in the various OpenGL engines, without having to write custom geometry or tesselation
shaders.
We use our own subdivision evaluation shaders, instead of OpenSubDiv's vanilla one, in
order to control the data layout, and interpolation. For example, we store vertex colors
as compressed 16-bit integers, while OpenSubDiv's default evaluator only work for float
types.
In order to still access the modified geometry on the CPU side, for use in modifiers
or transform operators, a dedicated wrapper type is added `MESH_WRAPPER_TYPE_SUBD`.
Subdivision will be lazily evaluated via `BKE_object_get_evaluated_mesh` which will
create such a wrapper if possible. If the final subdivision surface is not needed on
the CPU side, `BKE_object_get_evaluated_mesh_no_subsurf` should be used.
Enabling or disabling GPU subdivision can be done through the user preferences (under
Viewport -> Subdivision).
See patch description for benchmarks.
Reviewed By: campbellbarton, jbakker, fclem, brecht, #eevee_viewport
Differential Revision: https://developer.blender.org/D12406
Diffstat (limited to 'source/blender/gpu/GPU_index_buffer.h')
-rw-r--r-- | source/blender/gpu/GPU_index_buffer.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/source/blender/gpu/GPU_index_buffer.h b/source/blender/gpu/GPU_index_buffer.h index e4f1709173e..0f83e590597 100644 --- a/source/blender/gpu/GPU_index_buffer.h +++ b/source/blender/gpu/GPU_index_buffer.h @@ -53,6 +53,8 @@ void GPU_indexbuf_init_ex(GPUIndexBufBuilder *, GPUPrimType, uint index_len, uin void GPU_indexbuf_init(GPUIndexBufBuilder *, GPUPrimType, uint prim_len, uint vertex_len); GPUIndexBuf *GPU_indexbuf_build_on_device(uint index_len); +void GPU_indexbuf_init_build_on_device(GPUIndexBuf *elem, uint index_len); + /* * Thread safe. * @@ -82,6 +84,16 @@ void GPU_indexbuf_build_in_place(GPUIndexBufBuilder *, GPUIndexBuf *); void GPU_indexbuf_bind_as_ssbo(GPUIndexBuf *elem, int binding); +/* Upload data to the GPU (if not built on the device) and bind the buffer to its default target. + */ +void GPU_indexbuf_use(GPUIndexBuf *elem); + +/* Partially update the GPUIndexBuf which was already sent to the device, or built directly on the + * device. The data needs to be compatible with potential compression applied to the original + * indices when the index buffer was built, i.e., if the data was compressed to use shorts instead + * of ints, shorts should passed here. */ +void GPU_indexbuf_update_sub(GPUIndexBuf *elem, uint start, uint len, const void *data); + /* Create a sub-range of an existing index-buffer. */ GPUIndexBuf *GPU_indexbuf_create_subrange(GPUIndexBuf *elem_src, uint start, uint length); void GPU_indexbuf_create_subrange_in_place(GPUIndexBuf *elem, |