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
Memory leak is introduced as test cases reinitializes the GPU stack.
Added a call to GPU_backend_exit to fix this.
In GPU_backend_exit the GPU backend was destroyed but the pointer wasn't
reset for reuse. This patch also clears the pointer to be reused.
This makes the GPUContext follow the same naming convention as the rest
of the module.
Also add a static getter for extra bonus style (no need for casts):
- Context::get()
- GLContext::get()
This is part of the Vulkan backend task T68990.
This is mostly a cleanup, however, there is a small change:
We don't use a special Vertex Array binding function for Immediate
anymore and just reuse the one for batches.
This might create a bit more state changes but this could be fixed
easily if it causes perf regression.
# Conflicts:
# source/blender/gpu/intern/gpu_context.cc
This is in preparation of the Framebuffer GL backend.
This is a just changing types and moving some code.
No logic is changed... almost... it just removes the context attach.
i.e: `gpu_context_add/remove_framebuffer()`
This is not needed for now and was even disabled in release.
This is part of T68990.
This changes the drawing paradigm a bit. The VAO configuration is done
JIT-style and depends on context active shader.
This is to allow more flexibility for implementations to do optimization
at lower level.
The vao cache is now its own class to isolate the concept. It is this
class that is reference by the GLContext for ownership of the containing
VAO ids.
This just set a global object responsible for allocating new objects
in a thread safe way without needing any GPUContext bound to this
thread.
This also introduce the GLContext which will contain all the GL related
functions for the current context.
# Conflicts:
# source/blender/gpu/intern/gpu_context.cc
This just set a global object responsible for allocating new objects
in a thread safe way without needing any GPUContext bound to this
thread.
This also introduce the GLContext which will contain all the GL related
functions for the current context.
