This loosens the current implementation a bit to only force optimal
display when editing on cage. It used to be any editing mode.
Brings GPU based subdivision closer to the CPU version.
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
Addendum to previous fix, which was for point selection, this fixes the
face selection mode. The issue is caused by wrong flags used for paint
mode (the edit mode flag was always used). Also add back flag which was
accidentally removed in 16f5d51109.
Instancing with geometry nodes uses just the evaluated Mesh, and ignores the
Object that it came from. That meant that it would try to look up the subsurf
modifier on the instancer object which does not have the subsurf modifier.
Instead of storing a session UUID and looking up the modifier data, store a
point to the subsurf modifier runtime data. Unlike the modifier data, this
runtime data is preserved across depsgraph CoW. It must be for the subdiv
descriptor contained in it to stay valid along with the draw cache.
As a bonus, this moves various Mesh_Runtime variables into the subsurf runtime
data, reducing memory usage for meshes not using subdivision surfaces.
Also fixes T98693, issues with subdivision level >= 8 due to integer overflow.
Differential Revision: https://developer.blender.org/D15184
The normals flags were not setup properly which made normals for all
elements (vertices, faces) to be drawn when using the normals overlay.
Also remove usage of uints for the flag in the APIs.
After this commit, all mesh data extraction and drawing code is in C++,
including headers, making it possible to use improved types for future
performance improvements and simplifications.
The only non-trivial changes are in `draw_cache_impl_mesh.cc`,
where use of certain features and macros in C necessitated larger
changes.
Differential Revision: https://developer.blender.org/D15088
Although reusing the same patch coordinate for all corner pointing the
same vertex works for interpolation vertices, it does work for
interpolation face varying attributes. So we need to keep the original
patch coordinates around for face varying interpolation. This was caused
by the previous fix (a5dcae0c64).
Issues stems from the mesh not being watertight. This was caused by
floating point precision issues when evaluating patch coordinates at
patch boundaries (loops/corners in different patches pointing to the same
vertex). To fix this we ensure that all loops pointing to the same vertex
share the same patch coordinate. This keeps code simple, and does not
require to track precision issues in floating point math all over the
place.
Faces, edges, and vertices are still shown when GPU subdivision is
actived. This is because the related edit mode flags were ignored by the
subdivision code.
The flags are now passed to the various compute shaders mostly as part of
the extra coarse data, also used for e.g. selection. For loose edges, a
temporary buffer is created when extracting them. Loose vertices are
already taken into account as it reuses the routines for coarse mesh
extraction, although `MeshRenderData.use_hide` was not initialized,
which is fixed now.
This uses the recently introduced evaluator's vertex
data to smoothly interpolate original coordinates instead
of using linear interpolation.
The orcos are interpolated at the same time as positions
and as such, the specific subdivision routine for the
orco extractor has been removed. The patch evaluation
shader uses a definition to enable code specific to
orco evaluation.
Since the orco layer may not have been requested on first
render, and since orco data is now stored in the OpenSubDiv
evaluator, the evaluator needs to be recreated if an
orco layer is suddenly available. For this, a callback
to check if the evaluator has the data was added. This is
added to the evaluator as the `Subdiv` cache stored in the
modifier is invalidated less often than the Mesh batch cache
and so leads to fewer evaluator recreations.
Differential Revision: https://developer.blender.org/D14999
Knowing when layers are retrieved for write access will be essential
when adding proper copy-on-write support. This commit makes that
clearer by adding `const` where the retrieved data is not modified.
Ref T95842
The mesh drawing code used a different mesh to check whether or not to
draw face dots and to actually retrieve them. The fix is moving the
responsibility of determining whether to use subsurf face dots to the
creation of `MeshRenderData` where the mesh used for drawing is
known, rather than doing it at a higher level.
Differential Revision: https://developer.blender.org/D14855
The mesh drawing code used a different mesh to check whether or not to
draw face dots and to actually retrieve them. The fix is moving the
responsibility of determining whether to use subsurf face dots to the
creation of `MeshRenderData` where the mesh used for drawing is
known, rather than doing it at a higher level.
Differential Revision: https://developer.blender.org/D14855
The coarse polygon count was set to the one of the BMesh instead of
the the one of the mesh used for subdivision, which caused the
compute shaders to output wrong data.
The crash is caused as the data for the UV editor is requested before
the data for the mesh as a separate draw update. Since building the UV
stretch angle buffer requires the position buffer, the latter is not
created yet in this case.
To fix this, create a local position buffer from the subdivision data. An
alternate fix was considered to remove the dependency on the position
buffer by interpolating on the GPU the coarse stretch angle buffer but
this did work. Maybe this will be revisited.
Simple port with a few cosmetic changes:
- Attribute named "color" for indices VBO is now called "index"
- The indices VBO is now composed of `int`s instead of `uint`s (this simplifies the source)
Differential Revision: https://developer.blender.org/D14800
The subdivision is always recomputed on the CPU when displaying stats
if the mesh is animated which leads to bad performance.
This caches the subdivision topology counters from the draw code in the
mesh runtime and uses them for the viewport statistics.
Differential Revision: https://developer.blender.org/D14774
When more than one, consecutive, subdivision modifier is used on a Mesh,
the last subsurf modifier is used for GPU subdivision even though it
might be disabled. This is because retrieving the last subsurf modifier
in the draw code did not check whether the modifier was disabled or not.
To fix this, the session UUID of the modifier which delegated evaluation
to the GPU code is cached and used in the draw to select the right subsurf
modifier.
Differential Revision: https://developer.blender.org/D14488
edges
When wireframe mode is turned on, the subdivision edges not originating
from coarse edges were also drawn as regular edges, which would confuse
users trying to select them. These should not be drawn in edit mode,
only in object mode when optimal display is turned off (matching the CPU
subdivision case).
`GPU_shader_get_uniform_block` is marked as deprecated and the value
returned does not match what `GPU_uniformbuf_bind` expects.
Also, small typo fix in python error message.
Differential Revision: https://developer.blender.org/D14638
The lines paint mask IBO extraction was not implemented for GPU subdivision.
For it to work, we also now need to preserve the subdivision loop to
subdivision edge map, which until now was overwritten to store coarse edges
(the map to coarse edges is still preserved).
Also the paint flag stored in the 4th dimension of the loop normal buffer
was not properly set for flat shaded faces, leading to other kind of
artefacts and render issues.
Some old platforms and drivers have limited amount of SSBO binding per
compute shader. This disables GPU subdivision if we cannot possibly
bind all required buffers within this limit.
For now the maximum number of buffers used by the GPU code is hardcoded,
but will be programmatically detected when shader creation is automated.
Ref D14337
There are two issues revealed in the bug report:
- the GPU subdivision does not support meshes with only loose geometry
- the loose geometry is not subdivided
For the first case, checks are added to ensure we still fill the
buffers with loose geometry even if no polygons are present.
For the second case, this adds
`BKE_subdiv_mesh_interpolate_position_on_edge` which encapsulates the
loose vertex interpolation mechanism previously found in
`subdiv_mesh_vertex_of_loose_edge`.
The subdivided loose geometry is stored in a new specific data structure
`DRWSubdivLooseGeom` so as to not pollute `MeshExtractLooseGeom`. These
structures store the corresponding coarse element data, which will be
used for filling GPU buffers appropriately.
Differential Revision: https://developer.blender.org/D14171
A simple case of missing the tangent VBO. The tangents are computed from
the coarse mesh, and interpolated on the GPU for the final mesh. Code for
initializing the tangents, and the vertex format for the VBO was
factored out of the coarse extraction routine, to be shared with the
subdivision routine.
Reuse the same vertex normals calculation as for the GPU code, by
weighing each vertex normals by the angle of the edges incident to the
vertex on the face.
Additionally, remove limit normals, as the CPU code does not use them
either, and would also cause different shading issues when limit surface
is used.
Fixes T95242: shade smooth artifacts with edge crease and limit surface
Fixes T94919: subdivision, different shading between CPU and GPU
