GPencil 3D stroke rendering uses a geometry shader.
This is unsupported by the Metal backend, so implement
fix for this failing compilation by shifting geometry shader
logic into the Vertex shader for Metal backend.
Authored by Apple: Michael Parkin-White
Ref #96261
Pull Request #105143
Resolves issue with nearest filtering on UI Icons. Note that as
Metal does not support LOD bias as a parameter on a sampler
object, the original code has been modified to perform LOD
biasing at the shader level.
As GPU_SAMPLER_ICON is not widely used, it is more
efficient to apply directly to the affected shaders, rather
than workaround passing in the sampler LOD bias as a
separate value e.g. uniform or push constant.
Original PR feedback addressed to also refactor ICON
shaders to use consistent style for single and multi
Icon rendering.
Authored by Apple: Michael Parkin-White
Ref #96261
Pull Request #105145
The stoke shader of grease pencil uses a geometry shader stage. Apple
devices don't support shaders with geometry shader stage. In the
OpenGL driver there was a pass-through implemented so it didn't fail.
When using the metal backend this needs to be solved more explicitly.
This change patches the grease pencil shader to support both the
backends supporting a geometry stage and those without.
Fixes#105059
Pull Request #105116
This replaces `GPU_SHADER_3D_POINT_FIXED_SIZE_VARYING_COLOR` by
GPU_SHADER_2D_POINT_UNIFORM_SIZE_UNIFORM_COLOR_OUTLINE_AA`.
None of the usage made sense to not use the AA shader.
Scale the point size to account for the rounded shape.
