This commit should suffice to make the shader API agnostic now (given that
all users of it use the GPU API).
This makes the shaders not trigger a false positive error anymore since
the binding slots are now garanteed by the backend and not changed at
after compilation.
This also bundles all uniforms into UBOs. Making them extendable without
limitations of push constants. The generated uniforms from OCIO are not
densely packed in the UBO to avoid complexity. Another approach would be to
use GPU_uniformbuf_create_from_list but this requires converting uniforms
to GPUInputs which is too complex for what it is.
Reviewed by: brecht, jbakker
Differential Revision: https://developer.blender.org/D14123
This uses a light parser / string modification pass to convert
C++ enum declaration syntax to GLSL compatible one.
GLSL having no support for enums, we are forced to convert the
enum values to a series of constant uints.
The parser (not really one by the way), being stupidly simple,
will not change anything to the values and thus make some C++
syntax (like omitting the values) not work.
The string replacement happens on all GLSL files on startup.
I did not measure significant changes in blender startup speed.
There is plans to do all of this at compile time.
We limit the scope of the search to `.h` and `.hh` files to prevent
confusing syntax in `.glsl` files.
There is basic error reporting with file, line and char logging
for easy debuggabiliy.
The requirements to use this enum sharing system are already listed in
`gpu_shader_shared_utils.h` and repeated on top of the preprocessor
function.
This is a first part of the Shader Create Info system could be.
A shader create info provides a way to define shader structure, resources
and interfaces. This makes for a quick way to provide backend agnostic
binding informations while also making shader variations easy to declare.
- Clear source input (only one file). Cleans up the GPU api since we can create a
shader from one descriptor
- Resources and interfaces are generated by the backend (much simpler than parsing).
- Bindings are explicit from position in the array.
- GPUShaderInterface becomes a trivial translation of enums and string copy.
- No external dependency to third party lib.
- Cleaner code, less fragmentation of resources in several libs.
- Easy to modify / extend at runtime.
- no parser involve, very easy to code.
- Does not hold any data, can be static and kept on disc.
- Could hold precompiled bytecode for static shaders.
This also includes a new global dependency system.
GLSL shaders can include other sources by using #pragma BLENDER_REQUIRE(...).
This patch already migrated several builtin shaders. Other shaders should be migrated
one at a time, and could be done inside master.
There is a new compile directive `WITH_GPU_SHADER_BUILDER` this is an optional
directive for linting shaders to increase turn around time.
What is remaining:
- pyGPU API {T94975}
- Migration of other shaders. This could be a community effort.
Reviewed By: jbakker
Maniphest Tasks: T94975
Differential Revision: https://developer.blender.org/D13360
