Realtime Compositor: Add needed GPU module changes

This patch implements the necessary changes to the GPU module that are
needed by the realtime compositor.

A new function GPU_material_from_callbacks was added to construct a GPU
material from a number of callbacks. A callback to construct the
material graph by adding and linking the necessary GPU material nodes.
And the existing code generator callback. This essentially allows the
construction of GPU materials independent of node trees and without the
need to do any node tree localization.

A new composite source output to the code generator was added. This
output contains the serialization of nodes that are tagged with
GPU_NODE_TAG_COMPOSITOR, which are the nodes linked to the newly added
composite output links.

Two new GPU uniform setters were added for int2 and matrix3 types.

Shader create info now supports generated compute sources.

Shaders starting with gpu_shader_compositor are now considered part of
the shader library.

Additionally, two fixes were implemented. First, GPU setter node
de-duplication now appropriately increments the reference count of the
references resources. Second, unlinked sockets now get their value from
their associated GPU node stack instead of the socket itself.

Differential Revision: https://developer.blender.org/D14690

Reviewed By: Clement

1 files changed, 14 insertions, 0 deletions

diff --git a/source/blender/gpu/GPU_material.h b/source/blender/gpu/GPU_material.h
index 3ca465fa57a..12a7cf49f9d 100644
--- a/source/blender/gpu/GPU_material.h
+++ b/source/blender/gpu/GPU_material.h
@@ -121,6 +121,7 @@ typedef struct GPUCodegenOutput {
   char *surface;
   char *volume;
   char *thickness;
+  char *composite;
   char *material_functions;
 
   GPUShaderCreateInfo *create_info;
@@ -178,6 +179,8 @@ void GPU_material_output_thickness(GPUMaterial *material, GPUNodeLink *link);
 
 void GPU_material_add_output_link_aov(GPUMaterial *material, GPUNodeLink *link, int hash);
 
+void GPU_material_add_output_link_composite(GPUMaterial *material, GPUNodeLink *link);
+
 /**
  * Wrap a part of the material graph into a function. You need then need to call the function by
  * using something like #GPU_differentiate_float_function.
@@ -218,6 +221,7 @@ GPUMaterial *GPU_material_from_nodetree(struct Scene *scene,
                                         void *thunk);
 
 void GPU_material_compile(GPUMaterial *mat);
+void GPU_material_free_single(GPUMaterial *material);
 void GPU_material_free(struct ListBase *gpumaterial);
 
 void GPU_material_acquire(GPUMaterial *mat);
@@ -319,6 +323,16 @@ struct GHash *GPU_uniform_attr_list_hash_new(const char *info);
 void GPU_uniform_attr_list_copy(GPUUniformAttrList *dest, GPUUniformAttrList *src);
 void GPU_uniform_attr_list_free(GPUUniformAttrList *set);
 
+/* A callback passed to GPU_material_from_callbacks to construct the material graph by adding and
+ * linking the necessary GPU material nodes. */
+typedef void (*ConstructGPUMaterialFn)(void *thunk, GPUMaterial *material);
+
+/* Construct a GPU material from a set of callbacks. See the callback types for more information.
+ * The given thunk will be passed as the first parameter of each callback. */
+GPUMaterial *GPU_material_from_callbacks(ConstructGPUMaterialFn construct_function_cb,
+                                         GPUCodegenCallbackFn generate_code_function_cb,
+                                         void *thunk);
+
 #ifdef __cplusplus
 }
 #endif