GPUShader: Improve builtins support in GPUShaderCreateInfo

- Scan all static shaders for builtins on startup.
- Add possibility to manually add builtins.
- `ShaderCreateInfo.builtins_` contain builtins from all stages.

1 files changed, 13 insertions, 0 deletions

diff --git a/source/blender/gpu/intern/gpu_shader_create_info.hh b/source/blender/gpu/intern/gpu_shader_create_info.hh
index 63c6e94f4c8..e68f9929591 100644
--- a/source/blender/gpu/intern/gpu_shader_create_info.hh
+++ b/source/blender/gpu/intern/gpu_shader_create_info.hh
@@ -63,6 +63,7 @@ enum class Type {
 };
 
 enum class BuiltinBits {
+  NONE = 0,
   /**
    * Allow getting barycentric coordinates inside the fragment shader.
    * \note Emulated on OpenGL.
@@ -72,6 +73,10 @@ enum class BuiltinBits {
   FRONT_FACING = (1 << 4),
   GLOBAL_INVOCATION_ID = (1 << 5),
   INSTANCE_ID = (1 << 6),
+  /**
+   * Allow setting the target layer when the output is a layered framebuffer.
+   * \note Emulated through geometry shader on older hardware.
+   */
   LAYER = (1 << 7),
   LOCAL_INVOCATION_ID = (1 << 8),
   LOCAL_INVOCATION_INDEX = (1 << 9),
@@ -226,6 +231,8 @@ struct ShaderCreateInfo {
    * Only for names used by gpu::ShaderInterface.
    */
   size_t interface_names_size_ = 0;
+  /** Manually set builtins. */
+  BuiltinBits builtins_ = BuiltinBits::NONE;
 
   struct VertIn {
     int index;
@@ -538,6 +545,12 @@ struct ShaderCreateInfo {
     return *(Self *)this;
   }
 
+  Self &builtins(BuiltinBits builtin)
+  {
+    builtins_ |= builtin;
+    return *(Self *)this;
+  }
+
   /** \} */
 
   /* -------------------------------------------------------------------- */