shader_recompiler: add gl_Layer translation GS for older hardware

1 files changed, 9 insertions, 0 deletions

diff --git a/src/shader_recompiler/frontend/maxwell/translate_program.h b/src/shader_recompiler/frontend/maxwell/translate_program.h
index 02ede8c9c..497afe7cb 100644
--- a/src/shader_recompiler/frontend/maxwell/translate_program.h
+++ b/src/shader_recompiler/frontend/maxwell/translate_program.h
@@ -25,4 +25,13 @@ namespace Shader::Maxwell {
 
 void ConvertLegacyToGeneric(IR::Program& program, const RuntimeInfo& runtime_info);
 
+// Maxwell v1 and older Nvidia cards don't support setting gl_Layer from non-geometry stages.
+// This creates a workaround by setting the layer as a generic output and creating a
+// passthrough geometry shader that reads the generic and sets the layer.
+[[nodiscard]] IR::Program GenerateGeometryPassthrough(ObjectPool<IR::Inst>& inst_pool,
+                                                      ObjectPool<IR::Block>& block_pool,
+                                                      const HostTranslateInfo& host_info,
+                                                      IR::Program& source_program,
+                                                      Shader::OutputTopology output_topology);
+
 } // namespace Shader::Maxwell