[Mesa-dev] [PATCH 12/92] tgsi_from_mesa: add tgsi_get_gl_frag_result_semantic

[Nicolai Hähnle]

From: Nicolai Hähnle <nicolai.haehnle at amd.com>

---
 src/gallium/auxiliary/tgsi/tgsi_from_mesa.c | 35 +++++++++++++++++++++++++++++
 src/gallium/auxiliary/tgsi/tgsi_from_mesa.h |  5 +++++
 2 files changed, 40 insertions(+)

diff --git a/src/gallium/auxiliary/tgsi/tgsi_from_mesa.c b/src/gallium/auxiliary/tgsi/tgsi_from_mesa.c
index 44fae1c..b7a21f2 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_from_mesa.c
+++ b/src/gallium/auxiliary/tgsi/tgsi_from_mesa.c
@@ -141,10 +141,45 @@ tgsi_get_gl_varying_semantic(gl_varying_slot attr,
    case VARYING_SLOT_VAR0:
    default:
       assert(attr >= VARYING_SLOT_VAR0 ||
              (attr >= VARYING_SLOT_TEX0 && attr <= VARYING_SLOT_TEX7));
       *semantic_name = TGSI_SEMANTIC_GENERIC;
       *semantic_index =
          tgsi_get_generic_gl_varying_index(attr, needs_texcoord_semantic);
       break;
    }
 }
+
+/**
+ * Determine the semantic name and index used for the given fragment shader
+ * result.
+ */
+void
+tgsi_get_gl_frag_result_semantic(gl_frag_result frag_result,
+                                 unsigned *semantic_name,
+                                 unsigned *semantic_index)
+{
+   if (frag_result >= FRAG_RESULT_DATA0) {
+      *semantic_name = TGSI_SEMANTIC_COLOR;
+      *semantic_index = frag_result - FRAG_RESULT_DATA0;
+      return;
+   }
+
+   *semantic_index = 0;
+
+   switch (frag_result) {
+   case FRAG_RESULT_DEPTH:
+      *semantic_name = TGSI_SEMANTIC_POSITION;
+      break;
+   case FRAG_RESULT_STENCIL:
+      *semantic_name = TGSI_SEMANTIC_STENCIL;
+      break;
+   case FRAG_RESULT_COLOR:
+      *semantic_name = TGSI_SEMANTIC_COLOR;
+      break;
+   case FRAG_RESULT_SAMPLE_MASK:
+      *semantic_name = TGSI_SEMANTIC_SAMPLEMASK;
+      break;
+   default:
+      assert(false);
+   }
+}
diff --git a/src/gallium/auxiliary/tgsi/tgsi_from_mesa.h b/src/gallium/auxiliary/tgsi/tgsi_from_mesa.h
index d0f211e..bfaa48d 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_from_mesa.h
+++ b/src/gallium/auxiliary/tgsi/tgsi_from_mesa.h
@@ -35,20 +35,25 @@
 void
 tgsi_get_gl_varying_semantic(gl_varying_slot attr,
                              bool needs_texcoord_semantic,
                              unsigned *semantic_name,
                              unsigned *semantic_index);
 
 unsigned
 tgsi_get_generic_gl_varying_index(gl_varying_slot attr,
                                   bool needs_texcoord_semantic);
 
+void
+tgsi_get_gl_frag_result_semantic(gl_frag_result frag_result,
+                                 unsigned *semantic_name,
+                                 unsigned *semantic_index);
+
 static inline enum pipe_shader_type
 pipe_shader_type_from_mesa(gl_shader_stage stage)
 {
    switch (stage) {
    case MESA_SHADER_VERTEX:
       return PIPE_SHADER_VERTEX;
    case MESA_SHADER_TESS_CTRL:
       return PIPE_SHADER_TESS_CTRL;
    case MESA_SHADER_TESS_EVAL:
       return PIPE_SHADER_TESS_EVAL;
-- 
2.9.3