Re-implement GLSL texture sampler variables.

GLSL sampler variables indicate which texture unit to use for TEX instructions.
Previously, this was baked into the fragment/vertex program and couldn't be
readily changed once set.
Now, SamplerUnits[] array indicates which texture unit is to be used for
each sampler variable.  These values are set with glUniform1i().
This is extra state that must be passed to the fragment/vertex program
executor at runtime.

1 files changed, 12 insertions, 3 deletions

diff --git a/src/mesa/shader/slang/slang_codegen.c b/src/mesa/shader/slang/slang_codegen.c
index fb1f9d5a20a..767ba3ffb43 100644
--- a/src/mesa/shader/slang/slang_codegen.c
+++ b/src/mesa/shader/slang/slang_codegen.c
@@ -2874,14 +2874,23 @@ _slang_codegen_global_variable(slang_assemble_ctx *A, slang_variable *var,
    const GLint texIndex = sampler_to_texture_index(var->type.specifier.type);
 
    if (texIndex != -1) {
-      /* Texture sampler:
+      /* This is a texture sampler variable...
        * store->File = PROGRAM_SAMPLER
-       * store->Index = sampler uniform location
+       * store->Index = sampler number (0..7, typically)
        * store->Size = texture type index (1D, 2D, 3D, cube, etc)
        */
+#if 0
       GLint samplerUniform
          = _mesa_add_sampler(prog->Parameters, varName, datatype);
-      store = _slang_new_ir_storage(PROGRAM_SAMPLER, samplerUniform, texIndex);
+#elif 0
+      GLint samplerUniform
+         = _mesa_add_sampler(prog->Samplers, varName, datatype);
+      (void) _mesa_add_sampler(prog->Parameters, varName, datatype); /* dummy entry */
+#else
+      const GLint sampNum = A->numSamplers++;
+      _mesa_add_sampler(prog->Parameters, varName, datatype, sampNum);
+#endif
+      store = _slang_new_ir_storage(PROGRAM_SAMPLER, sampNum, texIndex);
       if (dbg) printf("SAMPLER ");
    }
    else if (var->type.qualifier == SLANG_QUAL_UNIFORM) {