From 135ff5e7a51a56c06f5c44a7c65fe6c9f334eb05 Mon Sep 17 00:00:00 2001
From: Hans-Kristian Arntzen <maister@archlinux.us>
Date: Mon, 24 Jun 2019 14:25:04 +0200
Subject: [PATCH] Fixup resource remapping in MSL/HLSL.

Seemed rather sketchy, but this must be tested a bit.
---
 gfx/drivers_shader/slang_process.cpp | 74 +++++++++++++++-------------
 1 file changed, 40 insertions(+), 34 deletions(-)

diff --git a/gfx/drivers_shader/slang_process.cpp b/gfx/drivers_shader/slang_process.cpp
index 397b6e02e4..d4c40360ad 100644
--- a/gfx/drivers_shader/slang_process.cpp
+++ b/gfx/drivers_shader/slang_process.cpp
@@ -450,35 +450,8 @@ bool slang_process(
          options.shader_model     = version;
          vs->set_hlsl_options(options);
          ps->set_hlsl_options(options);
-
-#if 0
-         CompilerGLSL::Options glsl_options;
-         glsl_options.vertex.flip_vert_y = true;
-         ((CompilerGLSL*)vs)->set_options(glsl_options);
-         ((CompilerGLSL*)ps)->set_options(glsl_options);
-#endif
-
-         /* not exactly a vertex attribute but this remaps
-          * float2 FragCoord :TEXCOORD# to float4 FragCoord : SV_POSITION */
-         std::vector<HLSLVertexAttributeRemap> ps_attrib_remap;
-
-         VariableTypeRemapCallback ps_var_remap_cb =
-               [&](const SPIRType& type, const std::string& var_name, std::string& name_of_type) {
-                  if (var_name == "FragCoord")
-                     name_of_type = "float4";
-               };
-         for (Resource& resource : ps_resources.stage_inputs)
-         {
-            if (ps->get_name(resource.id) == "FragCoord")
-            {
-               uint32_t location = ps->get_decoration(resource.id, spv::DecorationLocation);
-               ps_attrib_remap.push_back({ location, "SV_Position" });
-               ps->set_variable_type_remap_callback(ps_var_remap_cb);
-            }
-         }
-
          vs_code = vs->compile();
-         ps_code = ps->compile(ps_attrib_remap);
+         ps_code = ps->compile();
       }
       else
 #endif
@@ -491,13 +464,46 @@ bool slang_process(
          vs->set_msl_options(options);
          ps->set_msl_options(options);
 
-         std::vector<MSLVertexAttr> vs_attrib_remap;
-         std::vector<MSLResourceBinding> vs_res;
+         const auto remap_push_constant = [](CompilerMSL *comp,
+                                             const ShaderResources &resources) {
+            for (const Resource& resource : resources.push_constant_buffers)
+            {
+               // Explicit 1:1 mapping for bindings.
+               MSLResourceBinding binding = {};
+               binding.stage = comp->get_execution_model();
+               binding.desc_set = kPushConstDescSet;
+               binding.binding = kPushConstBinding;
+               // Use earlier decoration override.
+               binding.msl_buffer = comp->get_decoration(resource.id, spv::DecorationBinding);
+               comp->add_msl_resource_binding(binding);
+            }
+         };
 
-         for (Resource& resource : vs_resources.stage_inputs)
-         {
-            std::string name = vs->get_name(resource.id);
-         }
+         const auto remap_generic_resource = [](CompilerMSL *comp,
+                                                const SmallVector<Resource> &resources) {
+            for (const Resource& resource : resources)
+            {
+               // Explicit 1:1 mapping for bindings.
+               MSLResourceBinding binding = {};
+               binding.stage = comp->get_execution_model();
+               binding.desc_set = comp->get_decoration(resource.id, spv::DecorationDescriptorSet);
+
+               // Use existing decoration override.
+               uint32_t msl_binding = comp->get_decoration(resource.id, spv::DecorationBinding);
+               binding.binding      = msl_binding;
+               binding.msl_buffer   = msl_binding;
+               binding.msl_texture  = msl_binding;
+               binding.msl_sampler  = msl_binding;
+               comp->add_msl_resource_binding(binding);
+            }
+         };
+
+         remap_push_constant(vs, vs_resources);
+         remap_push_constant(ps, ps_resources);
+         remap_generic_resource(vs, vs_resources.uniform_buffers);
+         remap_generic_resource(ps, ps_resources.uniform_buffers);
+         remap_generic_resource(vs, vs_resources.sampled_images);
+         remap_generic_resource(ps, ps_resources.sampled_images);
 
          vs_code = vs->compile();
          ps_code = ps->compile();