fix: use buffer binding point instead of index

src/ObjCompiling/Techset/CommonShaderArgCreator.cpp

@@ -408,12 +408,20 @@ namespace
         {
             assert(m_shader_info);
 
-            auto bufferIndex = 0uz;
             auto usedConstantIndex = 0uz;
-            const auto bufferCount = m_shader_info->m_constant_buffers.size();
-            while (bufferIndex < bufferCount)
+            for (const auto& buffer : m_shader_info->m_constant_buffers)
             {
-                const auto& buffer = m_shader_info->m_constant_buffers[bufferIndex];
+                const auto bufferBinding =
+                    std::ranges::find_if(m_shader_info->m_bound_resources,
+                                         [buffer](const d3d11::BoundResource& boundResource)
+                                         {
+                                             return boundResource.m_type == d3d11::BoundResourceType::CBUFFER && boundResource.m_name == buffer.m_name;
+                                         });
+                if (bufferBinding == m_shader_info->m_bound_resources.end())
+                {
+                    errorMessage = std::format("Failed to find binding for constant buffer {}", buffer.m_name);
+                    return false;
+                }
 
                 auto variableIterator = buffer.m_variables.begin();
                 const auto variableEnd = buffer.m_variables.end();
@@ -439,15 +447,13 @@ namespace
                     const auto variableElementSize = variableIterator->m_size / variableElementCount;
                     commonDestination.dx11.m_location.constant_buffer_offset = variableIterator->m_offset + variableElementSize * inputArgumentIndex;
                     commonDestination.dx11.m_size = variableElementSize;
-                    commonDestination.dx11.m_buffer = static_cast<unsigned>(bufferIndex);
+                    commonDestination.dx11.m_buffer = bufferBinding->m_bind_point;
                     isTransposed = variableIterator->m_variable_class == d3d11::VariableClass::MATRIX_COLUMNS;
 
                     m_const_arg_added[usedConstantIndex] = true;
 
                     return true;
                 }
-
-                bufferIndex++;
             }
 
             return false;
@@ -514,12 +520,20 @@ namespace
 
         result::Expected<NoResult, std::string> AutoCreateMissingArgs() override
         {
-            size_t bufferIndex = 0;
             size_t usedConstantCount = 0;
             size_t textureCount = 0;
 
             for (const auto& buffer : m_shader_info->m_constant_buffers)
             {
+                const auto bufferBinding =
+                    std::ranges::find_if(m_shader_info->m_bound_resources,
+                                         [buffer](const d3d11::BoundResource& boundResource)
+                                         {
+                                             return boundResource.m_type == d3d11::BoundResourceType::CBUFFER && boundResource.m_name == buffer.m_name;
+                                         });
+                if (bufferBinding == m_shader_info->m_bound_resources.end())
+                    return result::Unexpected(std::format("Failed to find binding for constant buffer {}", buffer.m_name));
+
                 for (const auto& variable : buffer.m_variables)
                 {
                     if (!variable.m_is_used)
@@ -528,12 +542,10 @@ namespace
                     if (m_const_arg_added[usedConstantCount++])
                         continue;
 
-                    auto result = AutoCreateConstantArg(variable, bufferIndex);
+                    auto result = AutoCreateConstantArg(variable, bufferBinding->m_bind_point);
                     if (!result)
                         return std::move(result);
                 }
-
-                bufferIndex++;
             }
 
             for (const auto& maybeTextureResource : m_shader_info->m_bound_resources)

test/ObjCompilingTests/Game/T6/Techset/TechniqueCompilerT6Test.cpp

@@ -8,6 +8,7 @@
 #include "SearchPath/MockSearchPath.h"
 #include "Shader/ShaderCommon.h"
 #include "Utils/MemoryManager.h"
+#include "catch2/generators/catch_generators.hpp"
 
 #include <catch2/catch_test_macros.hpp>
 #include <filesystem>
@@ -72,7 +73,8 @@ TEST_CASE("TechniqueCompilerT6", "[t6][techset][compiler]")
 
     SECTION("Can compile simple technique")
     {
-        searchPath.AddFileData("techniques/pimp_technique_zprepass_example.tech", R"TECHNIQUE(
+        const auto [inputName, inputData] = GENERATE(Catch::Generators::table<const char*, const char*>({
+            {"auto-create args", R"TECHNIQUE(
 {
   stateMap "passthrough";
 
@@ -86,7 +88,28 @@ TEST_CASE("TechniqueCompilerT6", "[t6][techset][compiler]")
 
   vertex.position = code.position;
 }
-)TECHNIQUE");
+)TECHNIQUE"},
+            {"manual args",      R"TECHNIQUE(
+{
+  stateMap "passthrough";
+
+  vertexShader 4.0 "simple.hlsl"
+  {
+    worldMatrix = constant.worldMatrix;
+    viewProjectionMatrix = constant.viewProjectionMatrix;
+  }
+
+  pixelShader 4.0 "simple.hlsl"
+  {
+  }
+
+  vertex.position = code.position;
+}
+)TECHNIQUE"},
+        }));
+
+        CAPTURE(inputName);
+        searchPath.AddFileData("techniques/pimp_technique_zprepass_example.tech", inputData);
 
         GivenVertexShaderFile("simple.hlsl", searchPath);
         GivenPixelShaderFile("simple.hlsl", searchPath);
@@ -147,7 +170,8 @@ TEST_CASE("TechniqueCompilerT6", "[t6][techset][compiler]")
 
     SECTION("Can compile advanced technique")
     {
-        searchPath.AddFileData("techniques/example_lit_sun_shadow.tech", R"TECHNIQUE(
+        const auto [inputName, inputData] = GENERATE(Catch::Generators::table<const char*, const char*>({
+            {"auto-create args", R"TECHNIQUE(
 {
   stateMap "passthrough";
 
@@ -176,7 +200,47 @@ TEST_CASE("TechniqueCompilerT6", "[t6][techset][compiler]")
   vertex.texcoord[4] = code.texcoord[3];
   vertex.texcoord[5] = code.normalTransform[0];
 }
-)TECHNIQUE");
+)TECHNIQUE"},
+            {"manual args",      R"TECHNIQUE(
+{
+  stateMap "passthrough";
+
+  vertexShader 4.0 "advanced.hlsl"
+  {
+    worldMatrix = constant.worldMatrix;
+    viewProjectionMatrix = constant.viewProjectionMatrix;
+    shadowLookupMatrix = constant.shadowLookupMatrix;
+  }
+
+  pixelShader 4.0 "advanced.hlsl"
+  {
+    normalMapSampler = material.normalMap;
+    normalMapSampler1 = material.normalMap1;
+    colorMapSampler = material.colorMap;
+    colorMapSampler1 = material.colorMap1;
+    colorMapSampler3 = material.colorMap3;
+    colorMapSampler2 = material.colorMap2;
+    shadowmapSamplerSun = sampler.shadowmapSamplerSun;
+    shadowmapSwitchPartition = constant.shadowmapSwitchPartition;
+    sunShadowmapPixelSize = constant.sunShadowmapPixelSize;
+    alphaRevealParms1 = material.alphaRevealParms1;
+  }
+
+  vertex.position = code.position;
+  vertex.color[0] = code.color;
+  vertex.texcoord[0] = code.texcoord[0];
+  vertex.normal = code.normal;
+  vertex.texcoord[2] = code.tangent;
+  vertex.texcoord[1] = code.texcoord[1];
+  vertex.texcoord[3] = code.texcoord[2];
+  vertex.texcoord[4] = code.texcoord[3];
+  vertex.texcoord[5] = code.normalTransform[0];
+}
+)TECHNIQUE"},
+        }));
+
+        CAPTURE(inputName);
+        searchPath.AddFileData("techniques/example_lit_sun_shadow.tech", inputData);
 
         GivenVertexShaderFile("advanced.hlsl", searchPath);
         GivenPixelShaderFile("advanced.hlsl", searchPath);