Formalize builtin shader resource contracts

engine/src/Rendering/Detail/ShaderVariantUtils.h

@@ -87,32 +87,16 @@ inline bool TryCollectShaderPassResourceBindings(
     Containers::Array<Resources::ShaderResourceBindingDesc>& outBindings) {
     outBindings.Clear();
 
-    if (!pass.resources.Empty()) {
-        outBindings.Reserve(pass.resources.Size());
-        for (const Resources::ShaderResourceBindingDesc& binding : pass.resources) {
-            outBindings.PushBack(binding);
-        }
-        return true;
+    if (pass.resources.Empty()) {
+        return false;
     }
 
-    return TryBuildImplicitBuiltinPassResourceBindings(pass, outBindings);
-}
-
-inline Containers::String ResolveLegacyHlslBindingDeclarationAlias(
-    const Resources::ShaderResourceBindingDesc& binding) {
-    switch (ResolveBuiltinPassResourceSemantic(binding)) {
-    case BuiltinPassResourceSemantic::BaseColorTexture:
-        return "gBaseColorTexture";
-    case BuiltinPassResourceSemantic::ShadowMapTexture:
-        return "gShadowMapTexture";
-    case BuiltinPassResourceSemantic::LinearClampSampler:
-        return "gLinearSampler";
-    case BuiltinPassResourceSemantic::ShadowMapSampler:
-        return "gShadowMapSampler";
-    case BuiltinPassResourceSemantic::Unknown:
-    default:
-        return Containers::String();
+    outBindings.Reserve(pass.resources.Size());
+    for (const Resources::ShaderResourceBindingDesc& binding : pass.resources) {
+        outBindings.PushBack(binding);
     }
+
+    return true;
 }
 
 inline bool TryRewriteHlslRegisterBindingWithName(
@@ -201,37 +185,6 @@ inline bool TryRewriteHlslRegisterBinding(
         return true;
     }
 
-    const Containers::String legacyAlias = ResolveLegacyHlslBindingDeclarationAlias(binding);
-    if (legacyAlias != binding.name &&
-        TryRewriteHlslRegisterBindingWithName(
-            sourceText,
-            legacyAlias,
-            registerPrefix,
-            binding.binding,
-            binding.set,
-            includeRegisterSpace,
-            binding.type)) {
-        return true;
-    }
-
-    if ((binding.type == Resources::ShaderResourceType::Texture2D ||
-         binding.type == Resources::ShaderResourceType::TextureCube ||
-         binding.type == Resources::ShaderResourceType::Sampler)) {
-        const Containers::String prefixedName = Containers::String("g") + binding.name;
-        if (prefixedName != binding.name &&
-            prefixedName != legacyAlias &&
-            TryRewriteHlslRegisterBindingWithName(
-                sourceText,
-                prefixedName,
-                registerPrefix,
-                binding.binding,
-                binding.set,
-                includeRegisterSpace,
-                binding.type)) {
-            return true;
-        }
-    }
-
     return false;
 }
 
@@ -243,21 +196,18 @@ inline bool TryBuildRuntimeShaderBindings(
     outBindings.Clear();
     outIncludeRegisterSpace = false;
 
+    if (!TryCollectShaderPassResourceBindings(pass, outBindings)) {
+        return false;
+    }
+
     if (backend == Resources::ShaderBackend::Vulkan) {
         outIncludeRegisterSpace = true;
-        return TryCollectShaderPassResourceBindings(pass, outBindings);
+        return true;
     }
 
     if (backend != Resources::ShaderBackend::D3D12 &&
         backend != Resources::ShaderBackend::OpenGL) {
-        return false;
-    }
-
-    if (!pass.resources.Empty()) {
-        return false;
-    }
-
-    if (!TryBuildImplicitBuiltinPassResourceBindings(pass, outBindings)) {
+        outBindings.Clear();
         return false;
     }
 

engine/src/Resources/Shader/Internal/ShaderRuntimeBuildUtils.cpp

@@ -6,6 +6,7 @@
 #include "ShaderFileUtils.h"
 
 #include <XCEngine/Core/Asset/ResourceManager.h>
+#include <XCEngine/Rendering/Builtin/BuiltinPassLayoutUtils.h>
 #include <XCEngine/Resources/BuiltinResources.h>
 #include <XCEngine/Resources/Shader/ShaderLoader.h>
 
@@ -207,6 +208,14 @@ ShaderPass BuildConcretePass(
     for (const ShaderResourceBindingDesc& resourceBinding : pass.resources) {
         shaderPass.resources.PushBack(resourceBinding);
     }
+    if (shaderPass.resources.Empty()) {
+        Containers::Array<ShaderResourceBindingDesc> defaultBindings;
+        if (::XCEngine::Rendering::TryBuildBuiltinPassDefaultResourceBindings(shaderPass, defaultBindings)) {
+            for (const ShaderResourceBindingDesc& resourceBinding : defaultBindings) {
+                shaderPass.resources.PushBack(resourceBinding);
+            }
+        }
+    }
     for (const ShaderKeywordDeclaration& keywordDeclaration : pass.keywordDeclarations) {
         shaderPass.keywordDeclarations.PushBack(keywordDeclaration);
     }