rendering: thread global shader keywords into builtin variants

engine/src/Rendering/Execution/CameraRenderer.cpp

@@ -45,6 +45,17 @@ std::unique_ptr<RenderPipeline> CreatePipelineFromAsset(
     return std::make_unique<Pipelines::BuiltinForwardPipeline>();
 }
 
+Resources::ShaderKeywordSet BuildSceneGlobalShaderKeywords(
+    const RenderSceneData& sceneData) {
+    Resources::ShaderKeywordSet keywords = {};
+    if (sceneData.lighting.HasMainDirectionalShadow()) {
+        keywords.enabledKeywords.PushBack("XC_MAIN_LIGHT_SHADOWS");
+    }
+
+    Resources::NormalizeShaderKeywordSetInPlace(keywords);
+    return keywords;
+}
+
 bool InitializeStandalonePass(
     RenderPass* pass,
     const RenderContext& context) {
@@ -563,6 +574,7 @@ bool CameraRenderer::BuildSceneDataForRequest(
         outSceneData.lighting.mainDirectionalShadow =
             BuildDirectionalShadowData(request.directionalShadow, shadowMapView);
     }
+    outSceneData.globalShaderKeywords = BuildSceneGlobalShaderKeywords(outSceneData);
 
     outSceneData.cameraData.clearFlags = request.clearFlags;
     outSceneData.environment = BuildEnvironmentData(request);