Hotfix/texture2d gather (#876)

* First pass test to see if GatherRed works.

* Add support for generating R_Float32 textures.

* Set default texture format.

* * Alter the texture2d-gather to work with a R_Float32 texture
* Add support for scalar Texture2d types with GatherXXX in stdlib

* Remove some left over commented out test code from texture2d-gather.hlsl

3 files changed, 77 insertions, 5 deletions

diff --git a/tools/render-test/shader-input-layout.cpp b/tools/render-test/shader-input-layout.cpp
index 5a2021b01..6d51a1980 100644
--- a/tools/render-test/shader-input-layout.cpp
+++ b/tools/render-test/shader-input-layout.cpp
@@ -208,10 +208,25 @@ namespace renderer_test
                                 }
                                 else if(word == "format")
                                 {
+                                    Format format = Format::Unknown;
+
                                     parser.Read("=");
                                     auto formatWord = parser.ReadWord();
                                     if(formatWord == "R_UInt32")
-                                        entry.bufferDesc.format = Format::R_UInt32;
+                                    {
+                                        format = Format::R_UInt32;
+                                    }
+                                    else if (formatWord == "R_Float32")
+                                    {
+                                        format = Format::R_Float32;
+                                    }
+                                    else if (formatWord == "RGBA_Unorm_UInt8")
+                                    {
+                                        format = Format::RGBA_Unorm_UInt8;
+                                    }
+
+                                    entry.textureDesc.format = format;
+                                    entry.bufferDesc.format = format;
                                 }
                                 if (parser.LookAhead(","))
                                     parser.Read(",");
@@ -265,15 +280,64 @@ namespace renderer_test
                 }
             }
         }
+    }
+
+    void generateTextureData(TextureData& output, const InputTextureDesc& desc)
+    {
+        switch (desc.format)
+        {
+            case Format::RGBA_Unorm_UInt8:
+            {
+                generateTextureDataRGB8(output, desc);
+                break;
+            }
+            case Format::R_Float32:
+            {
+                TextureData work;
+                generateTextureDataRGB8(work, desc);
 
+                output.textureSize = work.textureSize;
+                output.mipLevels = work.mipLevels;
+                output.arraySize = work.arraySize;
 
+                List<List<unsigned int>>& dstBuffer = output.dataBuffer;
+
+                int numMips = int(work.dataBuffer.Count());
+                dstBuffer.SetSize(numMips);
+
+                for (int i = 0; i < numMips; ++i)
+                {
+                    const int numPixels = int(work.dataBuffer[i].Count());
+                    const unsigned int* srcPixels = work.dataBuffer[i].Buffer();
+
+                    dstBuffer[i].SetSize(numPixels);
+
+                    float* dstPixels = (float*)dstBuffer[i].Buffer();
+
+                    for (int j = 0; j < numPixels; ++j)
+                    {
+                        // Copy out red
+                        const unsigned int srcPixel = srcPixels[j];
+                        const float value = (srcPixel & 0xff) * 1.0f / 255;
+                        dstPixels[j] = value;
+                    }
+                }
+                break;
+            }
+            default:
+            {
+                SLANG_ASSERT(!"Unhandled format");
+                break;
+            }
+        }
     }
-    void generateTextureData(TextureData & output, const InputTextureDesc & inputDesc)
+
+    void generateTextureDataRGB8(TextureData& output, const InputTextureDesc& inputDesc)
     {
         int arrLen = inputDesc.arrayLength;
         if (arrLen == 0)
             arrLen = 1;
-        List<List<unsigned int>> & dataBuffer = output.dataBuffer;
+        List<List<unsigned int>>& dataBuffer = output.dataBuffer;
         int arraySize = arrLen;
         if (inputDesc.isCube)
             arraySize *= 6;
diff --git a/tools/render-test/shader-input-layout.h b/tools/render-test/shader-input-layout.h
index 1044a6eea..d9188fadd 100644
--- a/tools/render-test/shader-input-layout.h
+++ b/tools/render-test/shader-input-layout.h
@@ -27,6 +27,9 @@ struct InputTextureDesc
     bool isDepthTexture = false;
     bool isRWTexture = false;
     int size = 4;
+
+    Format format = Format::RGBA_Unorm_UInt8;            
+
     InputTextureContent content = InputTextureContent::One;
 };
 
@@ -80,7 +83,9 @@ public:
     void Parse(const char * source);
 };
 
-void generateTextureData(TextureData & output, const InputTextureDesc & desc);
+void generateTextureDataRGB8(TextureData& output, const InputTextureDesc& desc);
+void generateTextureData(TextureData& output, const InputTextureDesc& desc);
+
 
 } // namespace render_test
 
diff --git a/tools/render-test/shader-renderer-util.cpp b/tools/render-test/shader-renderer-util.cpp
index 0d0f8a3a5..3dc717c5b 100644
--- a/tools/render-test/shader-renderer-util.cpp
+++ b/tools/render-test/shader-renderer-util.cpp
@@ -28,7 +28,10 @@ void BindingStateImpl::apply(Renderer* renderer, PipelineType pipelineType)
     TextureResource::Desc textureResourceDesc;
     textureResourceDesc.init(Resource::Type::Unknown);
 
-    textureResourceDesc.format = Format::RGBA_Unorm_UInt8;
+    // Default to RGBA_Unorm_UInt8
+    const Format format = (inputDesc.format == Format::Unknown) ? Format::RGBA_Unorm_UInt8 : inputDesc.format;
+
+    textureResourceDesc.format = format;
     textureResourceDesc.numMipLevels = texData.mipLevels;
     textureResourceDesc.arraySize = inputDesc.arrayLength;
     textureResourceDesc.bindFlags = bindFlags;