Implemented sRGB support in ShaderSets and default format for colour framebuffer

CMakeLists.txt

@@ -1,7 +1,7 @@
 cmake_minimum_required(VERSION 3.7)
 
 project(vsg
-    VERSION 1.1.9
+    VERSION 1.1.10
     DESCRIPTION "VulkanSceneGraph library"
     LANGUAGES CXX
 )

include/vsg/all.h

@@ -287,6 +287,7 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 #include <vsg/utils/Builder.h>
 #include <vsg/utils/CommandLine.h>
 #include <vsg/utils/ComputeBounds.h>
+#include <vsg/utils/CoordinateSpace.h>
 #include <vsg/utils/FindDynamicObjects.h>
 #include <vsg/utils/GpuAnnotation.h>
 #include <vsg/utils/GraphicsPipelineConfigurator.h>

include/vsg/maths/color.h

@@ -96,32 +96,4 @@ namespace vsg
         }
     }
 
-    template<typename T>
-    constexpr t_vec4<T> linear_to_sRGB(const t_vec4<T>& src)
-    {
-        const T exponent = static_cast<T>(2.2);
-        return t_vec4<T>(std::pow(src.r, exponent), std::pow(src.g, exponent), std::pow(src.b, exponent), src.a);
-    }
-
-    template<typename T>
-    constexpr t_vec4<T> linear_to_sRGB(T r, T g, T b, T a)
-    {
-        const T exponent = static_cast<T>(2.2);
-        return t_vec4<T>(std::pow(r, exponent), std::pow(g, exponent), std::pow(b, exponent), a);
-    }
-
-    template<typename T>
-    constexpr t_vec4<T> sRGB_to_linear(const t_vec4<T>& src)
-    {
-        const T exponent = static_cast<T>(1.0 / 2.2);
-        return t_vec4<T>(std::pow(src.r, exponent), std::pow(src.g, exponent), std::pow(src.b, exponent), src.a);
-    }
-
-    template<typename T>
-    constexpr t_vec4<T> sRGB_to_linear(T r, T g, T b, T a)
-    {
-        const T exponent = static_cast<T>(1.0 / 2.2);
-        return t_vec4<T>(std::pow(r, exponent), std::pow(g, exponent), std::pow(b, exponent), a);
-    }
-
 } // namespace vsg

include/vsg/utils/CoordinateSpace.h

@@ -0,0 +1,112 @@
+#pragma once
+
+/* <editor-fold desc="MIT License">
+
+Copyright(c) 2024 Chris Djali
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+</editor-fold> */
+
+#include <vsg/core/Array.h>
+#include <vsg/core/Inherit.h>
+#include <vsg/maths/color.h>
+
+namespace vsg
+{
+
+    enum class CoordinateSpace
+    {
+        NO_PREFERENCE = 0,
+        LINEAR = (1 << 0),
+        sRGB = (1 << 1)
+    };
+
+    template<typename T>
+    constexpr T linear_to_sRGB_component(T c)
+    {
+        constexpr T cutoff = static_cast<T>(0.04045 / 12.92);
+        constexpr T linearFactor = static_cast<T>(12.92);
+        constexpr T nonlinearFactor = static_cast<T>(1.055);
+        constexpr T exponent = static_cast<T>(1.0 / 2.4);
+        if (c <= cutoff)
+            return c * linearFactor;
+        else
+            return std::pow(c, exponent) * nonlinearFactor - static_cast<T>(0.055);
+    }
+
+    template<typename T>
+    constexpr T sRGB_to_linear_component(T c)
+    {
+        constexpr T cutoff = static_cast<T>(0.04045);
+        constexpr T linearFactor = static_cast<T>(1.0 / 12.92);
+        constexpr T nonlinearFactor = static_cast<T>(1.0 / 1.055);
+        constexpr T exponent = static_cast<T>(2.4);
+        if (c <= cutoff)
+            return c * linearFactor;
+        else
+            return std::pow((c + static_cast<T>(0.055)) * nonlinearFactor, exponent);
+    }
+
+    template<typename T>
+    constexpr t_vec3<T> linear_to_sRGB(const t_vec3<T>& src)
+    {
+        return t_vec3<T>(linear_to_sRGB_component(src.r), linear_to_sRGB_component(src.g), linear_to_sRGB_component(src.b));
+    }
+
+    template<typename T>
+    constexpr t_vec4<T> linear_to_sRGB(const t_vec4<T>& src)
+    {
+        return t_vec4<T>(linear_to_sRGB_component(src.r), linear_to_sRGB_component(src.g), linear_to_sRGB_component(src.b), src.a);
+    }
+
+    template<typename T>
+    constexpr t_vec4<T> linear_to_sRGB(T r, T g, T b, T a)
+    {
+        return t_vec4<T>(linear_to_sRGB_component(r), linear_to_sRGB_component(g), linear_to_sRGB_component(b), a);
+    }
+
+    template<typename T>
+    constexpr t_vec3<T> sRGB_to_linear(const t_vec3<T>& src)
+    {
+        return t_vec3<T>(sRGB_to_linear_component(src.r), sRGB_to_linear_component(src.g), sRGB_to_linear_component(src.b));
+    }
+
+    template<typename T>
+    constexpr t_vec4<T> sRGB_to_linear(const t_vec4<T>& src)
+    {
+        return t_vec4<T>(sRGB_to_linear_component(src.r), sRGB_to_linear_component(src.g), sRGB_to_linear_component(src.b), src.a);
+    }
+
+    template<typename T>
+    constexpr t_vec4<T> sRGB_to_linear(T r, T g, T b, T a)
+    {
+        return t_vec4<T>(sRGB_to_linear_component(r), sRGB_to_linear_component(g), sRGB_to_linear_component(b), a);
+    }
+
+    template<typename T>
+    void convert(T& data, CoordinateSpace source, CoordinateSpace target)
+    {
+        if (source == CoordinateSpace::sRGB && target == CoordinateSpace::LINEAR)
+            data = sRGB_to_linear(data);
+        else if (source == CoordinateSpace::LINEAR && target == CoordinateSpace::sRGB)
+            data = linear_to_sRGB(data);
+    }
+
+    template<typename T>
+    void convert(size_t num, T* data, CoordinateSpace source, CoordinateSpace target)
+    {
+        if (source == CoordinateSpace::sRGB && target == CoordinateSpace::LINEAR)
+            for (size_t i = 0; i < num; ++i) data[i] = sRGB_to_linear(data[i]);
+        else if (source == CoordinateSpace::LINEAR && target == CoordinateSpace::sRGB)
+            for (size_t i = 0; i < num; ++i) data[i] = linear_to_sRGB(data[i]);
+    }
+
+    extern VSG_DECLSPEC VkFormat uNorm_to_sRGB(VkFormat format);
+    extern VSG_DECLSPEC VkFormat sRGB_to_uNorm(VkFormat format);
+
+} // namespace vsg

include/vsg/utils/ShaderSet.h

@@ -17,6 +17,7 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 #include <vsg/state/GraphicsPipeline.h>
 #include <vsg/state/Sampler.h>
 #include <vsg/state/ShaderStage.h>
+#include <vsg/utils/CoordinateSpace.h>
 
 namespace vsg
 {
@@ -27,6 +28,7 @@ namespace vsg
         std::string define;
         uint32_t location = 0;
         VkFormat format = VK_FORMAT_UNDEFINED;
+        CoordinateSpace coordinateSpace = CoordinateSpace::NO_PREFERENCE;
         ref_ptr<Data> data;
 
         int compare(const AttributeBinding& rhs) const;
@@ -44,6 +46,7 @@ namespace vsg
         VkDescriptorType descriptorType = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER;
         uint32_t descriptorCount = 0;
         VkShaderStageFlags stageFlags = 0;
+        CoordinateSpace coordinateSpace = CoordinateSpace::NO_PREFERENCE;
         ref_ptr<Data> data;
 
         int compare(const DescriptorBinding& rhs) const;
@@ -133,10 +136,10 @@ namespace vsg
         std::mutex mutex;
 
         /// add an attribute binding, Not thread safe, should only be called when initially setting up the ShaderSet
-        void addAttributeBinding(const std::string& name, const std::string& define, uint32_t location, VkFormat format, ref_ptr<Data> data);
+        void addAttributeBinding(const std::string& name, const std::string& define, uint32_t location, VkFormat format, ref_ptr<Data> data, CoordinateSpace coordinateSpace = CoordinateSpace::NO_PREFERENCE);
 
         /// add an uniform binding. Not thread safe, should only be called when initially setting up the ShaderSet
-        void addDescriptorBinding(const std::string& name, const std::string& define, uint32_t set, uint32_t binding, VkDescriptorType descriptorType, uint32_t descriptorCount, VkShaderStageFlags stageFlags, ref_ptr<Data> data);
+        void addDescriptorBinding(const std::string& name, const std::string& define, uint32_t set, uint32_t binding, VkDescriptorType descriptorType, uint32_t descriptorCount, VkShaderStageFlags stageFlags, ref_ptr<Data> data, CoordinateSpace coordinateSpace = CoordinateSpace::NO_PREFERENCE);
 
         [[deprecated("use addDescriptorBinding(..)")]] void addUniformBinding(const std::string& name, const std::string& define, uint32_t set, uint32_t binding, VkDescriptorType descriptorType, uint32_t descriptorCount, VkShaderStageFlags stageFlags, ref_ptr<Data> data) { addDescriptorBinding(name, define, set, binding, descriptorType, descriptorCount, stageFlags, data); }
 

include/vsg/vk/Swapchain.h

@@ -27,15 +27,15 @@ namespace vsg
     };
 
     extern VSG_DECLSPEC SwapChainSupportDetails querySwapChainSupport(VkPhysicalDevice device, VkSurfaceKHR surface);
-    extern VSG_DECLSPEC VkSurfaceFormatKHR selectSwapSurfaceFormat(const SwapChainSupportDetails& details, VkSurfaceFormatKHR preferredSurfaceFormat = {VK_FORMAT_B8G8R8A8_UNORM, VK_COLOR_SPACE_SRGB_NONLINEAR_KHR});
+    extern VSG_DECLSPEC VkSurfaceFormatKHR selectSwapSurfaceFormat(const SwapChainSupportDetails& details, VkSurfaceFormatKHR preferredSurfaceFormat = {VK_FORMAT_B8G8R8A8_SRGB, VK_COLOR_SPACE_SRGB_NONLINEAR_KHR});
     extern VSG_DECLSPEC VkExtent2D selectSwapExtent(const SwapChainSupportDetails& details, uint32_t width, uint32_t height);
     extern VSG_DECLSPEC VkPresentModeKHR selectSwapPresentMode(const SwapChainSupportDetails& details, VkPresentModeKHR preferredPresentMode = VK_PRESENT_MODE_MAILBOX_KHR);
 
     /// Swapchain preferences passed via WindowTraits::swapchainPreferences to guide swapchain creation associated with Window creation.
     struct SwapchainPreferences
     {
         uint32_t imageCount = 3; // default to triple buffering
-        VkSurfaceFormatKHR surfaceFormat = {VK_FORMAT_B8G8R8A8_UNORM, VK_COLOR_SPACE_SRGB_NONLINEAR_KHR};
+        VkSurfaceFormatKHR surfaceFormat = {VK_FORMAT_B8G8R8A8_SRGB, VK_COLOR_SPACE_SRGB_NONLINEAR_KHR};
         VkPresentModeKHR presentMode = VK_PRESENT_MODE_FIFO_KHR;
         VkImageUsageFlags imageUsage = VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT;
     };

src/vsg/CMakeLists.txt

@@ -244,6 +244,7 @@ set(SOURCES
     vk/ResourceRequirements.cpp
 
     utils/CommandLine.cpp
+    utils/CoordinateSpace.cpp
     utils/Builder.cpp
     utils/SharedObjects.cpp
     utils/ShaderSet.cpp

src/vsg/app/Window.cpp

@@ -18,6 +18,7 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 #include <vsg/maths/color.h>
 #include <vsg/maths/vec4.h>
 #include <vsg/ui/ApplicationEvent.h>
+#include <vsg/utils/CoordinateSpace.h>
 #include <vsg/vk/SubmitCommands.h>
 
 #include <array>
@@ -40,8 +41,7 @@ Window::Window(ref_ptr<WindowTraits> traits) :
 {
     if (_traits && (_traits->swapchainPreferences.surfaceFormat.format == VK_FORMAT_B8G8R8A8_SRGB || _traits->swapchainPreferences.surfaceFormat.format == VK_FORMAT_B8G8R8_SRGB))
     {
-        _clearColor = linear_to_sRGB(_clearColor);
-        info("Selected sRGB window ", _clearColor);
+        _clearColor = sRGB_to_linear(_clearColor);
     }
 }
 

src/vsg/io/tile.cpp

@@ -37,6 +37,7 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 #include <vsg/state/material.h>
 #include <vsg/ui/UIEvent.h>
 #include <vsg/utils/ComputeBounds.h>
+#include <vsg/utils/CoordinateSpace.h>
 #include <vsg/vk/ResourceRequirements.h>
 
 using namespace vsg;
@@ -164,21 +165,30 @@ vsg::ref_ptr<vsg::Object> tile::read_root(vsg::ref_ptr<const vsg::Options> optio
             {
                 auto imagePath = getTilePath(settings->imageLayer, x, y, lod);
                 imageData = vsg::read_cast<vsg::Data>(imagePath, options);
-                if (imageData && settings->imageLayerCallback) imageData = settings->imageLayerCallback(imageData);
+                if (imageData && settings->imageLayerCallback)
+                {
+                    imageData = settings->imageLayerCallback(imageData);
+                }
             }
 
             if (settings->detailLayer)
             {
                 auto detailPath = getTilePath(settings->detailLayer, x, y, lod);
                 detailData = vsg::read_cast<vsg::Data>(detailPath, options);
-                if (detailData && settings->detailLayerCallback) detailData = settings->detailLayerCallback(detailData);
+                if (detailData && settings->detailLayerCallback)
+                {
+                    detailData = settings->detailLayerCallback(detailData);
+                }
             }
 
             if (settings->elevationLayer)
             {
                 auto terrainPath = getTilePath(settings->elevationLayer, x, y, lod);
                 elevationData = vsg::read_cast<vsg::Data>(terrainPath, options);
-                if (elevationData && settings->elevationLayerCallback) elevationData = settings->elevationLayerCallback(elevationData);
+                if (elevationData && settings->elevationLayerCallback)
+                {
+                    elevationData = settings->elevationLayerCallback(elevationData);
+                }
             }
 
             auto tile_extents = computeTileExtents(x, y, lod);
@@ -594,14 +604,14 @@ vsg::ref_ptr<vsg::Node> tile::createECEFTile(const vsg::dbox& tile_extents, ref_
     auto scenegraph = vsg::StateGroup::create();
 
     double tileReferenceSize = vsg::radians(tile_extents.max.y - tile_extents.min.y) * settings->ellipsoidModel->radiusEquator();
-    vec3 displacementMapScale(tileReferenceSize, tileReferenceSize, settings->elevationScale);
+    vec3 displacementMapScale(static_cast<float>(tileReferenceSize), static_cast<float>(tileReferenceSize), static_cast<float>(settings->elevationScale));
 
     if (elevationData)
     {
         switch (elevationData->properties.format)
         {
-        case (VK_FORMAT_R16_SFLOAT): displacementMapScale.z = 1.0; break;
-        case (VK_FORMAT_R32_SFLOAT): displacementMapScale.z = 1.0; break;
+        case (VK_FORMAT_R16_SFLOAT): displacementMapScale.z = 1.0f; break;
+        case (VK_FORMAT_R32_SFLOAT): displacementMapScale.z = 1.0f; break;
         default: break;
         }
     }
@@ -829,7 +839,17 @@ vsg::ref_ptr<vsg::Node> tile::createTextureQuad(const vsg::dbox& tile_extents, r
     Origin origin = vsg::TOP_LEFT;
 
     double tileReferenceSize = tile_extents.max.y - tile_extents.min.y;
-    vec3 displacementMapScale(tileReferenceSize, tileReferenceSize, settings->elevationScale);
+    vec3 displacementMapScale(static_cast<float>(tileReferenceSize), static_cast<float>(tileReferenceSize), static_cast<float>(settings->elevationScale));
+
+    if (elevationData)
+    {
+        switch (elevationData->properties.format)
+        {
+        case (VK_FORMAT_R16_SFLOAT): displacementMapScale.z = 1.0f; break;
+        case (VK_FORMAT_R32_SFLOAT): displacementMapScale.z = 1.0f; break;
+        default: break;
+        }
+    }
 
     // create StateGroup to bind any texture state
     auto scenegraph = vsg::StateGroup::create();

src/vsg/lighting/Light.cpp

@@ -74,12 +74,12 @@ ref_ptr<vsg::Node> vsg::createHeadlight()
     auto ambientLight = vsg::AmbientLight::create();
     ambientLight->name = "ambient";
     ambientLight->color.set(1.0f, 1.0f, 1.0f);
-    ambientLight->intensity = 0.05f;
+    ambientLight->intensity = 0.0044f;
 
     auto directionalLight = vsg::DirectionalLight::create();
     directionalLight->name = "headlight";
     directionalLight->color.set(1.0f, 1.0f, 1.0f);
-    directionalLight->intensity = 0.95f;
+    directionalLight->intensity = 0.9956f;
     directionalLight->direction.set(0.0, 0.0, -1.0);
 
     auto absoluteTransform = vsg::AbsoluteTransform::create();

src/vsg/text/GpuLayoutTechnique.cpp

@@ -236,12 +236,12 @@ void GpuLayoutTechnique::setup(Text* text, uint32_t minimumAllocation, ref_ptr<c
         }
     };
 
-    ConvertString convert(*(text->font), textArray, textArrayUpdated, minimumAllocation);
-    text->text->accept(convert);
+    ConvertString converter(*(text->font), textArray, textArrayUpdated, minimumAllocation);
+    text->text->accept(converter);
 
-    if (convert.allocatedSize == 0) return;
+    if (converter.allocatedSize == 0) return;
 
-    uint32_t num_quads = convert.size;
+    uint32_t num_quads = converter.size;
 
     // set up the layout data in a form digestible by the GPU.
     if (!layoutValue)