add fog

Author: rfdickerson

CMakeLists.txt

@@ -69,7 +69,7 @@ add_library(ReactorLib STATIC
 )
 
 target_compile_definitions(ReactorLib PUBLIC GLM_ENABLE_EXPERIMENTAL)
-
+target_compile_definitions(ReactorLib PUBLIC GLM_FORCE_DEPTH_ZERO_TO_ONE)
 
 target_link_libraries(ReactorLib PUBLIC
         Vulkan::Vulkan

shaders/composite.frag

@@ -14,6 +14,7 @@ layout(set = 0, binding = 1) uniform CompositeParams {
     float uSaturation;  // Default: 1.0
     float uVignetteIntensity;   // Default: 0.5
     float uVignetteFalloff;     // Default 0.5
+    float uFogDensity;
 };
 
 // add camera projection uniforms to the UBO or pass them in another way
@@ -47,7 +48,8 @@ void main() {
         float fogEnd = 5.0;
         float viewDistance = linearizeDepth(depth);
         // Calculate fog amount (0.0 = no fog, 1.0 = full fog)
-        float fogFactor = smoothstep(fogStart, fogEnd, viewDistance);
+        //float fogFactor = smoothstep(fogStart, fogEnd, viewDistance);
+    float fogFactor = uFogDensity;
         // ----------------------
 
     // Sample the HDR input image
@@ -70,7 +72,7 @@ void main() {
     finalColor = mix(grayscale, finalColor, uSaturation);
 
     // Mix the final scene color with the fog color
-    //finalColor = mix(finalColor, fogColor, fogFactor);
+    finalColor = mix(finalColor, fogColor, fogFactor);
 
     outColor = vec4(finalColor, 1.0);
 }

src/core/Camera.cpp

@@ -1,6 +1,5 @@
 #include "Camera.hpp"
 
-#define GLM_ENABLE_EXPERIMENTAL
 #include <glm/gtc/matrix_transform.hpp>
 #include <glm/gtc/constants.hpp>
 #include <glm/gtx/euler_angles.hpp>

src/core/Uniforms.hpp

@@ -11,6 +11,8 @@ struct DirectionalLightUBO
     glm::vec4 lightPosition = glm::vec4(-0.5f, 1.0f, -0.5f, 0.0f);
     glm::vec4 lightColor = glm::vec4(1.0f, 1.0f, 1.0f, 1.0f);
     float lightIntensity = 1.0f;
+    // add 12-bytes of padding
+    float pad[3];
 };
 
 struct CompositeUBO {
@@ -19,4 +21,5 @@ struct CompositeUBO {
     float uSaturation = 1.0f;
     float uVignetteIntensity = 0.5f;
     float uVignetteFalloff = 0.5f;
+    float uFogDensity = 0.001f;
 };

src/imgui/Imgui.cpp

@@ -191,6 +191,8 @@ void Imgui::ShowInspector() {
     ImGui::SliderFloat("Exposure", &m_exposure, 0.0, 2.0);
     ImGui::SliderFloat("Contrast", &m_contrast, 0.0, 2.0);
     ImGui::SliderFloat("Saturation", &m_saturation, 0.0, 2.0);
+
+    ImGui::SliderFloat("Fog Density", &m_fogDensity, 0.0, 0.5);
     ImGui::End();
 }
 

src/imgui/Imgui.hpp

@@ -22,6 +22,7 @@ class Imgui {
     [[nodiscard]] float getExposure() const { return m_exposure; }
     [[nodiscard]] float getContrast() const { return m_contrast; }
     [[nodiscard]] float getSaturation() const { return m_saturation; }
+    [[nodiscard]] float getFogDensity() const { return m_fogDensity; }
 
     static vk::DescriptorSet createDescriptorSet(vk::ImageView imageView, vk::Sampler sampler);
     void setSceneDescriptorSet(const vk::DescriptorSet descriptorSet) { m_sceneImguiId = descriptorSet; };
@@ -37,6 +38,7 @@ class Imgui {
     float m_exposure = 1.0f;
     float m_contrast = 1.0f;
     float m_saturation = 1.0f;
+    float m_fogDensity = 0.001f;
 
     void ShowDockspace();
     void ShowSceneView();

src/vulkan/VulkanRenderer.cpp

@@ -263,6 +263,7 @@ void VulkanRenderer::drawFrame()
     compositeData.uExposure = m_imgui->getExposure();
     compositeData.uContrast = m_imgui->getContrast();
     compositeData.uSaturation = m_imgui->getSaturation();
+    compositeData.uFogDensity = m_imgui->getFogDensity();
     m_uniformManager->update<CompositeUBO>(frameIdx, compositeData);
 
     SceneUBO ubo{};