Add profiling heatmap as per "Profiling DXR Shaders with Timer Instru…

…mentation" (#12)

* Add profiling heatmap as per https://www.reddit.com/r/vulkan/comments/hhyeyj/profiling_dxr_shaders_with_timer_instrumentation/

* Add reference.

* Fix SDK version (older version got pulled from website).

* Fix shader typo.

* Fix validation errors.

* Add gallery heatmap screenshot

* Add lucy heatmap to gallery.

README.md

@@ -10,7 +10,7 @@ This personal project follows my own attempts at CPU ray tracing following Peter
 
 ## Gallery
 
-<img src="https://github.com/GPSnoopy/RayTracingInVulkan/blob/master/gallery/OneWeekend.jpg" width="49%"></img> <img src="https://github.com/GPSnoopy/RayTracingInVulkan/blob/master/gallery/Planets.jpg" width="49%"></img> <img src="https://github.com/GPSnoopy/RayTracingInVulkan/blob/master/gallery/CornellBox.jpg" width="49%"></img> <img src="https://github.com/GPSnoopy/RayTracingInVulkan/blob/master/gallery/CornellBoxLucy.jpg" width="49%"></img>
+<img src="https://github.com/GPSnoopy/RayTracingInVulkan/blob/master/gallery/OneWeekend.jpg" width="49%"></img> <img src="https://github.com/GPSnoopy/RayTracingInVulkan/blob/master/gallery/Planets.jpg" width="49%"></img> <img src="https://github.com/GPSnoopy/RayTracingInVulkan/blob/Heatmap/gallery/Heatmap.png" width="49%"></img> <img src="https://github.com/GPSnoopy/RayTracingInVulkan/blob/Heatmap/gallery/LucyHeatmap.png" width="49%"></img> <img src="https://github.com/GPSnoopy/RayTracingInVulkan/blob/master/gallery/CornellBox.jpg" width="49%"></img> <img src="https://github.com/GPSnoopy/RayTracingInVulkan/blob/master/gallery/CornellBoxLucy.jpg" width="49%"></img>
 
 ## Performance
 
@@ -78,6 +78,7 @@ If in doubt, please check the GitHub Actions [continuous integration configurati
 * [D3D12 Raytracing Samples](https://github.com/Microsoft/DirectX-Graphics-Samples/tree/master/Samples/Desktop/D3D12Raytracing)
 * [George Ouzounoudis's vk_exp](https://github.com/georgeouzou/vk_exp)
 * [NVIDIA Vulkan Forums](https://devtalk.nvidia.com/default/board/166/vulkan)
+* [Profiling DXR shaders with Timer Instrumentation](https://www.reddit.com/r/vulkan/comments/hhyeyj/profiling_dxr_shaders_with_timer_instrumentation/)
 
 ### VK_KHR_ray_tracing Port
 

assets/shaders/Heatmap.glsl

@@ -0,0 +1,33 @@
+
+// Profiling DXR Shaders with Timer Instrumentation
+// https://developer.nvidia.com/blog/profiling-dxr-shaders-with-timer-instrumentation/
+vec3 heatmap(float t)
+{
+	const vec3 c[10] = {
+		vec3(0.0f / 255.0f,   2.0f / 255.0f,  91.0f / 255.0f),
+		vec3(0.0f / 255.0f, 108.0f / 255.0f, 251.0f / 255.0f),
+		vec3(0.0f / 255.0f, 221.0f / 255.0f, 221.0f / 255.0f),
+		vec3(51.0f / 255.0f, 221.0f / 255.0f,   0.0f / 255.0f),
+		vec3(255.0f / 255.0f, 252.0f / 255.0f,   0.0f / 255.0f),
+		vec3(255.0f / 255.0f, 180.0f / 255.0f,   0.0f / 255.0f),
+		vec3(255.0f / 255.0f, 104.0f / 255.0f,   0.0f / 255.0f),
+		vec3(226.0f / 255.0f,  22.0f / 255.0f,   0.0f / 255.0f),
+		vec3(191.0f / 255.0f,   0.0f / 255.0f,  83.0f / 255.0f),
+		vec3(145.0f / 255.0f,   0.0f / 255.0f,  65.0f / 255.0f)
+	};
+
+	const float s = t * 10.0f;
+
+	const int cur = int(s) <= 9 ? int(s) : 9;
+	const int prv = cur >= 1 ? cur - 1 : 0;
+	const int nxt = cur < 9 ? cur + 1 : 9;
+
+	const float blur = 0.8f;
+
+	const float wc = smoothstep(float(cur) - blur, float(cur) + blur, s) * (1.0f - smoothstep(float(cur + 1) - blur, float(cur + 1) + blur, s));
+	const float wp = 1.0f - smoothstep(float(cur) - blur, float(cur) + blur, s);
+	const float wn = smoothstep(float(cur + 1) - blur, float(cur + 1) + blur, s);
+
+	const vec3 r = wc * c[cur] + wp * c[prv] + wn * c[nxt];
+	return vec3(clamp(r.x, 0.0f, 1.0f), clamp(r.y, 0.0f, 1.0f), clamp(r.z, 0.0f, 1.0f));
+}

assets/shaders/RayTracing.rgen

@@ -1,6 +1,10 @@
 #version 460
+#extension GL_ARB_gpu_shader_int64 : require
+#extension GL_ARB_shader_clock : require
 #extension GL_GOOGLE_include_directive : require
 #extension GL_EXT_ray_tracing : require
+
+#include "Heatmap.glsl"
 #include "Random.glsl"
 #include "RayPayload.glsl"
 #include "UniformBufferObject.glsl"
@@ -12,8 +16,11 @@ layout(binding = 3) readonly uniform UniformBufferObjectStruct { UniformBufferOb
 
 layout(location = 0) rayPayloadEXT RayPayload Ray;
 
+
 void main() 
 {
+	const uint64_t clock = Camera.ShowHeatmap ? clockARB() : 0;
+
 	// Initialise separate random seeds for the pixel and the rays.
 	// - pixel: we want the same random seed for each pixel to get a homogeneous anti-aliasing.
 	// - ray: we want a noisy random seed, different for each pixel.
@@ -79,10 +86,16 @@ void main()
 
 	pixelColor = accumulatedColor / Camera.TotalNumberOfSamples;
 
-	if (Camera.GammaCorrection)
+	// Apply raytracing-in-one-weekend gamma correction.
+	pixelColor = sqrt(pixelColor);
+
+	if (Camera.ShowHeatmap)
 	{
-		// Apply raytracing-in-one-weekend gamma correction.
-		pixelColor = sqrt(pixelColor);
+		const uint64_t deltaTime = clockARB() - clock;
+		const float heatmapScale = 1000000.0f * Camera.HeatmapScale * Camera.HeatmapScale;
+		const float deltaTimeScaled = clamp(float(deltaTime) / heatmapScale, 0.0f, 1.0f);
+
+		pixelColor = heatmap(deltaTimeScaled);
 	}
 
 	imageStore(AccumulationImage, ivec2(gl_LaunchIDEXT.xy), vec4(accumulatedColor, 0));

assets/shaders/UniformBufferObject.glsl

@@ -7,10 +7,11 @@ struct UniformBufferObject
 	mat4 ProjectionInverse;
 	float Aperture;
 	float FocusDistance;
+	float HeatmapScale;
 	uint TotalNumberOfSamples;
 	uint NumberOfSamples;
 	uint NumberOfBounces;
 	uint RandomSeed;
-	bool GammaCorrection;
 	bool HasSky;
+	bool ShowHeatmap;
 };

src/Assets/UniformBuffer.hpp

@@ -22,12 +22,13 @@ namespace Assets
 		glm::mat4 ProjectionInverse;
 		float Aperture;
 		float FocusDistance;
+		float HeatmapScale;
 		uint32_t TotalNumberOfSamples;
 		uint32_t NumberOfSamples;
 		uint32_t NumberOfBounces;
 		uint32_t RandomSeed;
-		uint32_t GammaCorrection; // bool
 		uint32_t HasSky; // bool
+		uint32_t ShowHeatmap; // bool
 	};
 
 	class UniformBuffer

src/ModelViewController.cpp

@@ -13,6 +13,9 @@ void ModelViewController::Reset(const glm::mat4& modelView)
 	modelRotX_ = 0;
 	modelRotY_ = 0;
 
+	mouseLeftPressed_ = false;
+	mouseRightPressed_ = false;
+
 	UpdateVectors();
 }
 

src/RayTracer.cpp

@@ -51,8 +51,9 @@ Assets::UniformBufferObject RayTracer::GetUniformBufferObject(const VkExtent2D e
 	ubo.NumberOfSamples = numberOfSamples_;
 	ubo.NumberOfBounces = userSettings_.NumberOfBounces;
 	ubo.RandomSeed = 1;
-	ubo.GammaCorrection = userSettings_.GammaCorrection;
 	ubo.HasSky = init.HasSky;
+	ubo.ShowHeatmap = userSettings_.ShowHeatmap;
+	ubo.HeatmapScale = userSettings_.HeatmapScale;
 
 	return ubo;
 }
@@ -63,9 +64,17 @@ void RayTracer::SetPhysicalDevice(
 	VkPhysicalDeviceFeatures& deviceFeatures, 
 	void* nextDeviceFeatures)
 {
+	// Required extensions.
+	requiredExtensions.insert(requiredExtensions.end(),
+		{
+			// VK_KHR_SHADER_CLOCK is required for heatmap
+			VK_KHR_SHADER_CLOCK_EXTENSION_NAME
+		});
+
 	// Opt-in into mandatory device features.
 	deviceFeatures.fillModeNonSolid = true;
 	deviceFeatures.samplerAnisotropy = true;
+	deviceFeatures.shaderInt64 = true;
 
 	Application::SetPhysicalDevice(physicalDevice, requiredExtensions, deviceFeatures, nextDeviceFeatures);
 }
@@ -187,6 +196,7 @@ void RayTracer::OnKey(int key, int scancode, int action, int mods)
 			case GLFW_KEY_F1: userSettings_.ShowSettings = !userSettings_.ShowSettings; break;
 			case GLFW_KEY_F2: userSettings_.ShowOverlay = !userSettings_.ShowOverlay; break;
 			case GLFW_KEY_R: userSettings_.IsRayTraced = !userSettings_.IsRayTraced; break;
+			case GLFW_KEY_H: userSettings_.ShowHeatmap = !userSettings_.ShowHeatmap; break;
 			case GLFW_KEY_P: isWireFrame_ = !isWireFrame_; break;
 			default: break;
 			}
@@ -261,7 +271,6 @@ void RayTracer::LoadScene(const uint32_t sceneIndex)
 	userSettings_.FieldOfView = cameraInitialSate_.FieldOfView;
 	userSettings_.Aperture = cameraInitialSate_.Aperture;
 	userSettings_.FocusDistance = cameraInitialSate_.FocusDistance;
-	userSettings_.GammaCorrection = cameraInitialSate_.GammaCorrection;
 
 	modelViewController_.Reset(cameraInitialSate_.ModelView);
 

src/UserInterface.cpp

@@ -181,29 +181,22 @@ void UserInterface::DrawSettings()
 
 		ImGui::Text("Help");
 		ImGui::Separator();
-		ImGui::BulletText("Press F1 to toggle Settings.");
-		ImGui::BulletText("Press F2 to toggle Statistics.");
-		ImGui::BulletText("Press R to toggle ray tracing.");
-		ImGui::NewLine();
-
-		ImGui::Text("Controls");
-		ImGui::Separator();
+		ImGui::BulletText("F1: toggle Settings.");
+		ImGui::BulletText("F2: toggle Statistics.");
 		ImGui::BulletText(
-			"Press %c%c%c%c/SHIFT/CTRL to move camera.", 
+			"%c%c%c%c/SHIFT/CTRL: move camera.", 
 			std::toupper(window.GetKeyName(GLFW_KEY_W, 0)[0]),
 			std::toupper(window.GetKeyName(GLFW_KEY_A, 0)[0]),
 			std::toupper(window.GetKeyName(GLFW_KEY_S, 0)[0]),
 			std::toupper(window.GetKeyName(GLFW_KEY_D, 0)[0]));
-		ImGui::BulletText("Click left mouse to rotate camera.");
-		ImGui::BulletText("Click right mouse to rotate scene.");
+		ImGui::BulletText("L/R Mouse: rotate camera/scene.");
 		ImGui::NewLine();
 
 		ImGui::Text("Scene");
 		ImGui::Separator();
 		ImGui::PushItemWidth(-1);
 		ImGui::Combo("", &Settings().SceneIndex, scenes.data(), static_cast<int>(scenes.size()));
 		ImGui::PopItemWidth();
-		ImGui::Checkbox("Show statistics overlay", &Settings().ShowOverlay);
 		ImGui::NewLine();
 
 		ImGui::Text("Ray Tracing");
@@ -221,7 +214,12 @@ void UserInterface::DrawSettings()
 		ImGui::SliderFloat("FoV", &Settings().FieldOfView, UserSettings::FieldOfViewMinValue, UserSettings::FieldOfViewMaxValue, "%.0f");
 		ImGui::SliderFloat("Aperture", &Settings().Aperture, 0.0f, 1.0f, "%.2f");
 		ImGui::SliderFloat("Focus", &Settings().FocusDistance, 0.1f, 20.0f, "%.1f");
-		ImGui::Checkbox("Apply gamma correction", &Settings().GammaCorrection);
+		ImGui::NewLine();
+
+		ImGui::Text("Profiler");
+		ImGui::Separator();
+		ImGui::Checkbox("Show heatmap", &Settings().ShowHeatmap);
+		ImGui::SliderFloat("Scaling", &Settings().HeatmapScale, 0.01f, 10.0f, "%.2f", 2);
 		ImGui::NewLine();
 	}
 	ImGui::End();

src/UserSettings.hpp

@@ -23,7 +23,10 @@ struct UserSettings final
 	float FieldOfView;
 	float Aperture;
 	float FocusDistance;
-	bool GammaCorrection;
+
+	// Profiler
+	bool ShowHeatmap;
+	float HeatmapScale;
 
 	// UI
 	bool ShowSettings;

src/main.cpp

@@ -108,6 +108,9 @@ namespace
 		userSettings.ShowSettings = !options.Benchmark;
 		userSettings.ShowOverlay = true;
 
+		userSettings.ShowHeatmap = false;
+		userSettings.HeatmapScale = 1.5f;
+
 		return userSettings;
 	}