Made small ray tracer with a sphere to test fragment shading and uniform buffers

CMakeLists.txt

@@ -51,7 +51,7 @@ add_dependencies(pleascach shaders)
 if(UNIX)
 	add_custom_command(
 		TARGET shaders POST_BUILD
-		COMMAND cp -r
+		COMMAND cmake -E copy_directory
 		"$<TARGET_PROPERTY:pleascach,SOURCE_DIR>/assets"
 		"$<TARGET_PROPERTY:pleascach,BINARY_DIR>/assets")
 else()

Renderer/Renderer.cpp

@@ -186,7 +186,7 @@ Renderer::Renderer(Window& win) : win(win) {
 
 	std::vector<Shader> shaders = {
 		{ dev, "assets/shaders/basic.vert.spv", vk::ShaderStageFlagBits::eVertex },
-		{ dev, "assets/shaders/basic.frag.spv", vk::ShaderStageFlagBits::eFragment },
+		{ dev, "assets/shaders/trace.frag.spv", vk::ShaderStageFlagBits::eFragment },
 	};
 
 	std::vector<vk::DescriptorSetLayoutBinding> bindings = {
@@ -265,11 +265,14 @@ void Renderer::draw() {
 	command_buffer->bind(*vertex_buffer);
 	command_buffer->bind(pipeline->layout, pipeline->desc_set);
 
-	const auto p = glm::perspective(glm::radians(90.0f), static_cast<float>(swapchain->extent.width) / static_cast<float>(swapchain->extent.height), 0.01f, 50.0f);
+	auto sz = win.getDimensions();
+
+	const auto p = glm::perspective(glm::radians(90.0f), static_cast<float>(sz.width) / static_cast<float>(sz.height), 0.01f, 50.0f);
 
 	uniform_buffer->upload(UniformData{
 		//.mvp = p * glm::rotate(glm::mat4(1.0), glm::radians(static_cast<float>(frame)), glm::vec3(1.0, 1.0, 1.0)),
-		.time = static_cast<float>(frame),
+		.time = static_cast<float>(frame) * 0.0167f,
+		.aspect_ratio = static_cast<float>(sz.width)/static_cast<float>(sz.height),
 	});
 
 

Renderer/UniformBuffer.hpp

@@ -12,6 +12,7 @@
 struct UniformData {
 	glm::mat4 mvp;
 	float time;
+	float aspect_ratio;
 };
 
 struct UniformBuffer {

assets/shaders/trace.frag

@@ -0,0 +1,62 @@
+#version 460 core
+
+layout (location = 0) in vec2 texCoord;
+layout (location = 0) out vec4 FragColor;
+
+layout (set = 0, binding = 0) uniform Matrices {
+	mat4 mpv;
+	float time;
+	float aspect_ratio;
+};
+
+/* 4-float alignment in memory*/
+struct Ray {
+	vec3 orig;
+	float min;
+	vec3 dir;
+	float max;
+};
+
+vec3 ray_color(vec3 ray) {
+	float a = 0.5 * (ray.y+1.0);
+
+	return vec3(1.0-a) + a*vec3(0.5, 0.7, 1.0);
+}
+
+
+/* returns float of where you hit, or -1.0 */
+float sphere(vec3 center, float r, Ray ray) {
+	vec3 p = ray.orig-center;
+	float a = dot(ray.dir, ray.dir);
+	float half_b = dot(p, ray.dir);
+	float c = dot(p, p) - r*r;
+	float discr = half_b*half_b - a*c;
+
+	if(discr < 0.0)
+		return -1.0;
+	
+	return -half_b-sqrt(discr)/a;
+} 
+
+void main() {
+	vec2 pixel = texCoord*2.0-1.0;
+	Ray ray;
+	ray.orig = vec3(0.0);
+	ray.min = 0.1;
+	ray.max = 10000.0;
+	float fov = radians(90);
+	ray.dir = normalize(vec3(pixel.x * aspect_ratio, pixel.y, tan(fov/2.0)));
+
+	vec3 sphere_center = vec3(0.0, 0.0, 1.0);
+
+	float d = sphere(sphere_center, 0.5, ray);
+
+	if(d < 0.0) {
+		FragColor = vec4(0.0);
+		return;
+	}
+
+	vec3 n = normalize(ray.dir*d-sphere_center);
+	FragColor = vec4((n+vec3(1.0)) / 2.0, 1.0);
+
+}