Changed roughness -> alpha routine, fixed untextured models

README.md

@@ -18,10 +18,9 @@ glTF files specified on the command line are loaded and rendered.
 "Open With" or dragging and dropping a glTF file over the executable works on Windows too.
 
 There are restrictions about which glTF files can be opened.
-- All geometries must have tangents.
+- All primitives using normal maps must have tangents.
 - Only one set of texture coordinates is supported.
-- There must be at least one texture.
 - All primitives must have a material.
-- All materials must have a base color texture.
+- Vertex colors are unsupported.
 
-Many models from https://github.com/KhronosGroup/glTF-Sample-Models/, such as the Sponza, Damaged Helmet, and Lantern, fulfill these restrictions.
+Many models from https://github.com/KhronosGroup/glTF-Sample-Models/, such as the Sponza, Damaged Helmet (if tangents are added), and Lantern, fulfill these restrictions.

shaders/triangle.rchit

@@ -54,9 +54,7 @@ layout(location = 0) rayPayloadInEXT RayPayload payload;
 hitAttributeEXT vec2 baryCoord;
 
 float roughnessToAlpha(float roughness) {
-	roughness = max(roughness, 1e-3);
-	float x = log(roughness);
-	return 1.62142f + 0.819955f * x + 0.1734f * x * x + 0.0171201f * x * x * x + 0.000640711f * x * x * x * x;
+	return ((9.12793 * roughness - 16.3381) * roughness + 9.84534) * roughness + 0.013222;
 }
 
 vec3 sampleLight(vec3 hitPoint, vec3 objectHitNormal, float alpha) {
@@ -150,7 +148,7 @@ void main() {
 
 	vec3 hitPoint = gl_WorldRayOriginEXT + gl_HitTEXT * gl_WorldRayDirectionEXT;
 
-	vec3 instanceColor = material.albedoFactor; 
+	vec3 instanceColor = material.albedoScale.xyz; 
 	if(albedoTexIndex != 65535)
 		instanceColor *= texture(textures[nonuniformEXT(albedoTexIndex)], texCoords).rgb;
 
@@ -159,17 +157,21 @@ void main() {
 	if(normalTexIndex != 65535 && abs(material.normalMapFactor) > 0.001f) {
 		mat3 tbn = mat3(tangent, cross(normal, tangent) * tangentData.w, normal);
 		vec3 normalMap = (texture(textures[nonuniformEXT(normalTexIndex)], texCoords).rgb * 2.0f - 1.0f) * material.normalMapFactor;
-		objectHitNormal = normalize((tbn * normalMap)) * vec3(1.0f, -1.0f, 1.0f);
+		objectHitNormal = normalize((tbn * normalMap));
 	}
+	objectHitNormal *= vec3(1.0f, -1.0f, 1.0f);
 
 	vec3 incomingRadiance = vec3(0.0f);
 
 	if(emissiveTexIndex != 65535)
-		incomingRadiance += texture(textures[nonuniformEXT(emissiveTexIndex)], texCoords).rgb * material.emissiveFactor.rgb * 500.0f;
+		incomingRadiance += texture(textures[nonuniformEXT(emissiveTexIndex)], texCoords).rgb * material.emissiveFactor.rgb * 200.0f;
 
 	float roughness = material.roughnessFactor;
-	if(metalRoughTexIndex != 65535)
-		roughness *= texture(textures[nonuniformEXT(metalRoughTexIndex)], texCoords).b;
+	float metal = material.metallicFactor;
+	if(metalRoughTexIndex != 65535) {
+		roughness *= texture(textures[nonuniformEXT(metalRoughTexIndex)], texCoords).g;
+
+	}
 
 	float alpha = roughnessToAlpha(roughness);
 
@@ -190,8 +192,12 @@ void main() {
 		else {
 			payload.rayThroughput /= 1.0f - russianRouletteWeight;
 		}
+		vec3 offset = 0.01f * objectHitNormal;
 
-		traceRayEXT(tlasStructure, gl_RayFlagsNoneEXT, 0xFF, 0, 0, 0, hitPoint + 0.01f * objectHitNormal, 0, sampleDir, 999999999.0f, 0);
+		if(dot(sampleDir, objectHitNormal) < 0.0f) {
+			offset = 0.01f * normalize(-sampleDir);
+		}
+		traceRayEXT(tlasStructure, gl_RayFlagsNoneEXT, 0xFF, 0, 0, 0, hitPoint + offset, 0, sampleDir, 999999999.0f, 0);
 
 		incomingRadiance += payload.color.rgb * max(payload.color.a, 0.0f);
 	}

src/main.cpp

@@ -9,7 +9,7 @@ int main(int argc, const char** argv) {
 	verifyResult(volkInitialize());
 	glfwInit();
 
-	RayTracingDevice device = RayTracingDevice(640, 480, true);
+	RayTracingDevice device = RayTracingDevice(true);
 
 	std::vector<std::string_view> gltfFilenames;
 	gltfFilenames.reserve(argc - 1);
@@ -19,20 +19,20 @@ int main(int argc, const char** argv) {
 	}
 
 	std::vector<Sphere> spheres = {
-		/*{ .position = { -8.3395f, -0.76978f, -2.3374f, }, .radius = 0.5f, .color = { 0.8f, 0.6f, 0.6f, 500.0f } },
+		{ .position = { -8.3395f, -0.76978f, -2.3374f, }, .radius = 0.5f, .color = { 0.8f, 0.6f, 0.6f, 500.0f } },
 		{ .position = { 8.9656f, -0.76978f, -2.3374f }, .radius = 0.5f, .color = { 0.4f, 0.7f, 0.6f, 500.0f } },
-		{ .position = { -8.73348522f, -3.92734623f, -2.85059690f }, .radius = 0.5f, .color = { 0.8f, 0.5f, 0.4f, 500.0f } }*/
+		{ .position = { -8.73348522f, -3.92734623f, -2.85059690f }, .radius = 0.5f, .color = { 0.8f, 0.5f, 0.4f, 500.0f } },
 		{ .position = { 0.3f, -1.76978f, -2.3374f }, .radius = 0.5f, .color = { 0.7f, 0.7f, 0.7f, 500.0f } }
 	};
 
 	MemoryAllocator allocator = MemoryAllocator(device);
 	OneTimeDispatcher dispatcher = OneTimeDispatcher(device);
 	ModelLoader loader = ModelLoader(device, allocator, dispatcher, gltfFilenames);
-	AccelerationStructureBuilder builder = AccelerationStructureBuilder(
-		device, allocator, dispatcher, loader,
-		spheres, 0, 1);
+	AccelerationStructureBuilder builder =
+		AccelerationStructureBuilder(device, allocator, dispatcher, loader, spheres, 0, 1);
 	PipelineBuilder pipelineBuilder =
-		PipelineBuilder(device, allocator, dispatcher, loader.textureDescriptorSetLayout(), 8);
+		PipelineBuilder(device, allocator, dispatcher,
+						loader.textures().empty() ? VK_NULL_HANDLE : loader.textureDescriptorSetLayout(), 8);
 
 	TriangleMeshRaytracer raytracer = TriangleMeshRaytracer(device, allocator, loader, pipelineBuilder, builder);
 

src/util/ModelLoader.cpp

@@ -563,24 +563,26 @@ ModelLoader::ModelLoader(RayTracingDevice& device, MemoryAllocator& allocator, O
 	vkDestroyBuffer(m_device.device(), m_indexStagingBuffer, nullptr);
 	vkDestroyBuffer(m_device.device(), m_imageStagingBuffer, nullptr);
 
-	std::vector<VkDescriptorImageInfo> textureImageInfos;
+	if (m_textures.size()) {
+		std::vector<VkDescriptorImageInfo> textureImageInfos;
 
-	textureImageInfos.reserve(m_textures.size());
+		textureImageInfos.reserve(m_textures.size());
 
-	for (auto& texture : m_textures) {
-		textureImageInfos.push_back({ .sampler = texture.sampler,
-									  .imageView = texture.view,
-									  .imageLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL });
-	}
+		for (auto& texture : m_textures) {
+			textureImageInfos.push_back({ .sampler = texture.sampler,
+										  .imageView = texture.view,
+										  .imageLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL });
+		}
 
-	VkWriteDescriptorSet setWrite = { .sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET,
-									  .dstSet = m_textureDescriptorSet,
-									  .dstBinding = 0,
-									  .dstArrayElement = 0,
-									  .descriptorCount = static_cast<uint32_t>(m_textures.size()),
-									  .descriptorType = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER,
-									  .pImageInfo = textureImageInfos.data() };
-	vkUpdateDescriptorSets(m_device.device(), 1, &setWrite, 0, nullptr);
+		VkWriteDescriptorSet setWrite = { .sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET,
+										  .dstSet = m_textureDescriptorSet,
+										  .dstBinding = 0,
+										  .dstArrayElement = 0,
+										  .descriptorCount = static_cast<uint32_t>(m_textures.size()),
+										  .descriptorType = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER,
+										  .pImageInfo = textureImageInfos.data() };
+		vkUpdateDescriptorSets(m_device.device(), 1, &setWrite, 0, nullptr);
+	}
 }
 
 ModelLoader::~ModelLoader() {
@@ -601,8 +603,10 @@ ModelLoader::~ModelLoader() {
 	}
 	vkDestroySampler(m_device.device(), m_fallbackSampler, nullptr);
 
-	vkDestroyDescriptorPool(m_device.device(), m_textureDescriptorPool, nullptr);
-	vkDestroyDescriptorSetLayout(m_device.device(), m_textureDescriptorSetLayout, nullptr);
+	if (m_textures.size()) {
+		vkDestroyDescriptorPool(m_device.device(), m_textureDescriptorPool, nullptr);
+		vkDestroyDescriptorSetLayout(m_device.device(), m_textureDescriptorSetLayout, nullptr);
+	}
 }
 
 void ModelLoader::addScene(cgltf_data* data, cgltf_scene* scene) {
@@ -981,7 +985,7 @@ void ModelLoader::addMaterial(cgltf_data* data, cgltf_material* material) {
 											 data->textures + m_globalTextureIndexOffset;
 		}
 		if (material->pbr_metallic_roughness.metallic_roughness_texture.texture) {
-			newMaterial.metallicRoughnessTextureIndex = material->pbr_metallic_roughness.base_color_texture.texture -
+			newMaterial.metallicRoughnessTextureIndex = material->pbr_metallic_roughness.metallic_roughness_texture.texture -
 														data->textures + m_globalTextureIndexOffset;
 		}
 

src/util/PipelineBuilder.cpp

@@ -82,7 +82,7 @@ PipelineBuilder::PipelineBuilder(RayTracingDevice& device, MemoryAllocator& allo
 	VkDescriptorSetLayout layouts[3] = { m_imageDescriptorSetLayout, m_generalDescriptorSetLayout, textureSetLayout };
 
 	VkPipelineLayoutCreateInfo pipelineLayoutCreateInfo = { .sType = VK_STRUCTURE_TYPE_PIPELINE_LAYOUT_CREATE_INFO,
-															.setLayoutCount = 3,
+															.setLayoutCount = textureSetLayout == VK_NULL_HANDLE ? 2U : 3U,
 															.pSetLayouts = layouts,
 															.pushConstantRangeCount = 1,
 															.pPushConstantRanges = &constantRange };