plumageRender/homework/homework1/homework1.cpp

/*
* Vulkan Example - glTF scene loading and rendering
*
* Copyright (C) 2020-2022 by Sascha Willems - www.saschawillems.de
*
* This code is licensed under the MIT license (MIT) (http://opensource.org/licenses/MIT)
*/

/*
 * Shows how to load and display a simple scene from a glTF file
 * Note that this isn't a complete glTF loader and only basic functions are shown here
 * This means no complex materials, no animations, no skins, etc.
 * For details on how glTF 2.0 works, see the official spec at https://github.com/KhronosGroup/glTF/tree/master/specification/2.0
 *
 * Other samples will load models using a dedicated model loader with more features (see base/VulkanglTFModel.hpp)
 *
 * If you are looking for a complete glTF implementation, check out https://github.com/SaschaWillems/Vulkan-glTF-PBR/
 */


#include "homework1.h"



	/*
		glTF loading functions

		The following functions take a glTF input model loaded via tinyglTF and convert all required data into our own structure
	*/

	void VulkanglTFModel::loadImages(tinygltf::Model& input)
	{
		// Images can be stored inside the glTF (which is the case for the sample model), so instead of directly
		// loading them from disk, we fetch them from the glTF loader and upload the buffers
		images.resize(input.images.size());
		for (size_t i = 0; i < input.images.size(); i++) {
			tinygltf::Image& glTFImage = input.images[i];
			// Get the image data from the glTF loader
			unsigned char* buffer = nullptr;
			VkDeviceSize bufferSize = 0;
			bool deleteBuffer = false;
			// We convert RGB-only images to RGBA, as most devices don't support RGB-formats in Vulkan
			if (glTFImage.component == 3) {
				bufferSize = glTFImage.width * glTFImage.height * 4;
				buffer = new unsigned char[bufferSize];
				unsigned char* rgba = buffer;
				unsigned char* rgb = &glTFImage.image[0];
				for (size_t i = 0; i < glTFImage.width * glTFImage.height; ++i) {
					memcpy(rgba, rgb, sizeof(unsigned char) * 3);
					rgba += 4;
					rgb += 3;
				}
				deleteBuffer = true;
			}
			else {
				buffer = &glTFImage.image[0];
				bufferSize = glTFImage.image.size();
			}
			// Load texture from image buffer
			images[i].texture.fromBuffer(buffer, bufferSize, VK_FORMAT_R8G8B8A8_UNORM, glTFImage.width, glTFImage.height, vulkanDevice, copyQueue);
			if (deleteBuffer) {
				delete[] buffer;
			}
		}
	}

	void VulkanglTFModel::loadTextures(tinygltf::Model& input)
	{
		textures.resize(input.textures.size());
		for (size_t i = 0; i < input.textures.size(); i++) {
			textures[i].imageIndex = input.textures[i].source;
		}
	}

	void VulkanglTFModel::loadMaterials(tinygltf::Model& input)
	{
		materials.resize(input.materials.size());
		for (size_t i = 0; i < input.materials.size(); i++) {
			// We only read the most basic properties required for our sample
			tinygltf::Material glTFMaterial = input.materials[i];
			// Get the base color factor
			if (glTFMaterial.values.find("baseColorFactor") != glTFMaterial.values.end()) {
				materials[i].baseColorFactor = glm::make_vec4(glTFMaterial.values["baseColorFactor"].ColorFactor().data());
			}
			// Get base color texture index
			if (glTFMaterial.values.find("baseColorTexture") != glTFMaterial.values.end()) {
				materials[i].baseColorTextureIndex = glTFMaterial.values["baseColorTexture"].TextureIndex();
			}
			if (glTFMaterial.values.find("metallicRoughnessTexture") != glTFMaterial.values.end()) {
				materials[i].matalicRoughTextureIndex = glTFMaterial.values["metallicRoughnessTexture"].TextureIndex();
			}
			if (glTFMaterial.additionalValues.find("normalTexture") != glTFMaterial.additionalValues.end())
			{
				materials[i].normalMapTextureIndex = glTFMaterial.additionalValues["normalTexture"].TextureIndex();
			}
			if (glTFMaterial.emissiveTexture.index != -1)
			{
				materials[i].emissiveTextureIndex = glTFMaterial.emissiveTexture.index;
			}
			if (glTFMaterial.emissiveFactor.size() == 3)
			{
				materials[i].materialData.values.emissiveFactor = glm::make_vec3(glTFMaterial.emissiveFactor.data());
			}

			if (glTFMaterial.values.find("baseColorFactor") != glTFMaterial.values.end())
			{
				materials[i].materialData.values.baseColorFactor = glm::make_vec4(glTFMaterial.values["baseColorFactor"].ColorFactor().data());
			}
		}
	}
	
	
	//animation loader
	void VulkanglTFModel::loadAnimations(tinygltf::Model& input)
	{
		animations.resize(input.animations.size());

		for (size_t i = 0; i < input.animations.size(); i++)
		{
			tinygltf::Animation glTFAnimation = input.animations[i];
			animations[i].name = glTFAnimation.name;

			// Samplers
			animations[i].samplers.resize(glTFAnimation.samplers.size());
			for (size_t j = 0; j < glTFAnimation.samplers.size(); j++)
			{
				tinygltf::AnimationSampler glTFSampler = glTFAnimation.samplers[j];
				AnimationSampler& dstSampler = animations[i].samplers[j];
				dstSampler.interpolation = glTFSampler.interpolation;

				// Read sampler keyframe input time values
				{
					const tinygltf::Accessor& accessor = input.accessors[glTFSampler.input];
					const tinygltf::BufferView& bufferView = input.bufferViews[accessor.bufferView];
					const tinygltf::Buffer& buffer = input.buffers[bufferView.buffer];
					const void* dataPtr = &buffer.data[accessor.byteOffset + bufferView.byteOffset];
					const float* buf = static_cast<const float*>(dataPtr);
					for (size_t index = 0; index < accessor.count; index++)
					{
						dstSampler.inputs.push_back(buf[index]);
					}
					// Adjust animation's start and end times
					for (auto input : animations[i].samplers[j].inputs)
					{
						if (input < animations[i].start)
						{
							animations[i].start = input;
						};
						if (input > animations[i].end)
						{
							animations[i].end = input;
						}
					}
				}

				// Read sampler keyframe output translate/rotate/scale values
				{
					const tinygltf::Accessor& accessor = input.accessors[glTFSampler.output];
					const tinygltf::BufferView& bufferView = input.bufferViews[accessor.bufferView];
					const tinygltf::Buffer& buffer = input.buffers[bufferView.buffer];
					const void* dataPtr = &buffer.data[accessor.byteOffset + bufferView.byteOffset];
					switch (accessor.type)
					{
					case TINYGLTF_TYPE_VEC3: {
						const glm::vec3* buf = static_cast<const glm::vec3*>(dataPtr);
						for (size_t index = 0; index < accessor.count; index++)
						{
							dstSampler.outputsVec4.push_back(glm::vec4(buf[index], 0.0f));
						}
						break;
					}
					case TINYGLTF_TYPE_VEC4: {
						const glm::vec4* buf = static_cast<const glm::vec4*>(dataPtr);
						for (size_t index = 0; index < accessor.count; index++)
						{
							dstSampler.outputsVec4.push_back(buf[index]);
						}
						break;
					}
					default: {
						std::cout << "unknown type" << std::endl;
						break;
					}
					}
				}
			}

			// Channels
			animations[i].channels.resize(glTFAnimation.channels.size());
			for (size_t j = 0; j < glTFAnimation.channels.size(); j++)
			{
				tinygltf::AnimationChannel glTFChannel = glTFAnimation.channels[j];
				AnimationChannel& dstChannel = animations[i].channels[j];
				dstChannel.path = glTFChannel.target_path;
				dstChannel.samplerIndex = glTFChannel.sampler;
				dstChannel.node = nodeFromIndex(glTFChannel.target_node);
			}
		}

		
	}

	// load skins from glTF model
	void VulkanglTFModel::loadSkins(tinygltf::Model& input)
	{
		
		skins.resize(input.skins.size());
		if (skins.size() > 0)
		{
			for (size_t i = 0; i < input.skins.size(); i++)
				{
					tinygltf::Skin glTFSkin = input.skins[i];

					skins[i].name = glTFSkin.name;
					//follow the tree structure,find the root node of skeleton by index
					skins[i].skeletonRoot = nodeFromIndex(glTFSkin.skeleton);

					//join nodes
					for (int jointIndex : glTFSkin.joints)
						{
							Node* node = nodeFromIndex(jointIndex);
							if (node)
							{
								skins[i].joints.push_back(node);
							}
						}
					//get the inverse bind matrices
					if (glTFSkin.inverseBindMatrices > -1)
						{
							const tinygltf::Accessor& accessor = input.accessors[glTFSkin.inverseBindMatrices];
							const tinygltf::BufferView& bufferview = input.bufferViews[accessor.bufferView];
							const tinygltf::Buffer& buffer = input.buffers[bufferview.buffer];
							skins[i].inverseBindMatrices.resize(accessor.count);
							memcpy(skins[i].inverseBindMatrices.data(), &buffer.data[accessor.byteOffset + bufferview.byteOffset], accessor.count * sizeof(glm::mat4));

							//create a host visible shader buffer to store inverse bind matrices for this skin
							VK_CHECK_RESULT(
								vulkanDevice->createBuffer(
								VK_BUFFER_USAGE_STORAGE_BUFFER_BIT,
								VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT,
								&skins[i].ssbo,
								sizeof(glm::mat4) * skins[i].inverseBindMatrices.size(),
								skins[i].inverseBindMatrices.data()));
							VK_CHECK_RESULT(skins[i].ssbo.map());
						}
				}

		}
		


	}

	//glTF nodes loading helper function
	//rewrite node loader,simplify logic
	//Search node from parent to children by index
	VulkanglTFModel::Node* VulkanglTFModel::findNode(Node* parent, uint32_t index)
	{
		Node* nodeFound = nullptr;
		if (parent->index == index)
		{
			return parent;
		}
		for (auto& child : parent->children)
		{
			nodeFound = findNode(child, index);
			if (nodeFound)
			{
				break;
			}
		}
		return nodeFound;
	}	//iterate vector of nodes to check weather nodes exist or not
	VulkanglTFModel::Node* VulkanglTFModel::nodeFromIndex(uint32_t index)
	{
		Node* nodeFound = nullptr;
		for (auto& node : nodes)
		{
			nodeFound = findNode(node, index);
			if (nodeFound)
			{
				break;
			}
		}
		return nodeFound;
	}


	//node loader
	void VulkanglTFModel::loadNode(const tinygltf::Node& inputNode, const tinygltf::Model& input, VulkanglTFModel::Node* parent, uint32_t nodeIndex, std::vector<uint32_t>& indexBuffer, std::vector<VulkanglTFModel::Vertex>& vertexBuffer)
	{
		VulkanglTFModel::Node* node = new VulkanglTFModel::Node{};
		node->parent = parent;
		node->matrix = glm::mat4(1.0f);
		node->index = nodeIndex;
		node->skin = inputNode.skin;

		//get distributions of node
		if (inputNode.translation.size() == 3)
		{
			node->matrix =glm::translate(node->matrix,glm::vec3(glm::make_vec3(inputNode.translation.data())));
		}

		if (inputNode.rotation.size() == 4)
		{	//rotation is given by quaternion
			glm::quat q = glm::make_quat(inputNode.rotation.data());
			node->matrix = glm::mat4(q);
		}

		if (inputNode.scale.size() == 3)
		{
			node->matrix =glm::scale(node->matrix,glm::vec3(glm::make_vec3(inputNode.scale.data())));
		}
		
		if (inputNode.matrix.size() == 16)
		{
			node->matrix = glm::make_mat4x4(inputNode.matrix.data());
		}

		//find children of nodes if exists
		if (inputNode.children.size() > 0)
		{
			for (size_t i = 0; i < inputNode.children.size(); i++)
			{
				loadNode(input.nodes[inputNode.children[i]], input, node, inputNode.children[i], indexBuffer, vertexBuffer);
			}
			
		}
		//load meshes in nodes if exists
		if (inputNode.mesh > -1)
		{
			const tinygltf::Mesh mesh = input.meshes[inputNode.mesh];
			for (size_t i = 0; i < mesh.primitives.size(); i++)
			{
				const tinygltf::Primitive& glTFPrimmitive = mesh.primitives[i];
				uint32_t firstIndex = static_cast<uint32_t>(indexBuffer.size());
				uint32_t vertexStart = static_cast<uint32_t>(vertexBuffer.size());
				uint32_t indexCount = 0;
				//vertices 
				const float* positionBuffer = nullptr;
				const float* normalsBuffer = nullptr;
				const float* texcoordsBuffer = nullptr;
				const float* tangentsBuffer = nullptr;
				size_t vertexCount = 0;
				//skin joints
				const float* jointWeightsBuffer = nullptr;
				const uint16_t * jointIndicesBuffer = nullptr;
				
				bool hasSkin = false;
				//get buffer by index in primmitive.attributes
				{
					if (glTFPrimmitive.attributes.find("POSITION") != glTFPrimmitive.attributes.end())
					{
						const tinygltf::Accessor& accessor = input.accessors[glTFPrimmitive.attributes.find("POSITION")->second];
						const tinygltf::BufferView &view = input.bufferViews[accessor.bufferView];
						positionBuffer = reinterpret_cast<const float*> (&(input.buffers[view.buffer].data[accessor.byteOffset + view.byteOffset]));
						vertexCount = accessor.count;
					}
					if (glTFPrimmitive.attributes.find("NORMAL") != glTFPrimmitive.attributes.end())
					{
						const tinygltf::Accessor& accessor = input.accessors[glTFPrimmitive.attributes.find("NORMAL")->second];
						const tinygltf::BufferView &view = input.bufferViews[accessor.bufferView];
						normalsBuffer = reinterpret_cast<const float*> (&(input.buffers[view.buffer].data[accessor.byteOffset + view.byteOffset]));

					}
					//texture and tangent data 
					if (glTFPrimmitive.attributes.find("TEXCOORD_0") != glTFPrimmitive.attributes.end())
					{
						const tinygltf::Accessor& accessor = input.accessors[glTFPrimmitive.attributes.find("TEXCOORD_0")->second];
						const tinygltf::BufferView &view = input.bufferViews[accessor.bufferView];
						texcoordsBuffer = reinterpret_cast<const float*> (&(input.buffers[view.buffer].data[accessor.byteOffset + view.byteOffset]));

					}
					if (glTFPrimmitive.attributes.find("TANGENT") != glTFPrimmitive.attributes.end())
					{
						const tinygltf::Accessor& accessor = input.accessors[glTFPrimmitive.attributes.find("TANGENT")->second];
						const tinygltf::BufferView& view = input.bufferViews[accessor.bufferView];
						tangentsBuffer = reinterpret_cast<const float*> (&(input.buffers[view.buffer].data[accessor.byteOffset + view.byteOffset]));

					}
					//skin joints and weights data
					if (glTFPrimmitive.attributes.find("JOINTS_0") != glTFPrimmitive.attributes.end())
					{
						const tinygltf::Accessor& accessor = input.accessors[glTFPrimmitive.attributes.find("JOINTS_0")->second];
						const tinygltf::BufferView &view = input.bufferViews[accessor.bufferView];
						jointIndicesBuffer = reinterpret_cast<const uint16_t*> (&(input.buffers[view.buffer].data[accessor.byteOffset + view.byteOffset]));

					}
					if (glTFPrimmitive.attributes.find("WEIGHTS_0") != glTFPrimmitive.attributes.end())
					{
						const tinygltf::Accessor& accessor = input.accessors[glTFPrimmitive.attributes.find("WEIGHTS_0")->second];
						const tinygltf::BufferView &view = input.bufferViews[accessor.bufferView];
						jointWeightsBuffer = reinterpret_cast<const float*> (&(input.buffers[view.buffer].data[accessor.byteOffset + view.byteOffset]));

					}

					hasSkin = (jointIndicesBuffer && jointWeightsBuffer);

					for (size_t v = 0; v < vertexCount; v++)
					{
						Vertex vert{};
						vert.pos = glm::vec4(glm::make_vec3(&positionBuffer[v * 3]), 1.0f);
						vert.uv = texcoordsBuffer ? glm::make_vec2(&texcoordsBuffer[v*2]) : glm::vec3(0.0f);
						vert.normal = glm::normalize(glm::vec3(normalsBuffer ? glm::make_vec3(&normalsBuffer[v * 3]) : glm::vec3(0.0f)));
						vert.color = glm::vec3(1.0f,1.0f,nodeIndex);
						vert.tangent = tangentsBuffer ? glm::normalize(glm::make_vec3(&tangentsBuffer[v * 4])) : glm::vec3(0.0f);
						vert.jointIndices = hasSkin ? glm::vec4(glm::make_vec4(&jointIndicesBuffer[v * 4])) : glm::vec4(0.0f);
						vert.jointWeights = hasSkin ? glm::make_vec4(&jointWeightsBuffer[v * 4]) : glm::vec4(0.0f);
						vertexBuffer.push_back(vert);
					}
				}
				{
					const tinygltf::Accessor& accessor = input.accessors[glTFPrimmitive.indices];
					const tinygltf::BufferView& bufferview = input.bufferViews[accessor.bufferView];
					const tinygltf::Buffer& buffer = input.buffers[bufferview.buffer];

					indexCount += static_cast<uint32_t>(accessor.count);

					switch (accessor.componentType)
					{
					case TINYGLTF_PARAMETER_TYPE_UNSIGNED_INT: {
						const uint32_t* buf = reinterpret_cast<const uint32_t*>(&buffer.data[accessor.byteOffset + bufferview.byteOffset]);
						for (size_t index = 0; index < accessor.count; index++)
						{
							indexBuffer.push_back(buf[index] + vertexStart);
						}
						break;

					}
					case TINYGLTF_PARAMETER_TYPE_UNSIGNED_SHORT:{
						const uint16_t* buf = reinterpret_cast<const uint16_t*>(&buffer.data[accessor.byteOffset + bufferview.byteOffset]);
						for (size_t index = 0; index < accessor.count; index++)
						{
							indexBuffer.push_back(buf[index] + vertexStart);
						}
						break;
					}
					case TINYGLTF_PARAMETER_TYPE_UNSIGNED_BYTE: {
						const uint8_t* buf = reinterpret_cast<const uint8_t*>(&buffer.data[accessor.byteOffset + bufferview.byteOffset]);
						for (size_t index = 0; index < accessor.count; index++)
						{
							indexBuffer.push_back(buf[index] + vertexStart);
						}
						break;
					}
					default:
						std::cerr << "index component type" << accessor.componentType << "not supported" << std::endl;

						return;
					}
				}
				Primitive primitive{};
				primitive.firstIndex = firstIndex;
				primitive.indexCount = indexCount;
				primitive.materialIndex = glTFPrimmitive.material;
				node->mesh.primitives.push_back(primitive);
				
			}
		}
		if (parent)
		{
			parent->children.push_back(node);
		}
		else
		{
			nodes.push_back(node);
		}
	}


	/*
		vertex skinning functions
	*/
	glm::mat4 VulkanglTFModel::getNodeMatrix(VulkanglTFModel::Node* node)
	{
		glm::mat4 nodeMatrix = node->getLocalMatrix();
		VulkanglTFModel::Node* currentParent = node->parent;
		while (currentParent)
		{
			nodeMatrix = currentParent->getLocalMatrix() * nodeMatrix;
			currentParent = currentParent->parent;
		}
		return nodeMatrix;
	}
	
	void VulkanglTFModel::updateNodeMatrix(Node* node, std::vector<glm::mat4>& nodeMatrics)
	{
		if (node->skin <= -1)
		{
			nodeMatrics[node->index] = getNodeMatrix(node);
			for (auto& child : node->children)
			{
				updateNodeMatrix(child, nodeMatrics);
			}
		}
		
	}

	void VulkanglTFModel::updateJoints(VulkanglTFModel::Node* node)
	{
		if (node->skin > -1)
		{
			glm::mat4 inversTransform = glm::inverse(getNodeMatrix(node));
			Skin skin = skins[node->skin];
			size_t numJoints = (uint32_t)skin.joints.size();
			std::vector<glm::mat4> jointMatrices(numJoints);
			for (size_t i = 0; i < numJoints; i++)
			{
				jointMatrices[i] = getNodeMatrix(skin.joints[i]) * skin.inverseBindMatrices[i];
				jointMatrices[i] = inversTransform * jointMatrices[i];
			}
			skin.ssbo.copyTo(jointMatrices.data(), jointMatrices.size() * sizeof(glm::mat4));
		}
		for (auto& child : node->children)
		{
			updateJoints(child);
		}
	}

	void VulkanglTFModel::updateAnimation(float deltaTime,vks::Buffer buffer)
	{
		if (activeAnimation > static_cast<uint32_t>(animations.size()) - 1)
		{
			std::cout << "No animation with index " << activeAnimation << std::endl;
			return;
		}
		Animation& animation = animations[activeAnimation];
		animation.currentTime += deltaTime;
		if (animation.currentTime > animation.end)
		{
			animation.currentTime -= animation.end;
		}

		for (auto& channel : animation.channels)
		{
			AnimationSampler& sampler = animation.samplers[channel.samplerIndex];
			for (size_t i = 0; i < sampler.inputs.size() - 1; ++i)
			{
				if (sampler.interpolation != "LINEAR")
				{
					std::cout << "This sample only supports linear interpolations\n";
					continue;
				}

				// Get the input keyframe values for the current time stamp
				if ((animation.currentTime >= sampler.inputs[i]) && (animation.currentTime <= sampler.inputs[i + 1]))
				{
					float ratio = (animation.currentTime - sampler.inputs[i]) / (sampler.inputs[i + 1] - sampler.inputs[i]);
					if (channel.path == "translation")
					{
						channel.node->translation = glm::mix(sampler.outputsVec4[i], sampler.outputsVec4[i + 1], ratio);
						channel.node->bAnimateNode = true;
					}
					if (channel.path == "rotation")
					{
						glm::quat q1;
						q1.x = sampler.outputsVec4[i].x;
						q1.y = sampler.outputsVec4[i].y;
						q1.z = sampler.outputsVec4[i].z;
						q1.w = sampler.outputsVec4[i].w;

						glm::quat q2;
						q2.x = sampler.outputsVec4[i + 1].x;
						q2.y = sampler.outputsVec4[i + 1].y;
						q2.z = sampler.outputsVec4[i + 1].z;
						q2.w = sampler.outputsVec4[i + 1].w;

						channel.node->rotation = glm::normalize(glm::slerp(q1, q2, ratio));
						channel.node->bAnimateNode = true;
					}
					if (channel.path == "scale")
					{
						channel.node->scale = glm::mix(sampler.outputsVec4[i], sampler.outputsVec4[i + 1], ratio);
						channel.node->bAnimateNode = true;
					}
				}
			}
		}
		//if no skin in model , update node matrix to update animation stage
		std::vector<glm::mat4> nodeMatrics(nodeCount);
		for (auto& node : nodes)
		{
			//updateJoints(node);
			updateNodeMatrix(node, nodeMatrics);
		}
		buffer.copyTo(nodeMatrics.data(), nodeCount * sizeof(glm::mat4));

	}
	/*
		glTF rendering functions
	*/

	// Draw a single node including child nodes (if present)
	void VulkanglTFModel::drawNode(VkCommandBuffer commandBuffer, VkPipelineLayout pipelineLayout, VulkanglTFModel::Node node)
	{
		if (node.mesh.primitives.size() > 0) {
			// Pass the node's matrix via push constants
			// Traverse the node hierarchy to the top-most parent to get the final matrix of the current node
			glm::mat4 nodeMatrix = node.matrix;
			VulkanglTFModel::Node* currentParent = node.parent;
			while (currentParent) {
				nodeMatrix = currentParent->matrix * nodeMatrix;
				currentParent = currentParent->parent;
			}
			
			for (VulkanglTFModel::Primitive& primitive : node.mesh.primitives) {
				if (primitive.indexCount > 0) {
					// Get the texture index for this primitive
					if (textures.size() > 0)
					{
						VulkanglTFModel::Texture texture = textures[materials[primitive.materialIndex].baseColorTextureIndex];
						auto normalMap = textures[materials[primitive.materialIndex].normalMapTextureIndex];
						auto roughMetalMap = textures[materials[primitive.materialIndex].matalicRoughTextureIndex];

						if (materials[primitive.materialIndex].emissiveTextureIndex >= 0)
						{
							auto emissiveMap = textures[materials[primitive.materialIndex].emissiveTextureIndex];
							vkCmdBindDescriptorSets(commandBuffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayout, 4, 1, &images[emissiveMap.imageIndex].descriptorSet, 0, nullptr);
						}

						// Bind the descriptor for the current primitive's texture
						vkCmdBindDescriptorSets(commandBuffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayout, 1, 1, &images[texture.imageIndex].descriptorSet, 0, nullptr);
						vkCmdBindDescriptorSets(commandBuffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayout, 2, 1, &images[normalMap.imageIndex].descriptorSet, 0, nullptr);
						vkCmdBindDescriptorSets(commandBuffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayout, 3, 1, &images[roughMetalMap.imageIndex].descriptorSet, 0, nullptr);
						vkCmdBindDescriptorSets(commandBuffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayout, 5, 1, &materials[primitive.materialIndex].materialData.descriptorSet, 0, nullptr);
					}
					vkCmdDrawIndexed(commandBuffer, primitive.indexCount, 1, primitive.firstIndex, 0, 0);
				}
			}
		}
		for (auto &child : node.children) {
			drawNode(commandBuffer, pipelineLayout, *child);
		}
	}

	// Draw the glTF scene starting at the top-level-nodes
	void VulkanglTFModel::draw(VkCommandBuffer commandBuffer, VkPipelineLayout pipelineLayout)
	{
		// All vertices and indices are stored in single buffers, so we only need to bind once
		VkDeviceSize offsets[1] = { 0 };
		vkCmdBindVertexBuffers(commandBuffer, 0, 1, &vertices.buffer, offsets);
		vkCmdBindIndexBuffer(commandBuffer, indices.buffer, 0, VK_INDEX_TYPE_UINT32);
		// Render all nodes at top-level
		for (auto& node : nodes) {
			drawNode(commandBuffer, pipelineLayout, *node);
		}
	}




VulkanExample::VulkanExample():
	VulkanExampleBase(ENABLE_VALIDATION)
	{
		title = "homework1";
		camera.type = Camera::CameraType::lookat;
		camera.flipY = true;
		camera.setPosition(glm::vec3(0.0f, -0.1f, -1.0f));
		camera.setRotation(glm::vec3(0.0f, 45.0f, 0.0f));
		camera.setPerspective(60.0f, (float)width / (float)height, 0.1f, 256.0f);
	}



void VulkanExample::getEnabledFeatures()
{
	// Fill mode non solid is required for wireframe display
	if (deviceFeatures.fillModeNonSolid) {
		enabledFeatures.fillModeNonSolid = VK_TRUE;
	};
}

	void VulkanExample::buildCommandBuffers()
	{
		VkCommandBufferBeginInfo cmdBufInfo = vks::initializers::commandBufferBeginInfo();

		VkClearValue clearValues[2];
		clearValues[0].color = defaultClearColor;
		clearValues[0].color = { { 0.25f, 0.25f, 0.25f, 1.0f } };;
		clearValues[1].depthStencil = { 1.0f, 0 };

		VkRenderPassBeginInfo renderPassBeginInfo = vks::initializers::renderPassBeginInfo();
		renderPassBeginInfo.renderPass = renderPass;
		renderPassBeginInfo.renderArea.offset.x = 0;
		renderPassBeginInfo.renderArea.offset.y = 0;
		renderPassBeginInfo.renderArea.extent.width = width;
		renderPassBeginInfo.renderArea.extent.height = height;
		renderPassBeginInfo.clearValueCount = 2;
		renderPassBeginInfo.pClearValues = clearValues;

		const VkViewport viewport = vks::initializers::viewport((float)width, (float)height, 0.0f, 1.0f);
		const VkRect2D scissor = vks::initializers::rect2D(width, height, 0, 0);

		for (int32_t i = 0; i < drawCmdBuffers.size(); ++i)
		{
			renderPassBeginInfo.framebuffer = frameBuffers[i];
			VK_CHECK_RESULT(vkBeginCommandBuffer(drawCmdBuffers[i], &cmdBufInfo));
			vkCmdBeginRenderPass(drawCmdBuffers[i], &renderPassBeginInfo, VK_SUBPASS_CONTENTS_INLINE);
			vkCmdSetViewport(drawCmdBuffers[i], 0, 1, &viewport);
			vkCmdSetScissor(drawCmdBuffers[i], 0, 1, &scissor);
			// Bind scene matrices descriptor to set 0
			vkCmdBindDescriptorSets(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayout, 0, 1, &descriptorSet, 0, nullptr);
			vkCmdBindPipeline(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, wireframe ? pipelines.wireframe : pipelines.solid);
			glTFModel.draw(drawCmdBuffers[i], pipelineLayout);
			drawUI(drawCmdBuffers[i]);
			vkCmdEndRenderPass(drawCmdBuffers[i]);
			VK_CHECK_RESULT(vkEndCommandBuffer(drawCmdBuffers[i]));
		}
	}

	void VulkanExample::loadglTFFile(std::string filename)
	{
		tinygltf::Model glTFInput;
		tinygltf::TinyGLTF gltfContext;
		std::string error, warning;

		this->device = device;

#if defined(__ANDROID__)
		// On Android all assets are packed with the apk in a compressed form, so we need to open them using the asset manager
		// We let tinygltf handle this, by passing the asset manager of our app
		tinygltf::asset_manager = androidApp->activity->assetManager;
#endif
		bool fileLoaded = gltfContext.LoadASCIIFromFile(&glTFInput, &error, &warning, filename);

		// Pass some Vulkan resources required for setup and rendering to the glTF model loading class
		glTFModel.vulkanDevice = vulkanDevice;
		glTFModel.copyQueue = queue;

		std::vector<uint32_t> indexBuffer;
		std::vector<VulkanglTFModel::Vertex> vertexBuffer;

		if (fileLoaded) 
		{
			glTFModel.nodeCount = static_cast<uint32_t>(glTFInput.nodes.size());
			glTFModel.loadImages(glTFInput);
			glTFModel.loadMaterials(glTFInput);
			glTFModel.loadTextures(glTFInput);
			glTFModel.loadSkins(glTFInput);
			const tinygltf::Scene& scene = glTFInput.scenes[0];
			for (size_t i = 0; i < scene.nodes.size(); i++) {
				const tinygltf::Node node = glTFInput.nodes[scene.nodes[i]];
				glTFModel.loadNode(node, glTFInput, nullptr,scene.nodes[i], indexBuffer, vertexBuffer);
			}
			
			glTFModel.loadAnimations(glTFInput);
			// update joint in nodes
			
			for (auto node : glTFModel.nodes)
			{
				glTFModel.updateJoints(node);
			}
		}
		else {
			vks::tools::exitFatal("Could not open the glTF file.\n\nThe file is part of the additional asset pack.\n\nRun \"download_assets.py\" in the repository root to download the latest version.", -1);
			return;
		}

		// Create and upload vertex and index buffer
		// We will be using one single vertex buffer and one single index buffer for the whole glTF scene
		// Primitives (of the glTF model) will then index into these using index offsets

		size_t vertexBufferSize = vertexBuffer.size() * sizeof(VulkanglTFModel::Vertex);
		size_t indexBufferSize = indexBuffer.size() * sizeof(uint32_t);
		glTFModel.indices.count = static_cast<uint32_t>(indexBuffer.size());

		struct StagingBuffer {
			VkBuffer buffer;
			VkDeviceMemory memory;
		} vertexStaging, indexStaging;

		// Create host visible staging buffers (source)
		VK_CHECK_RESULT(vulkanDevice->createBuffer(
			VK_BUFFER_USAGE_TRANSFER_SRC_BIT,
			VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT,
			vertexBufferSize,
			&vertexStaging.buffer,
			&vertexStaging.memory,
			vertexBuffer.data()));
		// Index data
		VK_CHECK_RESULT(vulkanDevice->createBuffer(
			VK_BUFFER_USAGE_TRANSFER_SRC_BIT,
			VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT,
			indexBufferSize,
			&indexStaging.buffer,
			&indexStaging.memory,
			indexBuffer.data()));

		// Create device local buffers (target)
		VK_CHECK_RESULT(vulkanDevice->createBuffer(
			VK_BUFFER_USAGE_VERTEX_BUFFER_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT,
			VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT,
			vertexBufferSize,
			&glTFModel.vertices.buffer,
			&glTFModel.vertices.memory));
		VK_CHECK_RESULT(vulkanDevice->createBuffer(
			VK_BUFFER_USAGE_INDEX_BUFFER_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT,
			VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT,
			indexBufferSize,
			&glTFModel.indices.buffer,
			&glTFModel.indices.memory));

		// Copy data from staging buffers (host) do device local buffer (gpu)
		VkCommandBuffer copyCmd = vulkanDevice->createCommandBuffer(VK_COMMAND_BUFFER_LEVEL_PRIMARY, true);
		VkBufferCopy copyRegion = {};

		copyRegion.size = vertexBufferSize;
		vkCmdCopyBuffer(
			copyCmd,
			vertexStaging.buffer,
			glTFModel.vertices.buffer,
			1,
			&copyRegion);

		copyRegion.size = indexBufferSize;

		vkCmdCopyBuffer(
			copyCmd,
			indexStaging.buffer,
			glTFModel.indices.buffer,
			1,
			&copyRegion);

		vulkanDevice->flushCommandBuffer(copyCmd, queue, true);

		// Free staging resources
		vkDestroyBuffer(device, vertexStaging.buffer, nullptr);
		vkFreeMemory(device, vertexStaging.memory, nullptr);
		vkDestroyBuffer(device, indexStaging.buffer, nullptr);
		vkFreeMemory(device, indexStaging.memory, nullptr);
	}

	void VulkanExample::loadAssets()
	{
		loadglTFFile(getAssetPath() + "buster_drone/busterDrone.gltf");
	}

	void VulkanExample::setupDescriptors()
	{
		/*
			This sample uses separate descriptor sets (and layouts) for the matrices and materials (textures)
		*/

		std::vector<VkDescriptorPoolSize> poolSizes = {
		vks::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, 1),
		// One combined image sampler per material image/texture
		vks::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, static_cast<uint32_t>(glTFModel.images.size())),
		// One ssbo per skin
		vks::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_STORAGE_BUFFER, static_cast<uint32_t>(glTFModel.skins.size())),
		};
		// Number of descriptor sets = One for the scene ubo + one per image + one per skin
		const uint32_t             maxSetCount = static_cast<uint32_t>(glTFModel.images.size()) + static_cast<uint32_t>(glTFModel.skins.size()) + 1;
		VkDescriptorPoolCreateInfo descriptorPoolInfo = vks::initializers::descriptorPoolCreateInfo(poolSizes, maxSetCount);
		VK_CHECK_RESULT(vkCreateDescriptorPool(device, &descriptorPoolInfo, nullptr, &descriptorPool));

		// Descriptor set layouts
		VkDescriptorSetLayoutBinding    setLayoutBinding{};
		VkDescriptorSetLayoutCreateInfo descriptorSetLayoutCI = vks::initializers::descriptorSetLayoutCreateInfo(&setLayoutBinding, 1);

		// Descriptor set layout for passing matrices
		setLayoutBinding = vks::initializers::descriptorSetLayoutBinding(VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, VK_SHADER_STAGE_VERTEX_BIT, 0);
		VK_CHECK_RESULT(vkCreateDescriptorSetLayout(device, &descriptorSetLayoutCI, nullptr, &descriptorSetLayouts.matrices));

		// Descriptor set layout for passing material textures
		setLayoutBinding = vks::initializers::descriptorSetLayoutBinding(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, VK_SHADER_STAGE_FRAGMENT_BIT, 0);
		VK_CHECK_RESULT(vkCreateDescriptorSetLayout(device, &descriptorSetLayoutCI, nullptr, &descriptorSetLayouts.textures));

		// Descriptor set layout for passing skin joint matrices
		setLayoutBinding = vks::initializers::descriptorSetLayoutBinding(VK_DESCRIPTOR_TYPE_STORAGE_BUFFER, VK_SHADER_STAGE_VERTEX_BIT, 0);
		VK_CHECK_RESULT(vkCreateDescriptorSetLayout(device, &descriptorSetLayoutCI, nullptr, &descriptorSetLayouts.jointMatrices));

		// The pipeline layout uses three sets:
		// Set 0 = Scene matrices (VS)
		// Set 1 = Joint matrices (VS)
		// Set 2 = Material texture (FS)
		std::array<VkDescriptorSetLayout, 3> setLayouts = {
			descriptorSetLayouts.matrices,
			descriptorSetLayouts.jointMatrices,
			descriptorSetLayouts.textures };
		VkPipelineLayoutCreateInfo pipelineLayoutCI = vks::initializers::pipelineLayoutCreateInfo(setLayouts.data(), static_cast<uint32_t>(setLayouts.size()));

		// We will use push constants to push the local matrices of a primitive to the vertex shader
		VkPushConstantRange pushConstantRange = vks::initializers::pushConstantRange(VK_SHADER_STAGE_VERTEX_BIT, sizeof(glm::mat4), 0);
		// Push constant ranges are part of the pipeline layout
		pipelineLayoutCI.pushConstantRangeCount = 1;
		pipelineLayoutCI.pPushConstantRanges = &pushConstantRange;
		VK_CHECK_RESULT(vkCreatePipelineLayout(device, &pipelineLayoutCI, nullptr, &pipelineLayout));

		// Descriptor set for scene matrices
		VkDescriptorSetAllocateInfo allocInfo = vks::initializers::descriptorSetAllocateInfo(descriptorPool, &descriptorSetLayouts.matrices, 1);
		VK_CHECK_RESULT(vkAllocateDescriptorSets(device, &allocInfo, &descriptorSet));
		VkWriteDescriptorSet writeDescriptorSet = vks::initializers::writeDescriptorSet(descriptorSet, VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, 0, &shaderData.buffer.descriptor);
		vkUpdateDescriptorSets(device, 1, &writeDescriptorSet, 0, nullptr);

		// Descriptor set for glTF model skin joint matrices
		for (auto& skin : glTFModel.skins)
		{
			const VkDescriptorSetAllocateInfo allocInfo = vks::initializers::descriptorSetAllocateInfo(descriptorPool, &descriptorSetLayouts.jointMatrices, 1);
			VK_CHECK_RESULT(vkAllocateDescriptorSets(device, &allocInfo, &skin.descriptorSet));
			VkWriteDescriptorSet writeDescriptorSet = vks::initializers::writeDescriptorSet(skin.descriptorSet, VK_DESCRIPTOR_TYPE_STORAGE_BUFFER, 0, &skin.ssbo.descriptor);
			vkUpdateDescriptorSets(device, 1, &writeDescriptorSet, 0, nullptr);
		}

		// Descriptor sets for glTF model materials
		for (auto& image : glTFModel.images)
		{
			const VkDescriptorSetAllocateInfo allocInfo = vks::initializers::descriptorSetAllocateInfo(descriptorPool, &descriptorSetLayouts.textures, 1);
			VK_CHECK_RESULT(vkAllocateDescriptorSets(device, &allocInfo, &image.descriptorSet));
			VkWriteDescriptorSet writeDescriptorSet = vks::initializers::writeDescriptorSet(image.descriptorSet, VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 0, &image.texture.descriptor);
			vkUpdateDescriptorSets(device, 1, &writeDescriptorSet, 0, nullptr);
		}
		
	}

	void VulkanExample::preparePipelines()
	{
		VkPipelineInputAssemblyStateCreateInfo inputAssemblyStateCI = vks::initializers::pipelineInputAssemblyStateCreateInfo(VK_PRIMITIVE_TOPOLOGY_TRIANGLE_LIST, 0, VK_FALSE);
		VkPipelineRasterizationStateCreateInfo rasterizationStateCI = vks::initializers::pipelineRasterizationStateCreateInfo(VK_POLYGON_MODE_FILL, VK_CULL_MODE_BACK_BIT, VK_FRONT_FACE_COUNTER_CLOCKWISE, 0);
		VkPipelineColorBlendAttachmentState blendAttachmentStateCI = vks::initializers::pipelineColorBlendAttachmentState(0xf, VK_FALSE);
		VkPipelineColorBlendStateCreateInfo colorBlendStateCI = vks::initializers::pipelineColorBlendStateCreateInfo(1, &blendAttachmentStateCI);
		VkPipelineDepthStencilStateCreateInfo depthStencilStateCI = vks::initializers::pipelineDepthStencilStateCreateInfo(VK_TRUE, VK_TRUE, VK_COMPARE_OP_LESS_OR_EQUAL);
		VkPipelineViewportStateCreateInfo viewportStateCI = vks::initializers::pipelineViewportStateCreateInfo(1, 1, 0);
		VkPipelineMultisampleStateCreateInfo multisampleStateCI = vks::initializers::pipelineMultisampleStateCreateInfo(VK_SAMPLE_COUNT_1_BIT, 0);
		const std::vector<VkDynamicState> dynamicStateEnables = { VK_DYNAMIC_STATE_VIEWPORT, VK_DYNAMIC_STATE_SCISSOR };
		VkPipelineDynamicStateCreateInfo dynamicStateCI = vks::initializers::pipelineDynamicStateCreateInfo(dynamicStateEnables.data(), static_cast<uint32_t>(dynamicStateEnables.size()), 0);
		// Vertex input bindings and attributes
		const std::vector<VkVertexInputBindingDescription> vertexInputBindings = {
			vks::initializers::vertexInputBindingDescription(0, sizeof(VulkanglTFModel::Vertex), VK_VERTEX_INPUT_RATE_VERTEX),
		};
		const std::vector<VkVertexInputAttributeDescription> vertexInputAttributes = {
		{0, 0, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, pos)},
		{1, 0, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, normal)},
		{2, 0, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, uv)},
		{3, 0, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, color)},
		// POI: Per-Vertex Joint indices and weights are passed to the vertex shader
		{4, 0, VK_FORMAT_R32G32B32A32_SFLOAT, offsetof(VulkanglTFModel::Vertex, jointIndices)},
		{5, 0, VK_FORMAT_R32G32B32A32_SFLOAT, offsetof(VulkanglTFModel::Vertex, jointWeights)},
		};
		VkPipelineVertexInputStateCreateInfo vertexInputStateCI = vks::initializers::pipelineVertexInputStateCreateInfo();
		vertexInputStateCI.vertexBindingDescriptionCount = static_cast<uint32_t>(vertexInputBindings.size());
		vertexInputStateCI.pVertexBindingDescriptions = vertexInputBindings.data();
		vertexInputStateCI.vertexAttributeDescriptionCount = static_cast<uint32_t>(vertexInputAttributes.size());
		vertexInputStateCI.pVertexAttributeDescriptions = vertexInputAttributes.data();

		const std::array<VkPipelineShaderStageCreateInfo, 2> shaderStages = {
			loadShader(getHomeworkShadersPath() + "homework1/mesh.vert.spv", VK_SHADER_STAGE_VERTEX_BIT),
			loadShader(getHomeworkShadersPath() + "homework1/mesh.frag.spv", VK_SHADER_STAGE_FRAGMENT_BIT)
		};

		VkGraphicsPipelineCreateInfo pipelineCI = vks::initializers::pipelineCreateInfo(pipelineLayout, renderPass, 0);
		pipelineCI.pVertexInputState = &vertexInputStateCI;
		pipelineCI.pInputAssemblyState = &inputAssemblyStateCI;
		pipelineCI.pRasterizationState = &rasterizationStateCI;
		pipelineCI.pColorBlendState = &colorBlendStateCI;
		pipelineCI.pMultisampleState = &multisampleStateCI;
		pipelineCI.pViewportState = &viewportStateCI;
		pipelineCI.pDepthStencilState = &depthStencilStateCI;
		pipelineCI.pDynamicState = &dynamicStateCI;
		pipelineCI.stageCount = static_cast<uint32_t>(shaderStages.size());
		pipelineCI.pStages = shaderStages.data();

		// Solid rendering pipeline
		VK_CHECK_RESULT(vkCreateGraphicsPipelines(device, pipelineCache, 1, &pipelineCI, nullptr, &pipelines.solid));

		// Wire frame rendering pipeline
		if (deviceFeatures.fillModeNonSolid) {
			rasterizationStateCI.polygonMode = VK_POLYGON_MODE_LINE;
			rasterizationStateCI.lineWidth = 1.0f;
			VK_CHECK_RESULT(vkCreateGraphicsPipelines(device, pipelineCache, 1, &pipelineCI, nullptr, &pipelines.wireframe));
		}
	}

	// Prepare and initialize uniform buffer containing shader uniforms
	void VulkanExample::prepareUniformBuffers()
	{
		// Vertex shader uniform buffer block
		VK_CHECK_RESULT(vulkanDevice->createBuffer(
			VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT,
			VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT,
			&shaderData.buffer,
			sizeof(shaderData.values)));

		// Map persistent
		VK_CHECK_RESULT(shaderData.buffer.map());

		updateUniformBuffers();
	}

	void VulkanExample::updateUniformBuffers()
	{
		shaderData.values.projection = camera.matrices.perspective;
		shaderData.values.model = camera.matrices.view;
		
		memcpy(shaderData.buffer.mapped, &shaderData.values, sizeof(shaderData.values));
	}

	void VulkanExample::prepare()
	{
		VulkanExampleBase::prepare();
		loadAssets();
		prepareUniformBuffers();
		setupDescriptors();
		preparePipelines();
		buildCommandBuffers();
		prepared = true;
	}

	void VulkanExample::render()
	{
		renderFrame();
		if (camera.updated) {
			updateUniformBuffers();
		}
		if (!paused)
		{
			glTFModel.updateAnimation(frameTimer,shaderData.skinSSBO);
		}
	}

	void VulkanExample::viewChanged()
	{
		updateUniformBuffers();
	}

	void VulkanExample::OnUpdateUIOverlay(vks::UIOverlay *overlay)
	{
		if (overlay->header("Settings")) {
			if (overlay->checkBox("Wireframe", &wireframe)) {
				buildCommandBuffers();
			}
		}
		if (overlay->header("Animation"))
		{
			overlay->checkBox("pause", &paused);
		}
	}


VULKAN_EXAMPLE_MAIN()