plumageRender/src/render/render.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/
 */

#ifndef TINYGLTF_IMPLEMENTATION
#define TINYGLTF_IMPLEMENTATION
#endif
#ifndef STB_IMAGE_IMPLEMENTATION
#define STB_IMAGE_IMPLEMENTATION
#endif

#ifndef TINYGLTF_NO_STB_IMAGE_WRITE
#define TINYGLTF_NO_STB_IMAGE_WRITE
#endif


#include "render.h"
#include "GUIFunction.h"



	VulkanExample::VulkanExample():
		VulkanExampleBase(ENABLE_VALIDATION)
	{
		title = "render";
		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::setupFrameBuffer()
	{
		VulkanExampleBase::setupFrameBuffer();
		if (pbrFrameBuffer.bCreate && (pbrFrameBuffer.fbo.width != width || pbrFrameBuffer.fbo.height != height))
		{
			pbrFrameBuffer.color.destroy(device);
			pbrFrameBuffer.depth.destroy(device);
			pbrFrameBuffer.fbo.destroy(device);
			vkDestroySampler(device, colorSampler, nullptr);
		}

		//Create image color attachment
		pbrFrameBuffer.fbo.setSize(width, height);
		VkFormat attDepthFormat;
		VkBool32 validDepthFormat = vks::tools::getSupportedDepthFormat(physicalDevice, &attDepthFormat);
		assert(validDepthFormat);

		createAttachment(VK_FORMAT_R8G8B8A8_UNORM, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT, &pbrFrameBuffer.color, width, height);
		createAttachment(attDepthFormat, VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT, &pbrFrameBuffer.depth, width, height);
		{
			std::array<VkAttachmentDescription, 2> attachs = {};
			for (uint32_t i = 0; i < static_cast<uint32_t>(attachs.size()); ++i)
			{
				attachs[i].samples = VK_SAMPLE_COUNT_1_BIT;
				attachs[i].loadOp = VK_ATTACHMENT_LOAD_OP_CLEAR;
				attachs[i].storeOp = VK_ATTACHMENT_STORE_OP_STORE;
				attachs[i].stencilLoadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE;
				attachs[i].stencilStoreOp = VK_ATTACHMENT_STORE_OP_DONT_CARE;
				attachs[i].initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;
				attachs[i].finalLayout = i == 1 ? VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL : VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
			}
			attachs[0].format = pbrFrameBuffer.color.format;
			attachs[1].format = pbrFrameBuffer.depth.format;

			VkAttachmentReference colorReference = {};
			colorReference.attachment = 0;
			colorReference.layout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;

			VkAttachmentReference depthReference = {};
			depthReference.attachment = 1;
			depthReference.layout = VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL;

			VkSubpassDescription subpass = {};
			subpass.pipelineBindPoint = VK_PIPELINE_BIND_POINT_GRAPHICS;
			subpass.pColorAttachments = &colorReference;
			subpass.colorAttachmentCount = 1;
			subpass.pDepthStencilAttachment = &depthReference;

			std::array<VkSubpassDependency, 2> dependencies;
			//To test src 0
			dependencies[0].srcSubpass = VK_SUBPASS_EXTERNAL;
			dependencies[0].dstSubpass = 0;
			dependencies[0].srcStageMask = VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT;
			dependencies[0].dstStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
			dependencies[0].srcAccessMask = VK_ACCESS_SHADER_READ_BIT;
			dependencies[0].dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
			dependencies[0].dependencyFlags = VK_DEPENDENCY_BY_REGION_BIT;

			dependencies[1].srcSubpass = 0;
			dependencies[1].dstSubpass = VK_SUBPASS_EXTERNAL;
			dependencies[1].srcStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
			dependencies[1].dstStageMask = VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT;
			dependencies[1].srcAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
			dependencies[1].dstAccessMask = VK_ACCESS_SHADER_READ_BIT;
			dependencies[1].dependencyFlags = VK_DEPENDENCY_BY_REGION_BIT;

			VkRenderPassCreateInfo renderPassCI = {};
			renderPassCI.sType = VK_STRUCTURE_TYPE_RENDER_PASS_CREATE_INFO;
			renderPassCI.pAttachments = attachs.data();
			renderPassCI.attachmentCount = static_cast<uint32_t>(attachs.size());
			renderPassCI.pSubpasses = &subpass;
			renderPassCI.subpassCount = 1;
			renderPassCI.pDependencies = dependencies.data();
			renderPassCI.dependencyCount = 2;
			VK_CHECK_RESULT(vkCreateRenderPass(device, &renderPassCI, nullptr, &pbrFrameBuffer.fbo.renderPass));

			//Create FBO
			VkImageView attachments[2] = { pbrFrameBuffer.color.imageView, pbrFrameBuffer.depth.imageView };
			VkFramebufferCreateInfo fbufCreateInfo = vks::initializers::framebufferCreateInfo();
			fbufCreateInfo.renderPass = pbrFrameBuffer.fbo.renderPass;
			fbufCreateInfo.pAttachments = attachments;
			fbufCreateInfo.attachmentCount = 2;
			fbufCreateInfo.width = pbrFrameBuffer.fbo.width;
			fbufCreateInfo.height = pbrFrameBuffer.fbo.height;
			fbufCreateInfo.layers = 1;
			VK_CHECK_RESULT(vkCreateFramebuffer(device, &fbufCreateInfo, nullptr, &pbrFrameBuffer.fbo.frameBuffer));
		}

		//Create Image sampler
		VkSamplerCreateInfo samplerCI = vks::initializers::samplerCreateInfo();
		samplerCI.magFilter = VK_FILTER_NEAREST;
		samplerCI.minFilter = VK_FILTER_NEAREST;
		samplerCI.mipmapMode = VK_SAMPLER_MIPMAP_MODE_LINEAR;
		samplerCI.addressModeU = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
		samplerCI.addressModeV = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
		samplerCI.addressModeW = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
		//samplerCI.mipLodBias = 0.0f;
		//samplerCI.maxAnisotropy = 1.0f;
		samplerCI.minLod = 0.0f;
		samplerCI.maxLod = 1.0f;
		samplerCI.borderColor = VK_BORDER_COLOR_FLOAT_OPAQUE_WHITE;
		VK_CHECK_RESULT(vkCreateSampler(device, &samplerCI, nullptr, &colorSampler));

		if (tonemappingDescriptorSet != VK_NULL_HANDLE) //Bad logic 
		{
			auto imageInfo = vks::initializers::descriptorImageInfo(colorSampler, pbrFrameBuffer.color.imageView, VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL);
			VkWriteDescriptorSet writeDescriptorSet = vks::initializers::writeDescriptorSet(tonemappingDescriptorSet, VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 0, &imageInfo);
			vkUpdateDescriptorSets(device, 1, &writeDescriptorSet, 0, nullptr);
		}
		pbrFrameBuffer.bCreate = 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 = pbrFrameBuffer.fbo.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 = pbrFrameBuffer.fbo.frameBuffer;
			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, pipelineLayouts.pbrLayout, 0, 1, &descriptorSet, 0, nullptr);
			vkCmdBindDescriptorSets(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayouts.pbrLayout, 6, 1, &skinDescriptorSet, 0, nullptr);
			vkCmdBindPipeline(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, wireframe ? pipelines.wireframe : pipelines.solid);
			glTFModel.draw(drawCmdBuffers[i], pipelineLayouts.pbrLayout,false);
			vkCmdEndRenderPass(drawCmdBuffers[i]);

			{
				VkRenderPassBeginInfo renderPassBeginInfo = vks::initializers::renderPassBeginInfo();
				renderPassBeginInfo.renderPass = renderPass;
				renderPassBeginInfo.framebuffer = VulkanExampleBase::frameBuffers[i];
				renderPassBeginInfo.renderArea.extent.width = width;
				renderPassBeginInfo.renderArea.extent.height = height;
				renderPassBeginInfo.clearValueCount = 2;
				renderPassBeginInfo.pClearValues = clearValues;

				vkCmdBeginRenderPass(drawCmdBuffers[i], &renderPassBeginInfo, VK_SUBPASS_CONTENTS_INLINE);
				vkCmdSetViewport(drawCmdBuffers[i], 0, 1, &viewport);
				vkCmdSetScissor(drawCmdBuffers[i], 0, 1, &scissor);
				vkCmdBindDescriptorSets(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayouts.tonemappingLayout, 0, 1, &tonemappingDescriptorSet, 0, NULL);
				vkCmdBindPipeline(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, pipelines.toneMapping);
				vkCmdDraw(drawCmdBuffers[i], 3, 1, 0, 0);
				drawUI(drawCmdBuffers[i]);
				vkCmdEndRenderPass(drawCmdBuffers[i]);
			}
			VK_CHECK_RESULT(vkEndCommandBuffer(drawCmdBuffers[i]));
		}
	}

	void VulkanExample::loadglTFFile(std::string filename, VulkanglTFModel& model, bool bSkyboxFlag = false)
	{
		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
		model.vulkanDevice = vulkanDevice;
		model.copyQueue = queue;

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

		if (fileLoaded) {
			model.nodeCount = static_cast<uint32_t>(glTFInput.nodes.size());
			model.loadImages(glTFInput);
			model.loadMaterials(glTFInput);
			model.loadTextures(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]];
				model.loadNode(node, glTFInput, nullptr, scene.nodes[i], indexBuffer, vertexBuffer);
			}
			model.loadAnimations(glTFInput);
		}
		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);
		model.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,
			&model.vertices.buffer,
			&model.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,
			&model.indices.buffer,
			&model.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,
			model.vertices.buffer,
			1,
			&copyRegion);

		copyRegion.size = indexBufferSize;
		vkCmdCopyBuffer(
			copyCmd,
			indexStaging.buffer,
			model.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", glTFModel);
		loadglTFFile(getAssetPath() + "models/cube.gltf", skyboxModel, true);
		ibltextures.skyboxCube.loadFromFile(getAssetPath() + "textures/hdr/pisa_cube.ktx", VK_FORMAT_R16G16B16A16_SFLOAT, vulkanDevice, queue);
	}

	void VulkanExample::setupDescriptors()
	{
		/*
			This sample uses separate descriptor sets (and layouts) for the matrices and materials (textures)
		*/
		//Descriptor Pool Alloc
		{
			std::vector<VkDescriptorPoolSize> poolSizes = {
				vks::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, 4),
				// One combined image sampler per model image/texture
				vks::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, static_cast<uint32_t>(glTFModel.images.size())),
				vks::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 4), // Add aditional sampler descriptor
				vks::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_STORAGE_BUFFER, 1)
			};
			// One set for matrices and one per model image/texture
			const uint32_t maxSetCount = static_cast<uint32_t>(glTFModel.images.size()) + 6;
			VkDescriptorPoolCreateInfo descriptorPoolInfo = vks::initializers::descriptorPoolCreateInfo(poolSizes, maxSetCount);
			VK_CHECK_RESULT(vkCreateDescriptorPool(device, &descriptorPoolInfo, nullptr, &descriptorPool));
		}


		// Descriptor set layout for passing matrices ---and precompute texture add in this descriptor
		std::vector<VkDescriptorSetLayoutBinding> setLayoutBindings = 
		{
			vks::initializers::descriptorSetLayoutBinding(VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT, 0),
			vks::initializers::descriptorSetLayoutBinding(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, VK_SHADER_STAGE_FRAGMENT_BIT, 1),
			vks::initializers::descriptorSetLayoutBinding(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, VK_SHADER_STAGE_FRAGMENT_BIT, 2),
			vks::initializers::descriptorSetLayoutBinding(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, VK_SHADER_STAGE_FRAGMENT_BIT, 3),
		};
		VkDescriptorSetLayoutCreateInfo descriptorSetLayoutCI = vks::initializers::descriptorSetLayoutCreateInfo(setLayoutBindings);
		VK_CHECK_RESULT(vkCreateDescriptorSetLayout(device, &descriptorSetLayoutCI, nullptr, &descriptorSetLayouts.matrices));

		VkDescriptorSetLayoutBinding materialBufferLayoutBinding = vks::initializers::descriptorSetLayoutBinding(VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, VK_SHADER_STAGE_FRAGMENT_BIT, 0);
		descriptorSetLayoutCI = vks::initializers::descriptorSetLayoutCreateInfo(&materialBufferLayoutBinding, 1);
		VK_CHECK_RESULT(vkCreateDescriptorSetLayout(device, &descriptorSetLayoutCI, nullptr, &descriptorSetLayouts.materialUniform));

		// Descriptor set layout for passing material textures
		VkDescriptorSetLayoutBinding setLayoutBinding = vks::initializers::descriptorSetLayoutBinding(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, VK_SHADER_STAGE_FRAGMENT_BIT, 0);
		descriptorSetLayoutCI = vks::initializers::descriptorSetLayoutCreateInfo(&setLayoutBinding, 1);
		VK_CHECK_RESULT(vkCreateDescriptorSetLayout(device, &descriptorSetLayoutCI, nullptr, &descriptorSetLayouts.textures));

		setLayoutBinding = vks::initializers::descriptorSetLayoutBinding(VK_DESCRIPTOR_TYPE_STORAGE_BUFFER, VK_SHADER_STAGE_VERTEX_BIT, 0);
		VK_CHECK_RESULT(vkCreateDescriptorSetLayout(device, &descriptorSetLayoutCI, nullptr, &descriptorSetLayouts.ssbo));
		//Pbr pipeline layout
		{
			// Pipeline layout using both descriptor sets (set 0 = matrices, set 1 = material) 
			std::array<VkDescriptorSetLayout, 7> setLayouts =
			{ descriptorSetLayouts.matrices,
				descriptorSetLayouts.textures,
				descriptorSetLayouts.textures,
				descriptorSetLayouts.textures,
				descriptorSetLayouts.textures,
				descriptorSetLayouts.materialUniform,
				descriptorSetLayouts.ssbo
			};
			VkPipelineLayoutCreateInfo pipelineLayoutCI = vks::initializers::pipelineLayoutCreateInfo(setLayouts.data(), static_cast<uint32_t>(setLayouts.size()));
			VK_CHECK_RESULT(vkCreatePipelineLayout(device, &pipelineLayoutCI, nullptr, &pipelineLayouts.pbrLayout));

			// Descriptor set for scene matrices
			VkDescriptorSetAllocateInfo allocInfo = vks::initializers::descriptorSetAllocateInfo(descriptorPool, &descriptorSetLayouts.matrices, 1);
			VK_CHECK_RESULT(vkAllocateDescriptorSets(device, &allocInfo, &descriptorSet));
			std::vector<VkWriteDescriptorSet> writeDescriptorSets =
			{
				vks::initializers::writeDescriptorSet(descriptorSet, VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, 0, &shaderData.buffer.descriptor),
				vks::initializers::writeDescriptorSet(descriptorSet, VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 1, &ibltextures.irradianceCube.descriptor),
				vks::initializers::writeDescriptorSet(descriptorSet, VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 2, &ibltextures.lutBrdf.descriptor),
				vks::initializers::writeDescriptorSet(descriptorSet, VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 3, &ibltextures.prefilteredCube.descriptor),
			};
			vkUpdateDescriptorSets(device, 4, writeDescriptorSets.data(), 0, nullptr);

			for (auto& material : glTFModel.materials)
			{
				const VkDescriptorSetAllocateInfo allocInfo = vks::initializers::descriptorSetAllocateInfo(descriptorPool, &descriptorSetLayouts.materialUniform, 1);
				VK_CHECK_RESULT(vkAllocateDescriptorSets(device, &allocInfo, &material.materialData.descriptorSet));
				VkWriteDescriptorSet writeDescriptorSet = vks::initializers::writeDescriptorSet(
					material.materialData.descriptorSet, VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, 0, &material.materialData.buffer.descriptor);
				vkUpdateDescriptorSets(device, 1, &writeDescriptorSet, 0, nullptr);
			}

			// Descriptor sets for 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);
			}
			{
				const VkDescriptorSetAllocateInfo allocInfo = vks::initializers::descriptorSetAllocateInfo(descriptorPool, &descriptorSetLayouts.ssbo, 1);
				VK_CHECK_RESULT(vkAllocateDescriptorSets(device, &allocInfo, &skinDescriptorSet));
				VkWriteDescriptorSet writeDescriptorSet = vks::initializers::writeDescriptorSet(skinDescriptorSet, VK_DESCRIPTOR_TYPE_STORAGE_BUFFER, 0, &shaderData.skinSSBO.descriptor);
				vkUpdateDescriptorSets(device, 1, &writeDescriptorSet, 0, nullptr);
			}
		}
		//Tone Mapping pipeline layout
		{
			auto pipelineLayoutCI = vks::initializers::pipelineLayoutCreateInfo(&descriptorSetLayouts.textures, 1);
			VK_CHECK_RESULT(vkCreatePipelineLayout(device, &pipelineLayoutCI, nullptr, &pipelineLayouts.tonemappingLayout));

			const VkDescriptorSetAllocateInfo allocInfo = vks::initializers::descriptorSetAllocateInfo(descriptorPool, &descriptorSetLayouts.textures, 1);
			VK_CHECK_RESULT(vkAllocateDescriptorSets(device, &allocInfo, &tonemappingDescriptorSet));

			auto imageInfo = vks::initializers::descriptorImageInfo(colorSampler, pbrFrameBuffer.color.imageView, VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL);
			VkWriteDescriptorSet writeDescriptorSet = vks::initializers::writeDescriptorSet(tonemappingDescriptorSet, VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 0, &imageInfo);
			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 = {
			vks::initializers::vertexInputAttributeDescription(0, 0, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, pos)),	// Location 0: Position
			vks::initializers::vertexInputAttributeDescription(0, 1, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, normal)),// Location 1: Normal
			vks::initializers::vertexInputAttributeDescription(0, 2, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, uv)),	// Location 2: Texture coordinates
			vks::initializers::vertexInputAttributeDescription(0, 3, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, color)),	// Location 3: Color
			vks::initializers::vertexInputAttributeDescription(0, 4, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, tangent)), // Location 4 : Tangent
		};
		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();

		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(pipelineLayouts.pbrLayout, pbrFrameBuffer.fbo.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));
		}
		//Create Tone Mapping render pipeline
		CreateToneMappingPipeline();
	}

	void VulkanExample::CreateToneMappingPipeline()
	{
		if (pipelines.toneMapping != VK_NULL_HANDLE)
		{
			vkDestroyPipeline(device, pipelines.toneMapping, nullptr);
			pipelines.toneMapping = VK_NULL_HANDLE;
		}
		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_NONE, 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_FALSE, VK_FALSE, 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);
		VkPipelineVertexInputStateCreateInfo emptyInputState = vks::initializers::pipelineVertexInputStateCreateInfo();


		const std::string fragPath = ToneMapping ? "homework1/tonemapping_enable.frag.spv" : "homework1/tonemapping_disable.frag.spv";
		std::array<VkPipelineShaderStageCreateInfo, 2> shaderStages = {
			loadShader(getHomeworkShadersPath() + "homework1/genbrdflut.vert.spv", VK_SHADER_STAGE_VERTEX_BIT),
			loadShader(getHomeworkShadersPath() + fragPath, VK_SHADER_STAGE_FRAGMENT_BIT)
		};

		VkGraphicsPipelineCreateInfo pipelineCI = vks::initializers::pipelineCreateInfo(pipelineLayouts.tonemappingLayout, renderPass, 0);
		pipelineCI.pVertexInputState = &emptyInputState;
		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();

		VK_CHECK_RESULT(vkCreateGraphicsPipelines(device, pipelineCache, 1, &pipelineCI, nullptr, &pipelines.toneMapping));
	}


	//----------------------------Prepare precompute Lighting or BRDF LUT-----------------------------------------------//
	//Irradiance map for diffuse lighting
	void VulkanExample::GenerateIrradianceCubemap()
	{
		auto tStart = std::chrono::high_resolution_clock::now();

		constexpr VkFormat format = VK_FORMAT_R32G32B32A32_SFLOAT;
		constexpr int32_t dim = 64;
		const uint32_t numMips = static_cast<uint32_t>(floor(log2(dim))) + 1;

		VkImageCreateInfo imageCI = vks::initializers::imageCreateInfo();
		imageCI.imageType = VK_IMAGE_TYPE_2D;
		imageCI.format = format;
		imageCI.extent.width = dim;
		imageCI.extent.height = dim;
		imageCI.extent.depth = 1;
		imageCI.mipLevels = numMips;
		imageCI.arrayLayers = 6;
		imageCI.samples = VK_SAMPLE_COUNT_1_BIT;
		imageCI.tiling = VK_IMAGE_TILING_OPTIMAL;
		imageCI.usage = VK_IMAGE_USAGE_SAMPLED_BIT | VK_IMAGE_USAGE_TRANSFER_DST_BIT;
		imageCI.flags = VK_IMAGE_CREATE_CUBE_COMPATIBLE_BIT;
		VK_CHECK_RESULT(vkCreateImage(device, &imageCI, nullptr, &ibltextures.irradianceCube.image))
		VkMemoryAllocateInfo memAlloc = vks::initializers::memoryAllocateInfo();
		VkMemoryRequirements memReqs;
		vkGetImageMemoryRequirements(device, ibltextures.irradianceCube.image, &memReqs);
		memAlloc.allocationSize = memReqs.size;
		memAlloc.memoryTypeIndex = vulkanDevice->getMemoryType(memReqs.memoryTypeBits, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT);
		VK_CHECK_RESULT(vkAllocateMemory(device, &memAlloc, nullptr, &ibltextures.irradianceCube.deviceMemory))
		VK_CHECK_RESULT(vkBindImageMemory(device, ibltextures.irradianceCube.image, ibltextures.irradianceCube.deviceMemory, 0))
		VkImageViewCreateInfo viewCI = vks::initializers::imageViewCreateInfo();
		viewCI.viewType = VK_IMAGE_VIEW_TYPE_CUBE;
		viewCI.format = format;
		viewCI.subresourceRange = {};
		viewCI.subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
		viewCI.subresourceRange.levelCount = numMips;
		viewCI.subresourceRange.layerCount = 6;
		viewCI.image = ibltextures.irradianceCube.image;
		VK_CHECK_RESULT(vkCreateImageView(device, &viewCI, nullptr, &ibltextures.irradianceCube.view))

		VkSamplerCreateInfo samplerCI = vks::initializers::samplerCreateInfo();
		samplerCI.magFilter = VK_FILTER_LINEAR;
		samplerCI.minFilter = VK_FILTER_LINEAR;
		samplerCI.mipmapMode = VK_SAMPLER_MIPMAP_MODE_LINEAR;
		samplerCI.addressModeU = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
		samplerCI.addressModeV = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
		samplerCI.addressModeW = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
		samplerCI.minLod = 0.0f;
		samplerCI.maxLod = static_cast<float>(numMips);
		samplerCI.borderColor = VK_BORDER_COLOR_FLOAT_OPAQUE_WHITE;
		VK_CHECK_RESULT(vkCreateSampler(device, &samplerCI, nullptr, &ibltextures.irradianceCube.sampler))

		ibltextures.irradianceCube.descriptor.imageView = ibltextures.irradianceCube.view;
		ibltextures.irradianceCube.descriptor.sampler = ibltextures.irradianceCube.sampler;
		ibltextures.irradianceCube.descriptor.imageLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
		ibltextures.irradianceCube.device = vulkanDevice;

		//Setup Framebuffer and so on
		VkAttachmentDescription attDesc = {};
		attDesc.format = format;
		attDesc.samples = VK_SAMPLE_COUNT_1_BIT;
		attDesc.loadOp = VK_ATTACHMENT_LOAD_OP_CLEAR;
		attDesc.storeOp = VK_ATTACHMENT_STORE_OP_STORE;
		attDesc.stencilLoadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE;
		attDesc.stencilStoreOp = VK_ATTACHMENT_STORE_OP_DONT_CARE;
		attDesc.initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;
		attDesc.finalLayout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
		
		VkAttachmentReference colorReference = { 0, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL };
		VkSubpassDescription subpassDescription = {};
		subpassDescription.pipelineBindPoint = VK_PIPELINE_BIND_POINT_GRAPHICS;
		subpassDescription.colorAttachmentCount = 1;
		subpassDescription.pColorAttachments = &colorReference;

		std::array<VkSubpassDependency, 2> dependencies;
		dependencies[0].srcSubpass = VK_SUBPASS_EXTERNAL;
		dependencies[0].dstSubpass = 0;
		dependencies[0].srcStageMask = VK_PIPELINE_STAGE_BOTTOM_OF_PIPE_BIT;
		dependencies[0].dstStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
		dependencies[0].srcAccessMask = VK_ACCESS_MEMORY_READ_BIT;
		dependencies[0].dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_READ_BIT | VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
		dependencies[0].dependencyFlags = VK_DEPENDENCY_BY_REGION_BIT;
		dependencies[1].srcSubpass = 0;
		dependencies[1].dstSubpass = VK_SUBPASS_EXTERNAL;
		dependencies[1].srcStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
		dependencies[1].dstStageMask = VK_PIPELINE_STAGE_BOTTOM_OF_PIPE_BIT;
		dependencies[1].srcAccessMask = VK_ACCESS_COLOR_ATTACHMENT_READ_BIT | VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
		dependencies[1].dstAccessMask = VK_ACCESS_MEMORY_READ_BIT;
		dependencies[1].dependencyFlags = VK_DEPENDENCY_BY_REGION_BIT;

		VkRenderPassCreateInfo renderPassCI = vks::initializers::renderPassCreateInfo();
		renderPassCI.attachmentCount = 1;
		renderPassCI.pAttachments = &attDesc;
		renderPassCI.subpassCount = 1;
		renderPassCI.pSubpasses = &subpassDescription;
		renderPassCI.dependencyCount = 2;
		renderPassCI.pDependencies = dependencies.data();
		VkRenderPass renderpass;
		VK_CHECK_RESULT(vkCreateRenderPass(device, &renderPassCI, nullptr, &renderpass));

		{
			VkImageCreateInfo imageCreateInfo = vks::initializers::imageCreateInfo();
			imageCreateInfo.imageType = VK_IMAGE_TYPE_2D;
			imageCreateInfo.format = format;
			imageCreateInfo.extent.width = dim;
			imageCreateInfo.extent.height = dim;
			imageCreateInfo.extent.depth = 1;
			imageCreateInfo.mipLevels = 1;
			imageCreateInfo.arrayLayers = 1;
			imageCreateInfo.samples = VK_SAMPLE_COUNT_1_BIT;
			imageCreateInfo.tiling = VK_IMAGE_TILING_OPTIMAL;
			imageCreateInfo.initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;
			imageCreateInfo.usage = VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_TRANSFER_SRC_BIT;
			imageCreateInfo.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
			VK_CHECK_RESULT(vkCreateImage(device, &imageCreateInfo, nullptr, &offscreen.image))

			VkMemoryAllocateInfo memAlloc = vks::initializers::memoryAllocateInfo();
			VkMemoryRequirements memReqs;
			vkGetImageMemoryRequirements(device, offscreen.image, &memReqs);
			memAlloc.allocationSize = memReqs.size;
			memAlloc.memoryTypeIndex = vulkanDevice->getMemoryType(memReqs.memoryTypeBits, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT);
			VK_CHECK_RESULT(vkAllocateMemory(device, &memAlloc, nullptr, &offscreen.memory))
			VK_CHECK_RESULT(vkBindImageMemory(device, offscreen.image, offscreen.memory, 0))

			VkImageViewCreateInfo colorImageView = vks::initializers::imageViewCreateInfo();
			colorImageView.viewType = VK_IMAGE_VIEW_TYPE_2D;
			colorImageView.format = format;
			colorImageView.flags = 0;
			colorImageView.subresourceRange = {};
			colorImageView.subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
			colorImageView.subresourceRange.baseMipLevel = 0;
			colorImageView.subresourceRange.levelCount = 1;
			colorImageView.subresourceRange.baseArrayLayer = 0;
			colorImageView.subresourceRange.layerCount = 1;
			colorImageView.image = offscreen.image;
			VK_CHECK_RESULT(vkCreateImageView(device, &colorImageView, nullptr, &offscreen.view))

			VkFramebufferCreateInfo fbufCreateInfo = vks::initializers::framebufferCreateInfo();
			fbufCreateInfo.renderPass = renderpass;
			fbufCreateInfo.attachmentCount = 1;
			fbufCreateInfo.pAttachments = &offscreen.view;
			fbufCreateInfo.width = dim;
			fbufCreateInfo.height = dim;
			fbufCreateInfo.layers = 1;
			VK_CHECK_RESULT(vkCreateFramebuffer(device, &fbufCreateInfo, nullptr, &offscreen.framebuffer))

			VkCommandBuffer layoutCmd = vulkanDevice->createCommandBuffer(VK_COMMAND_BUFFER_LEVEL_PRIMARY, true);
			vks::tools::setImageLayout(
				layoutCmd,
				offscreen.image,
				VK_IMAGE_ASPECT_COLOR_BIT,
				VK_IMAGE_LAYOUT_UNDEFINED,
				VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL);
			vulkanDevice->flushCommandBuffer(layoutCmd, queue, true);
		}
		VkDescriptorSetLayout descriptorsetlayout;
		std::vector<VkDescriptorSetLayoutBinding> setLayoutBindings =
			{
				vks::initializers::descriptorSetLayoutBinding(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, VK_SHADER_STAGE_FRAGMENT_BIT, 0),
			};
		VkDescriptorSetLayoutCreateInfo descriptorsetlayoutCI = vks::initializers::descriptorSetLayoutCreateInfo(setLayoutBindings);
		VK_CHECK_RESULT(vkCreateDescriptorSetLayout(device, &descriptorsetlayoutCI, nullptr, &descriptorsetlayout));
		
		std::vector<VkDescriptorPoolSize> poolSizes = { vks::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 1) };
		VkDescriptorPoolCreateInfo descriptorPoolCI = vks::initializers::descriptorPoolCreateInfo(poolSizes, 2);
		VkDescriptorPool descriptorpool;
		VK_CHECK_RESULT(vkCreateDescriptorPool(device, &descriptorPoolCI, nullptr, &descriptorpool));

		VkDescriptorSet descriptorset;
		VkDescriptorSetAllocateInfo allocInfo =	vks::initializers::descriptorSetAllocateInfo(descriptorpool, &descriptorsetlayout, 1);
		VK_CHECK_RESULT(vkAllocateDescriptorSets(device, &allocInfo, &descriptorset));
		VkWriteDescriptorSet writeDescriptorSet = vks::initializers::writeDescriptorSet(descriptorset, VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 0, &ibltextures.skyboxCube.descriptor);
		vkUpdateDescriptorSets(device, 1, &writeDescriptorSet, 0, nullptr);



		VkPipelineLayout pipelinelayout;
		std::vector<VkPushConstantRange> pushConstantRanges =
			{
				vks::initializers::pushConstantRange(VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT, sizeof(IrradiancePushBlock), 0)
			};
		VkPipelineLayoutCreateInfo pipelineLayoutCI = vks::initializers::pipelineLayoutCreateInfo(&descriptorsetlayout, 1);
		pipelineLayoutCI.pushConstantRangeCount = 1;
		pipelineLayoutCI.pPushConstantRanges = pushConstantRanges.data();
		VK_CHECK_RESULT(vkCreatePipelineLayout(device, &pipelineLayoutCI, nullptr, &pipelinelayout));

		//Pipeline Setting
		VkPipelineInputAssemblyStateCreateInfo inputAssemblyState = vks::initializers::pipelineInputAssemblyStateCreateInfo(VK_PRIMITIVE_TOPOLOGY_TRIANGLE_LIST, 0, VK_FALSE);
		VkPipelineRasterizationStateCreateInfo rasterizationState = vks::initializers::pipelineRasterizationStateCreateInfo(VK_POLYGON_MODE_FILL, VK_CULL_MODE_NONE, VK_FRONT_FACE_COUNTER_CLOCKWISE);
		VkPipelineColorBlendAttachmentState blendAttachmentState = vks::initializers::pipelineColorBlendAttachmentState(0xf, VK_FALSE);
		VkPipelineColorBlendStateCreateInfo colorBlendState = vks::initializers::pipelineColorBlendStateCreateInfo(1, &blendAttachmentState);
		VkPipelineDepthStencilStateCreateInfo depthStencilState = vks::initializers::pipelineDepthStencilStateCreateInfo(VK_FALSE, VK_FALSE, VK_COMPARE_OP_LESS_OR_EQUAL);
		VkPipelineViewportStateCreateInfo viewportState = vks::initializers::pipelineViewportStateCreateInfo(1, 1);
		VkPipelineMultisampleStateCreateInfo multisampleState = vks::initializers::pipelineMultisampleStateCreateInfo(VK_SAMPLE_COUNT_1_BIT);
		std::vector<VkDynamicState> dynamicStateEnables = { VK_DYNAMIC_STATE_VIEWPORT, VK_DYNAMIC_STATE_SCISSOR };
		VkPipelineDynamicStateCreateInfo dynamicState = vks::initializers::pipelineDynamicStateCreateInfo(dynamicStateEnables);
		std::array<VkPipelineShaderStageCreateInfo, 2> shaderStages;

		const std::vector<VkVertexInputBindingDescription> vertexInputBindings = 
		{
			vks::initializers::vertexInputBindingDescription(0, sizeof(VulkanglTFModel::Vertex), VK_VERTEX_INPUT_RATE_VERTEX),
		};

		const std::vector<VkVertexInputAttributeDescription> vertexInputAttributes = {
			vks::initializers::vertexInputAttributeDescription(0, 0, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, pos)),	// Location 0: Position
			//vks::initializers::vertexInputAttributeDescription(0, 1, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, normal)),// Location 1: Normal
			//vks::initializers::vertexInputAttributeDescription(0, 2, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, uv)),	// Location 2: Texture coordinates
			//vks::initializers::vertexInputAttributeDescription(0, 3, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, color)),	// Location 3: Color
			//vks::initializers::vertexInputAttributeDescription(0, 4, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, tangent)), // Location 4 : Tangent
		};
		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();

		VkGraphicsPipelineCreateInfo pipelineCI = vks::initializers::pipelineCreateInfo(pipelinelayout, renderpass);
		pipelineCI.pInputAssemblyState = &inputAssemblyState;
		pipelineCI.pRasterizationState = &rasterizationState;
		pipelineCI.pColorBlendState = &colorBlendState;
		pipelineCI.pMultisampleState = &multisampleState;
		pipelineCI.pViewportState = &viewportState;
		pipelineCI.pDepthStencilState = &depthStencilState;
		pipelineCI.pDynamicState = &dynamicState;
		pipelineCI.stageCount = 2;
		pipelineCI.pStages = shaderStages.data();
		pipelineCI.renderPass = renderpass;

		pipelineCI.pVertexInputState = &vertexInputStateCI;
		shaderStages[0] = loadShader(getHomeworkShadersPath() + "homework1/filtercube.vert.spv", VK_SHADER_STAGE_VERTEX_BIT);
		shaderStages[1] = loadShader(getHomeworkShadersPath() + "homework1/irradiancecube.frag.spv", VK_SHADER_STAGE_FRAGMENT_BIT);
		VkPipeline pipeline;
		VK_CHECK_RESULT(vkCreateGraphicsPipelines(device, pipelineCache, 1, &pipelineCI, nullptr, &pipeline));

		//Render
		VkClearValue clearValues[1];
		clearValues[0].color = { { 0.0f, 0.0f, 0.2f, 0.0f } };
		VkRenderPassBeginInfo renderPassBeginInfo = vks::initializers::renderPassBeginInfo();
		renderPassBeginInfo.renderPass = renderpass;
		renderPassBeginInfo.framebuffer = offscreen.framebuffer;
		renderPassBeginInfo.renderArea.extent.width = dim;
		renderPassBeginInfo.renderArea.extent.height = dim;
		renderPassBeginInfo.clearValueCount = 1;
		renderPassBeginInfo.pClearValues = clearValues;

		//six face in cube map
		std::vector<glm::mat4> matrices = {
			// POSITIVE_X
			glm::rotate(glm::rotate(glm::mat4(1.0f), glm::radians(90.0f), glm::vec3(0.0f, 1.0f, 0.0f)), glm::radians(180.0f), glm::vec3(1.0f, 0.0f, 0.0f)),
			// NEGATIVE_X
			glm::rotate(glm::rotate(glm::mat4(1.0f), glm::radians(-90.0f), glm::vec3(0.0f, 1.0f, 0.0f)), glm::radians(180.0f), glm::vec3(1.0f, 0.0f, 0.0f)),
			// POSITIVE_Y
			glm::rotate(glm::mat4(1.0f), glm::radians(-90.0f), glm::vec3(1.0f, 0.0f, 0.0f)),
			// NEGATIVE_Y
			glm::rotate(glm::mat4(1.0f), glm::radians(90.0f), glm::vec3(1.0f, 0.0f, 0.0f)),
			// POSITIVE_Z
			glm::rotate(glm::mat4(1.0f), glm::radians(180.0f), glm::vec3(1.0f, 0.0f, 0.0f)),
			// NEGATIVE_Z
			glm::rotate(glm::mat4(1.0f), glm::radians(180.0f), glm::vec3(0.0f, 0.0f, 1.0f)),
		};
		VkCommandBuffer cmdBuf = vulkanDevice->createCommandBuffer(VK_COMMAND_BUFFER_LEVEL_PRIMARY, true);
		VkViewport viewport = vks::initializers::viewport((float)dim, (float)dim, 0.0f, 1.0f);
		VkRect2D scissor = vks::initializers::rect2D(dim, dim, 0, 0);
		
		vkCmdSetViewport(cmdBuf, 0, 1, &viewport);
		vkCmdSetScissor(cmdBuf, 0, 1, &scissor);
		
		VkImageSubresourceRange subresourceRange = {};
		subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
		subresourceRange.baseMipLevel = 0;
		subresourceRange.levelCount = numMips;
		subresourceRange.layerCount = 6;
		
		vks::tools::setImageLayout(
		cmdBuf,
		ibltextures.irradianceCube.image,
		VK_IMAGE_LAYOUT_UNDEFINED,
		VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
		subresourceRange);

		for(uint32_t m = 0; m < numMips; ++m)
		{
			for(uint32_t f = 0; f < 6; ++f)
			{
				viewport.width = static_cast<float>(dim * std::pow(0.5f, m));
				viewport.height = static_cast<float>(dim * std::pow(0.5f, m));
				vkCmdSetViewport(cmdBuf, 0, 1, &viewport);
				// Render scene from cube face's point of view
				vkCmdBeginRenderPass(cmdBuf, &renderPassBeginInfo, VK_SUBPASS_CONTENTS_INLINE);
				irradiancePushBlock.mvp = glm::perspective((float)(M_PI / 2.0), 1.0f, 0.1f, 512.0f) * matrices[f];
				vkCmdPushConstants(cmdBuf, pipelinelayout, VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT, 0, sizeof(IrradiancePushBlock), &irradiancePushBlock);
				
				vkCmdBindPipeline(cmdBuf, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline);
				vkCmdBindDescriptorSets(cmdBuf, VK_PIPELINE_BIND_POINT_GRAPHICS, pipelinelayout, 0, 1, &descriptorset, 0, NULL);
				skyboxModel.draw(cmdBuf, pipelinelayout, false);
				vkCmdEndRenderPass(cmdBuf);

				vks::tools::setImageLayout(
					cmdBuf,
					offscreen.image,
					VK_IMAGE_ASPECT_COLOR_BIT,
					VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL,
					VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL);

				VkImageCopy copyRegion = {};
				copyRegion.srcSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
				copyRegion.srcSubresource.layerCount = 1;
				copyRegion.srcSubresource.mipLevel = 0;
				copyRegion.srcSubresource.baseArrayLayer = 0;

				copyRegion.dstSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
				copyRegion.dstSubresource.layerCount = 1;
				copyRegion.dstSubresource.mipLevel = m;
				copyRegion.dstSubresource.baseArrayLayer = f;

				copyRegion.extent.width = static_cast<uint32_t>(viewport.width);
				copyRegion.extent.height = static_cast<uint32_t>(viewport.height);
				copyRegion.extent.depth = 1;

				vkCmdCopyImage(
					cmdBuf,
					offscreen.image,
					VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL,
					ibltextures.irradianceCube.image,
					VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
					1,
					&copyRegion);
				vks::tools::setImageLayout(cmdBuf,
					offscreen.image,
					VK_IMAGE_ASPECT_COLOR_BIT,
					VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL,
					VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL
					);
			}
		}

		vks::tools::setImageLayout(cmdBuf,
			ibltextures.irradianceCube.image,
			VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
			VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL,
			subresourceRange);
		vulkanDevice->flushCommandBuffer(cmdBuf, queue);

		vkDestroyRenderPass(device, renderpass, nullptr);
		vkDestroyFramebuffer(device, offscreen.framebuffer, nullptr);
		vkFreeMemory(device, offscreen.memory, nullptr);
		vkDestroyImageView(device, offscreen.view, nullptr);
		vkDestroyImage(device, offscreen.image, nullptr);
		vkDestroyDescriptorPool(device, descriptorpool, nullptr);
		vkDestroyDescriptorSetLayout(device, descriptorsetlayout, nullptr);
		vkDestroyPipeline(device, pipeline, nullptr);
		vkDestroyPipelineLayout(device, pipelinelayout, nullptr);

		auto tEnd = std::chrono::high_resolution_clock::now();
		auto tDiff = std::chrono::duration<double, std::milli>(tEnd - tStart).count();
		std::cout << "Generating irradiance cube with " << numMips << " mip levels took " << tDiff << " ms" << std::endl;
	}

	void VulkanExample::GeneratePrefilteredCubemap()
	{
		auto tStart = std::chrono::high_resolution_clock::now();

		constexpr VkFormat format = VK_FORMAT_R32G32B32A32_SFLOAT;
		constexpr int32_t dim = 512;
		const uint32_t numMips = static_cast<uint32_t>(floor(log2(dim))) + 1;

		VkImageCreateInfo imageCI = vks::initializers::imageCreateInfo();
		imageCI.imageType = VK_IMAGE_TYPE_2D;
		imageCI.format = format;
		imageCI.extent.width = dim;
		imageCI.extent.height = dim;
		imageCI.extent.depth = 1;
		imageCI.mipLevels = numMips;
		imageCI.arrayLayers = 6;
		imageCI.samples = VK_SAMPLE_COUNT_1_BIT;
		imageCI.tiling = VK_IMAGE_TILING_OPTIMAL;
		imageCI.usage = VK_IMAGE_USAGE_SAMPLED_BIT | VK_IMAGE_USAGE_TRANSFER_DST_BIT;
		imageCI.flags = VK_IMAGE_CREATE_CUBE_COMPATIBLE_BIT;

		VK_CHECK_RESULT(vkCreateImage(device, &imageCI, nullptr, &ibltextures.prefilteredCube.image));
		VkMemoryAllocateInfo memAlloc = vks::initializers::memoryAllocateInfo();
		VkMemoryRequirements memReqs;
		vkGetImageMemoryRequirements(device, ibltextures.prefilteredCube.image, &memReqs);
		memAlloc.allocationSize = memReqs.size;
		memAlloc.memoryTypeIndex = vulkanDevice->getMemoryType(memReqs.memoryTypeBits, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT);
		VK_CHECK_RESULT(vkAllocateMemory(device, &memAlloc, nullptr, &ibltextures.prefilteredCube.deviceMemory));
		VK_CHECK_RESULT(vkBindImageMemory(device, ibltextures.prefilteredCube.image, ibltextures.prefilteredCube.deviceMemory, 0));

		// Image view
		VkImageViewCreateInfo viewCI = vks::initializers::imageViewCreateInfo();
		viewCI.viewType = VK_IMAGE_VIEW_TYPE_CUBE;
		viewCI.format = format;
		viewCI.subresourceRange = {};
		viewCI.subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
		viewCI.subresourceRange.levelCount = numMips;
		viewCI.subresourceRange.layerCount = 6;
		viewCI.image = ibltextures.prefilteredCube.image;
		VK_CHECK_RESULT(vkCreateImageView(device, &viewCI, nullptr, &ibltextures.prefilteredCube.view));

		// Sampler
		VkSamplerCreateInfo samplerCI = vks::initializers::samplerCreateInfo();
		samplerCI.magFilter = VK_FILTER_LINEAR;
		samplerCI.minFilter = VK_FILTER_LINEAR;
		samplerCI.mipmapMode = VK_SAMPLER_MIPMAP_MODE_LINEAR;
		samplerCI.addressModeU = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
		samplerCI.addressModeV = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
		samplerCI.addressModeW = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
		samplerCI.minLod = 0.0f;
		samplerCI.maxLod = static_cast<float>(numMips);
		samplerCI.borderColor = VK_BORDER_COLOR_FLOAT_OPAQUE_WHITE;
		VK_CHECK_RESULT(vkCreateSampler(device, &samplerCI, nullptr, &ibltextures.prefilteredCube.sampler));

		ibltextures.prefilteredCube.descriptor.imageView = ibltextures.prefilteredCube.view;
		ibltextures.prefilteredCube.descriptor.sampler = ibltextures.prefilteredCube.sampler;
		ibltextures.prefilteredCube.descriptor.imageLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
		ibltextures.prefilteredCube.device = vulkanDevice;

		// FB, Att, RP, Pipe, etc.
		VkAttachmentDescription attDesc = {};
		// Color attachment
		attDesc.format = format;
		attDesc.samples = VK_SAMPLE_COUNT_1_BIT;
		attDesc.loadOp = VK_ATTACHMENT_LOAD_OP_CLEAR;
		attDesc.storeOp = VK_ATTACHMENT_STORE_OP_STORE;
		attDesc.stencilLoadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE;
		attDesc.stencilStoreOp = VK_ATTACHMENT_STORE_OP_DONT_CARE;
		attDesc.initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;
		attDesc.finalLayout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
		VkAttachmentReference colorReference = { 0, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL };

		VkSubpassDescription subpassDescription = {};
		subpassDescription.pipelineBindPoint = VK_PIPELINE_BIND_POINT_GRAPHICS;
		subpassDescription.colorAttachmentCount = 1;
		subpassDescription.pColorAttachments = &colorReference;

		// Use subpass dependencies for layout transitions
		std::array<VkSubpassDependency, 2> dependencies;
		dependencies[0].srcSubpass = VK_SUBPASS_EXTERNAL;
		dependencies[0].dstSubpass = 0;
		dependencies[0].srcStageMask = VK_PIPELINE_STAGE_BOTTOM_OF_PIPE_BIT;
		dependencies[0].dstStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
		dependencies[0].srcAccessMask = VK_ACCESS_MEMORY_READ_BIT;
		dependencies[0].dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_READ_BIT | VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
		dependencies[0].dependencyFlags = VK_DEPENDENCY_BY_REGION_BIT;
		dependencies[1].srcSubpass = 0;
		dependencies[1].dstSubpass = VK_SUBPASS_EXTERNAL;
		dependencies[1].srcStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
		dependencies[1].dstStageMask = VK_PIPELINE_STAGE_BOTTOM_OF_PIPE_BIT;
		dependencies[1].srcAccessMask = VK_ACCESS_COLOR_ATTACHMENT_READ_BIT | VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
		dependencies[1].dstAccessMask = VK_ACCESS_MEMORY_READ_BIT;
		dependencies[1].dependencyFlags = VK_DEPENDENCY_BY_REGION_BIT;

		// Renderpass
		VkRenderPassCreateInfo renderPassCI = vks::initializers::renderPassCreateInfo();
		renderPassCI.attachmentCount = 1;
		renderPassCI.pAttachments = &attDesc;
		renderPassCI.subpassCount = 1;
		renderPassCI.pSubpasses = &subpassDescription;
		renderPassCI.dependencyCount = 2;
		renderPassCI.pDependencies = dependencies.data();
		VkRenderPass renderpass;
		VK_CHECK_RESULT(vkCreateRenderPass(device, &renderPassCI, nullptr, &renderpass));

		struct {
			VkImage image;
			VkImageView view;
			VkDeviceMemory memory;
			VkFramebuffer framebuffer;
		} offscreen;
		//framebuffer
		{
			// Color attachment
			VkImageCreateInfo imageCreateInfo = vks::initializers::imageCreateInfo();
			imageCreateInfo.imageType = VK_IMAGE_TYPE_2D;
			imageCreateInfo.format = format;
			imageCreateInfo.extent.width = dim;
			imageCreateInfo.extent.height = dim;
			imageCreateInfo.extent.depth = 1;
			imageCreateInfo.mipLevels = 1;
			imageCreateInfo.arrayLayers = 1;
			imageCreateInfo.samples = VK_SAMPLE_COUNT_1_BIT;
			imageCreateInfo.tiling = VK_IMAGE_TILING_OPTIMAL;
			imageCreateInfo.initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;
			imageCreateInfo.usage = VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_TRANSFER_SRC_BIT;
			imageCreateInfo.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
			VK_CHECK_RESULT(vkCreateImage(device, &imageCreateInfo, nullptr, &offscreen.image));

			VkMemoryAllocateInfo memAlloc = vks::initializers::memoryAllocateInfo();
			VkMemoryRequirements memReqs;
			vkGetImageMemoryRequirements(device, offscreen.image, &memReqs);
			memAlloc.allocationSize = memReqs.size;
			memAlloc.memoryTypeIndex = vulkanDevice->getMemoryType(memReqs.memoryTypeBits, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT);
			VK_CHECK_RESULT(vkAllocateMemory(device, &memAlloc, nullptr, &offscreen.memory));
			VK_CHECK_RESULT(vkBindImageMemory(device, offscreen.image, offscreen.memory, 0));

			VkImageViewCreateInfo colorImageView = vks::initializers::imageViewCreateInfo();
			colorImageView.viewType = VK_IMAGE_VIEW_TYPE_2D;
			colorImageView.format = format;
			colorImageView.flags = 0;
			colorImageView.subresourceRange = {};
			colorImageView.subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
			colorImageView.subresourceRange.baseMipLevel = 0;
			colorImageView.subresourceRange.levelCount = 1;
			colorImageView.subresourceRange.baseArrayLayer = 0;
			colorImageView.subresourceRange.layerCount = 1;
			colorImageView.image = offscreen.image;
			VK_CHECK_RESULT(vkCreateImageView(device, &colorImageView, nullptr, &offscreen.view));

			VkFramebufferCreateInfo fbufCreateInfo = vks::initializers::framebufferCreateInfo();
			fbufCreateInfo.renderPass = renderpass;
			fbufCreateInfo.attachmentCount = 1;
			fbufCreateInfo.pAttachments = &offscreen.view;
			fbufCreateInfo.width = dim;
			fbufCreateInfo.height = dim;
			fbufCreateInfo.layers = 1;
			VK_CHECK_RESULT(vkCreateFramebuffer(device, &fbufCreateInfo, nullptr, &offscreen.framebuffer));

			VkCommandBuffer layoutCmd = vulkanDevice->createCommandBuffer(VK_COMMAND_BUFFER_LEVEL_PRIMARY, true);
			vks::tools::setImageLayout(
				layoutCmd,
				offscreen.image,
				VK_IMAGE_ASPECT_COLOR_BIT,
				VK_IMAGE_LAYOUT_UNDEFINED,
				VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL);
			vulkanDevice->flushCommandBuffer(layoutCmd, queue, true);
		}

	// Descriptors
	VkDescriptorSetLayout descriptorsetlayout;
	std::vector<VkDescriptorSetLayoutBinding> setLayoutBindings = {
		vks::initializers::descriptorSetLayoutBinding(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, VK_SHADER_STAGE_FRAGMENT_BIT, 0),
	};
	VkDescriptorSetLayoutCreateInfo descriptorsetlayoutCI = vks::initializers::descriptorSetLayoutCreateInfo(setLayoutBindings);
	VK_CHECK_RESULT(vkCreateDescriptorSetLayout(device, &descriptorsetlayoutCI, nullptr, &descriptorsetlayout));

	// Descriptor Pool
	std::vector<VkDescriptorPoolSize> poolSizes = { vks::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 1) };
	VkDescriptorPoolCreateInfo descriptorPoolCI = vks::initializers::descriptorPoolCreateInfo(poolSizes, 2);
	VkDescriptorPool descriptorpool;
	VK_CHECK_RESULT(vkCreateDescriptorPool(device, &descriptorPoolCI, nullptr, &descriptorpool));

	VkDescriptorSet descriptorset;
	VkDescriptorSetAllocateInfo allocInfo = vks::initializers::descriptorSetAllocateInfo(descriptorpool, &descriptorsetlayout, 1);
	VK_CHECK_RESULT(vkAllocateDescriptorSets(device, &allocInfo, &descriptorset));
	VkWriteDescriptorSet writeDescriptorSet = vks::initializers::writeDescriptorSet(descriptorset, VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 0, &ibltextures.skyboxCube.descriptor);
	vkUpdateDescriptorSets(device, 1, &writeDescriptorSet, 0, nullptr);

	struct PushBlock {
		glm::mat4 mvp;
		float roughness;
		uint32_t numSamples = 32u;
	} pushBlock;

	std::vector<VkPushConstantRange> pushConstantRanges = {
		vks::initializers::pushConstantRange(VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT, sizeof(PushBlock), 0),
	};
	VkPipelineLayoutCreateInfo pipelineLayoutCI = vks::initializers::pipelineLayoutCreateInfo(&descriptorsetlayout, 1);
	pipelineLayoutCI.pushConstantRangeCount = 1;
	pipelineLayoutCI.pPushConstantRanges = pushConstantRanges.data();
	VkPipelineLayout pipelinelayout;
	VK_CHECK_RESULT(vkCreatePipelineLayout(device, &pipelineLayoutCI, nullptr, &pipelinelayout));

	VkPipelineInputAssemblyStateCreateInfo inputAssemblyState = vks::initializers::pipelineInputAssemblyStateCreateInfo(VK_PRIMITIVE_TOPOLOGY_TRIANGLE_LIST, 0, VK_FALSE);
	VkPipelineRasterizationStateCreateInfo rasterizationState = vks::initializers::pipelineRasterizationStateCreateInfo(VK_POLYGON_MODE_FILL, VK_CULL_MODE_NONE, VK_FRONT_FACE_COUNTER_CLOCKWISE);
	VkPipelineColorBlendAttachmentState blendAttachmentState = vks::initializers::pipelineColorBlendAttachmentState(0xf, VK_FALSE);
	VkPipelineColorBlendStateCreateInfo colorBlendState = vks::initializers::pipelineColorBlendStateCreateInfo(1, &blendAttachmentState);
	VkPipelineDepthStencilStateCreateInfo depthStencilState = vks::initializers::pipelineDepthStencilStateCreateInfo(VK_FALSE, VK_FALSE, VK_COMPARE_OP_LESS_OR_EQUAL);
	VkPipelineViewportStateCreateInfo viewportState = vks::initializers::pipelineViewportStateCreateInfo(1, 1);
	VkPipelineMultisampleStateCreateInfo multisampleState = vks::initializers::pipelineMultisampleStateCreateInfo(VK_SAMPLE_COUNT_1_BIT);
	std::vector<VkDynamicState> dynamicStateEnables = { VK_DYNAMIC_STATE_VIEWPORT, VK_DYNAMIC_STATE_SCISSOR };
	VkPipelineDynamicStateCreateInfo dynamicState = vks::initializers::pipelineDynamicStateCreateInfo(dynamicStateEnables);
	std::array<VkPipelineShaderStageCreateInfo, 2> shaderStages;

	const std::vector<VkVertexInputBindingDescription> vertexInputBindings =
	{
		vks::initializers::vertexInputBindingDescription(0, sizeof(VulkanglTFModel::Vertex), VK_VERTEX_INPUT_RATE_VERTEX),
	};

	const std::vector<VkVertexInputAttributeDescription> vertexInputAttributes = {
		vks::initializers::vertexInputAttributeDescription(0, 0, VK_FORMAT_R32G32B32_SFLOAT, offsetof(VulkanglTFModel::Vertex, pos)),	// Location 0: Position
	};
	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();

	VkGraphicsPipelineCreateInfo pipelineCI = vks::initializers::pipelineCreateInfo(pipelinelayout, renderpass);
	pipelineCI.pInputAssemblyState = &inputAssemblyState;
	pipelineCI.pRasterizationState = &rasterizationState;
	pipelineCI.pColorBlendState = &colorBlendState;
	pipelineCI.pMultisampleState = &multisampleState;
	pipelineCI.pViewportState = &viewportState;
	pipelineCI.pDepthStencilState = &depthStencilState;
	pipelineCI.pDynamicState = &dynamicState;
	pipelineCI.stageCount = 2;
	pipelineCI.pStages = shaderStages.data();
	pipelineCI.renderPass = renderpass;
	pipelineCI.pVertexInputState = &vertexInputStateCI;

	shaderStages[0] = loadShader(getHomeworkShadersPath() + "homework1/filtercube.vert.spv", VK_SHADER_STAGE_VERTEX_BIT);
	shaderStages[1] = loadShader(getHomeworkShadersPath() + "homework1/prefilterenvmap.frag.spv", VK_SHADER_STAGE_FRAGMENT_BIT);

	VkPipeline pipeline;
	VK_CHECK_RESULT(vkCreateGraphicsPipelines(device, pipelineCache, 1, &pipelineCI, nullptr, &pipeline));

	//Render & build cmd
	VkClearValue clearValues[1];
	clearValues[0].color = { { 0.0f, 0.0f, 0.2f, 0.0f } };

	VkRenderPassBeginInfo renderPassBeginInfo = vks::initializers::renderPassBeginInfo();
	// Reuse render pass from example pass
	renderPassBeginInfo.renderPass = renderpass;
	renderPassBeginInfo.framebuffer = offscreen.framebuffer;
	renderPassBeginInfo.renderArea.extent.width = dim;
	renderPassBeginInfo.renderArea.extent.height = dim;
	renderPassBeginInfo.clearValueCount = 1;
	renderPassBeginInfo.pClearValues = clearValues;

	std::vector<glm::mat4> matrices = {
		// POSITIVE_X
		glm::rotate(glm::rotate(glm::mat4(1.0f), glm::radians(90.0f), glm::vec3(0.0f, 1.0f, 0.0f)), glm::radians(180.0f), glm::vec3(1.0f, 0.0f, 0.0f)),
		// NEGATIVE_X
		glm::rotate(glm::rotate(glm::mat4(1.0f), glm::radians(-90.0f), glm::vec3(0.0f, 1.0f, 0.0f)), glm::radians(180.0f), glm::vec3(1.0f, 0.0f, 0.0f)),
		// POSITIVE_Y
		glm::rotate(glm::mat4(1.0f), glm::radians(-90.0f), glm::vec3(1.0f, 0.0f, 0.0f)),
		// NEGATIVE_Y
		glm::rotate(glm::mat4(1.0f), glm::radians(90.0f), glm::vec3(1.0f, 0.0f, 0.0f)),
		// POSITIVE_Z
		glm::rotate(glm::mat4(1.0f), glm::radians(180.0f), glm::vec3(1.0f, 0.0f, 0.0f)),
		// NEGATIVE_Z
		glm::rotate(glm::mat4(1.0f), glm::radians(180.0f), glm::vec3(0.0f, 0.0f, 1.0f)),
	};
	VkCommandBuffer cmdBuf = vulkanDevice->createCommandBuffer(VK_COMMAND_BUFFER_LEVEL_PRIMARY, true);

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

	vkCmdSetViewport(cmdBuf, 0, 1, &viewport);
	vkCmdSetScissor(cmdBuf, 0, 1, &scissor);

	VkImageSubresourceRange subresourceRange = {};
	subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
	subresourceRange.baseMipLevel = 0;
	subresourceRange.levelCount = numMips;
	subresourceRange.layerCount = 6;

	vks::tools::setImageLayout(
		cmdBuf,
		ibltextures.prefilteredCube.image,
		VK_IMAGE_LAYOUT_UNDEFINED,
		VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
		subresourceRange);
	
	for (uint32_t m = 0; m < numMips; ++m)
	{
		//mip level according to roughness
		pushBlock.roughness = float(m) / float(numMips - 1);
		for (uint32_t f = 0; f < 6; ++f)
		{
			viewport.width = static_cast<float>(dim * std::pow(0.5f, m));
			viewport.height = static_cast<float>(dim * std::pow(0.5f, m));
			vkCmdSetViewport(cmdBuf, 0, 1, &viewport);
			// Render scene from cube face's point of view
			vkCmdBeginRenderPass(cmdBuf, &renderPassBeginInfo, VK_SUBPASS_CONTENTS_INLINE);

			// Update shader push constant block
			pushBlock.mvp = glm::perspective((float)(M_PI / 2.0), 1.0f, 0.1f, 512.0f) * matrices[f];

			vkCmdPushConstants(cmdBuf, pipelinelayout, VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT, 0, sizeof(PushBlock), &pushBlock);
			vkCmdBindPipeline(cmdBuf, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline);
			vkCmdBindDescriptorSets(cmdBuf, VK_PIPELINE_BIND_POINT_GRAPHICS, pipelinelayout, 0, 1, &descriptorset, 0, nullptr);
			skyboxModel.draw(cmdBuf, pipelinelayout, false);
			vkCmdEndRenderPass(cmdBuf);

			vks::tools::setImageLayout(
				cmdBuf,
				offscreen.image,
				VK_IMAGE_ASPECT_COLOR_BIT,
				VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL,
				VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL);

			VkImageCopy copyRegion{};
			copyRegion.srcSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
			copyRegion.srcSubresource.baseArrayLayer = 0;
			copyRegion.srcSubresource.mipLevel = 0;
			copyRegion.srcSubresource.layerCount = 1;
			copyRegion.srcOffset = { 0, 0, 0 };

			copyRegion.dstSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
			copyRegion.dstSubresource.baseArrayLayer = f;
			copyRegion.dstSubresource.mipLevel = m;
			copyRegion.dstSubresource.layerCount = 1;
			copyRegion.dstOffset = { 0, 0, 0 };

			copyRegion.extent.width = static_cast<uint32_t>(viewport.width);
			copyRegion.extent.height = static_cast<uint32_t>(viewport.height);
			copyRegion.extent.depth = 1;

			vkCmdCopyImage(
				cmdBuf,
				offscreen.image,
				VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL,
				ibltextures.prefilteredCube.image,
				VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
				1,
				&copyRegion);

			//Reset frame buffer image layout
			vks::tools::setImageLayout(
				cmdBuf,
				offscreen.image,
				VK_IMAGE_ASPECT_COLOR_BIT,
				VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL,
				VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL);
		}
	}

	//Set format shader read
	vks::tools::setImageLayout(
		cmdBuf,
		ibltextures.prefilteredCube.image,
		VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
		VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL,
		subresourceRange);

	vulkanDevice->flushCommandBuffer(cmdBuf, queue);

	vkDestroyRenderPass(device, renderpass, nullptr);
	vkDestroyFramebuffer(device, offscreen.framebuffer, nullptr);
	vkFreeMemory(device, offscreen.memory, nullptr);
	vkDestroyImageView(device, offscreen.view, nullptr);
	vkDestroyImage(device, offscreen.image, nullptr);
	vkDestroyDescriptorPool(device, descriptorpool, nullptr);
	vkDestroyDescriptorSetLayout(device, descriptorsetlayout, nullptr);
	vkDestroyPipeline(device, pipeline, nullptr);
	vkDestroyPipelineLayout(device, pipelinelayout, nullptr);

	auto tEnd = std::chrono::high_resolution_clock::now();
	auto tDiff = std::chrono::duration<double, std::milli>(tEnd - tStart).count();
	std::cout << "Generating pre-filtered environment cube with " << numMips << " mip levels took " << tDiff << " ms" << std::endl;
}

	void VulkanExample::GenerateBRDFLUT()
	{
		auto tStart = std::chrono::high_resolution_clock::now();

		constexpr VkFormat format = VK_FORMAT_R16G16_SFLOAT;
		constexpr int32_t dim = 512;

		// Image
		VkImageCreateInfo imageCI = vks::initializers::imageCreateInfo();
		imageCI.imageType = VK_IMAGE_TYPE_2D;
		imageCI.format = format;
		imageCI.extent.width = dim;
		imageCI.extent.height = dim;
		imageCI.extent.depth = 1;
		imageCI.mipLevels = 1;
		imageCI.arrayLayers = 1;
		imageCI.samples = VK_SAMPLE_COUNT_1_BIT;
		imageCI.tiling = VK_IMAGE_TILING_OPTIMAL;
		imageCI.usage = VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT;
		VK_CHECK_RESULT(vkCreateImage(device, &imageCI, nullptr, &ibltextures.lutBrdf.image));
		VkMemoryAllocateInfo memAlloc = vks::initializers::memoryAllocateInfo();
		VkMemoryRequirements memReqs;
		vkGetImageMemoryRequirements(device, ibltextures.lutBrdf.image, &memReqs);
		memAlloc.allocationSize = memReqs.size;
		memAlloc.memoryTypeIndex = vulkanDevice->getMemoryType(memReqs.memoryTypeBits, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT);
		VK_CHECK_RESULT(vkAllocateMemory(device, &memAlloc, nullptr, &ibltextures.lutBrdf.deviceMemory));
		VK_CHECK_RESULT(vkBindImageMemory(device, ibltextures.lutBrdf.image, ibltextures.lutBrdf.deviceMemory, 0));

		// Image view
		VkImageViewCreateInfo viewCI = vks::initializers::imageViewCreateInfo();
		viewCI.viewType = VK_IMAGE_VIEW_TYPE_2D;
		viewCI.format = format;
		viewCI.subresourceRange = {};
		viewCI.subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
		viewCI.subresourceRange.levelCount = 1;
		viewCI.subresourceRange.layerCount = 1;
		viewCI.image = ibltextures.lutBrdf.image;
		VK_CHECK_RESULT(vkCreateImageView(device, &viewCI, nullptr, &ibltextures.lutBrdf.view));

		// Sampler
		VkSamplerCreateInfo samplerCI = vks::initializers::samplerCreateInfo();
		samplerCI.magFilter = VK_FILTER_LINEAR;
		samplerCI.minFilter = VK_FILTER_LINEAR;
		samplerCI.mipmapMode = VK_SAMPLER_MIPMAP_MODE_LINEAR;
		samplerCI.addressModeU = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
		samplerCI.addressModeV = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
		samplerCI.addressModeW = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
		samplerCI.minLod = 0.0f;
		samplerCI.maxLod = 1.0f;
		samplerCI.borderColor = VK_BORDER_COLOR_FLOAT_OPAQUE_WHITE;
		VK_CHECK_RESULT(vkCreateSampler(device, &samplerCI, nullptr, &ibltextures.lutBrdf.sampler));

		ibltextures.lutBrdf.descriptor.imageView = ibltextures.lutBrdf.view;
		ibltextures.lutBrdf.descriptor.sampler = ibltextures.lutBrdf.sampler;
		ibltextures.lutBrdf.descriptor.imageLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
		ibltextures.lutBrdf.device = vulkanDevice;

		// FB, Att, RP, Pipe, etc.
		VkAttachmentDescription attDesc = {};
		// Color attachment
		attDesc.format = format;
		attDesc.samples = VK_SAMPLE_COUNT_1_BIT;
		attDesc.loadOp = VK_ATTACHMENT_LOAD_OP_CLEAR;
		attDesc.storeOp = VK_ATTACHMENT_STORE_OP_STORE;
		attDesc.stencilLoadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE;
		attDesc.stencilStoreOp = VK_ATTACHMENT_STORE_OP_DONT_CARE;
		attDesc.initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;
		attDesc.finalLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
		VkAttachmentReference colorReference = { 0, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL };

		VkSubpassDescription subpassDescription = {};
		subpassDescription.pipelineBindPoint = VK_PIPELINE_BIND_POINT_GRAPHICS;
		subpassDescription.colorAttachmentCount = 1;
		subpassDescription.pColorAttachments = &colorReference;

		// Use subpass dependencies for layout transitions
		std::array<VkSubpassDependency, 2> dependencies;
		dependencies[0].srcSubpass = VK_SUBPASS_EXTERNAL;
		dependencies[0].dstSubpass = 0;
		dependencies[0].srcStageMask = VK_PIPELINE_STAGE_BOTTOM_OF_PIPE_BIT;
		dependencies[0].dstStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
		dependencies[0].srcAccessMask = VK_ACCESS_MEMORY_READ_BIT;
		dependencies[0].dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_READ_BIT | VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
		dependencies[0].dependencyFlags = VK_DEPENDENCY_BY_REGION_BIT;
		dependencies[1].srcSubpass = 0;
		dependencies[1].dstSubpass = VK_SUBPASS_EXTERNAL;
		dependencies[1].srcStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
		dependencies[1].dstStageMask = VK_PIPELINE_STAGE_BOTTOM_OF_PIPE_BIT;
		dependencies[1].srcAccessMask = VK_ACCESS_COLOR_ATTACHMENT_READ_BIT | VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
		dependencies[1].dstAccessMask = VK_ACCESS_MEMORY_READ_BIT;
		dependencies[1].dependencyFlags = VK_DEPENDENCY_BY_REGION_BIT;

		// Create the actual render pass
		VkRenderPassCreateInfo renderPassCI = vks::initializers::renderPassCreateInfo();
		renderPassCI.attachmentCount = 1;
		renderPassCI.pAttachments = &attDesc;
		renderPassCI.subpassCount = 1;
		renderPassCI.pSubpasses = &subpassDescription;
		renderPassCI.dependencyCount = 2;
		renderPassCI.pDependencies = dependencies.data();

		VkRenderPass renderpass;
		VK_CHECK_RESULT(vkCreateRenderPass(device, &renderPassCI, nullptr, &renderpass));

		VkFramebufferCreateInfo framebufferCI = vks::initializers::framebufferCreateInfo();
		framebufferCI.renderPass = renderpass;
		framebufferCI.attachmentCount = 1;
		framebufferCI.pAttachments = &ibltextures.lutBrdf.view;
		framebufferCI.width = dim;
		framebufferCI.height = dim;
		framebufferCI.layers = 1;

		VkFramebuffer framebuffer;
		VK_CHECK_RESULT(vkCreateFramebuffer(device, &framebufferCI, nullptr, &framebuffer));

		// Descriptors
		VkDescriptorSetLayout descriptorsetlayout;
		std::vector<VkDescriptorSetLayoutBinding> setLayoutBindings = {};
		VkDescriptorSetLayoutCreateInfo descriptorsetlayoutCI = vks::initializers::descriptorSetLayoutCreateInfo(setLayoutBindings);
		VK_CHECK_RESULT(vkCreateDescriptorSetLayout(device, &descriptorsetlayoutCI, nullptr, &descriptorsetlayout));

		// Descriptor Pool
		std::vector<VkDescriptorPoolSize> poolSizes = { vks::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 1) };
		VkDescriptorPoolCreateInfo descriptorPoolCI = vks::initializers::descriptorPoolCreateInfo(poolSizes, 2);
		VkDescriptorPool descriptorpool;
		VK_CHECK_RESULT(vkCreateDescriptorPool(device, &descriptorPoolCI, nullptr, &descriptorpool));

		// Descriptor sets
		VkDescriptorSet descriptorset;
		VkDescriptorSetAllocateInfo allocInfo = vks::initializers::descriptorSetAllocateInfo(descriptorpool, &descriptorsetlayout, 1);
		VK_CHECK_RESULT(vkAllocateDescriptorSets(device, &allocInfo, &descriptorset));

		// Pipeline layout
		VkPipelineLayout pipelinelayout;
		VkPipelineLayoutCreateInfo pipelineLayoutCI = vks::initializers::pipelineLayoutCreateInfo(&descriptorsetlayout, 1);
		VK_CHECK_RESULT(vkCreatePipelineLayout(device, &pipelineLayoutCI, nullptr, &pipelinelayout));

		// Pipeline
		VkPipelineInputAssemblyStateCreateInfo inputAssemblyState = vks::initializers::pipelineInputAssemblyStateCreateInfo(VK_PRIMITIVE_TOPOLOGY_TRIANGLE_LIST, 0, VK_FALSE);
		VkPipelineRasterizationStateCreateInfo rasterizationState = vks::initializers::pipelineRasterizationStateCreateInfo(VK_POLYGON_MODE_FILL, VK_CULL_MODE_NONE, VK_FRONT_FACE_COUNTER_CLOCKWISE);
		VkPipelineColorBlendAttachmentState blendAttachmentState = vks::initializers::pipelineColorBlendAttachmentState(0xf, VK_FALSE);
		VkPipelineColorBlendStateCreateInfo colorBlendState = vks::initializers::pipelineColorBlendStateCreateInfo(1, &blendAttachmentState);
		VkPipelineDepthStencilStateCreateInfo depthStencilState = vks::initializers::pipelineDepthStencilStateCreateInfo(VK_FALSE, VK_FALSE, VK_COMPARE_OP_LESS_OR_EQUAL);
		VkPipelineViewportStateCreateInfo viewportState = vks::initializers::pipelineViewportStateCreateInfo(1, 1);
		VkPipelineMultisampleStateCreateInfo multisampleState = vks::initializers::pipelineMultisampleStateCreateInfo(VK_SAMPLE_COUNT_1_BIT);
		std::vector<VkDynamicState> dynamicStateEnables = { VK_DYNAMIC_STATE_VIEWPORT, VK_DYNAMIC_STATE_SCISSOR };
		VkPipelineDynamicStateCreateInfo dynamicState = vks::initializers::pipelineDynamicStateCreateInfo(dynamicStateEnables);
		VkPipelineVertexInputStateCreateInfo emptyInputState = vks::initializers::pipelineVertexInputStateCreateInfo();
		std::array<VkPipelineShaderStageCreateInfo, 2> shaderStages;

		VkGraphicsPipelineCreateInfo pipelineCI = vks::initializers::pipelineCreateInfo(pipelinelayout, renderpass);
		pipelineCI.pInputAssemblyState = &inputAssemblyState;
		pipelineCI.pRasterizationState = &rasterizationState;
		pipelineCI.pColorBlendState = &colorBlendState;
		pipelineCI.pMultisampleState = &multisampleState;
		pipelineCI.pViewportState = &viewportState;
		pipelineCI.pDepthStencilState = &depthStencilState;
		pipelineCI.pDynamicState = &dynamicState;
		pipelineCI.stageCount = 2;
		pipelineCI.pStages = shaderStages.data();
		pipelineCI.pVertexInputState = &emptyInputState;

		// Look-up-table (from BRDF) pipeline
		shaderStages[0] = loadShader(getHomeworkShadersPath() + "homework1/genbrdflut.vert.spv", VK_SHADER_STAGE_VERTEX_BIT);
		shaderStages[1] = loadShader(getHomeworkShadersPath() + "homework1/genbrdflut.frag.spv", VK_SHADER_STAGE_FRAGMENT_BIT);
		VkPipeline pipeline;
		VK_CHECK_RESULT(vkCreateGraphicsPipelines(device, pipelineCache, 1, &pipelineCI, nullptr, &pipeline));

		// Render
		VkClearValue clearValues[1];
		clearValues[0].color = { { 0.0f, 0.0f, 0.0f, 1.0f } };

		VkRenderPassBeginInfo renderPassBeginInfo = vks::initializers::renderPassBeginInfo();
		renderPassBeginInfo.renderPass = renderpass;
		renderPassBeginInfo.renderArea.extent.width = dim;
		renderPassBeginInfo.renderArea.extent.height = dim;
		renderPassBeginInfo.clearValueCount = 1;
		renderPassBeginInfo.pClearValues = clearValues;
		renderPassBeginInfo.framebuffer = framebuffer;

		VkCommandBuffer cmdBuf = vulkanDevice->createCommandBuffer(VK_COMMAND_BUFFER_LEVEL_PRIMARY, true);
		vkCmdBeginRenderPass(cmdBuf, &renderPassBeginInfo, VK_SUBPASS_CONTENTS_INLINE);
		VkViewport viewport = vks::initializers::viewport((float)dim, (float)dim, 0.0f, 1.0f);
		VkRect2D scissor = vks::initializers::rect2D(dim, dim, 0, 0);
		vkCmdSetViewport(cmdBuf, 0, 1, &viewport);
		vkCmdSetScissor(cmdBuf, 0, 1, &scissor);
		vkCmdBindPipeline(cmdBuf, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline);
		vkCmdDraw(cmdBuf, 3, 1, 0, 0);
		vkCmdEndRenderPass(cmdBuf);
		vulkanDevice->flushCommandBuffer(cmdBuf, queue);

		vkQueueWaitIdle(queue);

		vkDestroyPipeline(device, pipeline, nullptr);
		vkDestroyPipelineLayout(device, pipelinelayout, nullptr);
		vkDestroyRenderPass(device, renderpass, nullptr);
		vkDestroyFramebuffer(device, framebuffer, nullptr);
		vkDestroyDescriptorSetLayout(device, descriptorsetlayout, nullptr);
		vkDestroyDescriptorPool(device, descriptorpool, nullptr);

		auto tEnd = std::chrono::high_resolution_clock::now();
		auto tDiff = std::chrono::duration<double, std::milli>(tEnd - tStart).count();
		std::cout << "Generating BRDF LUT took " << tDiff << " ms" << std::endl;
	}
	//----------------------------End Precompute brick------------------------------------------------------------------//
#pragma region pbr render pass setting

	void VulkanExample::createAttachment(
		VkFormat format,
		VkImageUsageFlagBits usage,
		FrameBufferAttachment* attachment,
		uint32_t width,
		uint32_t height)
	{
		VkImageAspectFlags aspectMask = 0;
		VkImageUsageFlags imageUsage = VK_IMAGE_USAGE_TRANSFER_SRC_BIT;
		attachment->format = format;
		if (usage & VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT)
		{
			aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
			imageUsage |= VK_IMAGE_USAGE_SAMPLED_BIT;
		}
		if (usage & VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT)
		{
			aspectMask = VK_IMAGE_ASPECT_DEPTH_BIT;
			if (format >= VK_FORMAT_D16_UNORM_S8_UINT)
				aspectMask |= VK_IMAGE_ASPECT_STENCIL_BIT;
		}

		assert(aspectMask > 0);

		VkImageCreateInfo image = vks::initializers::imageCreateInfo();
		image.imageType = VK_IMAGE_TYPE_2D;
		image.format = format;
		image.extent.width = width;
		image.extent.height = height;
		image.extent.depth = 1;
		image.mipLevels = 1;
		image.arrayLayers = 1;
		image.samples = VK_SAMPLE_COUNT_1_BIT;
		image.tiling = VK_IMAGE_TILING_OPTIMAL;
		image.usage = imageUsage | usage;

		VkMemoryAllocateInfo memAlloc = vks::initializers::memoryAllocateInfo();
		VkMemoryRequirements memReqs;

		VK_CHECK_RESULT(vkCreateImage(device, &image, nullptr, &attachment->image));
		vkGetImageMemoryRequirements(device, attachment->image, &memReqs);
		memAlloc.allocationSize = memReqs.size;
		memAlloc.memoryTypeIndex = vulkanDevice->getMemoryType(memReqs.memoryTypeBits, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT);
		VK_CHECK_RESULT(vkAllocateMemory(device, &memAlloc, nullptr, &attachment->deviceMemory));
		VK_CHECK_RESULT(vkBindImageMemory(device, attachment->image, attachment->deviceMemory, 0));

		VkImageViewCreateInfo imageView = vks::initializers::imageViewCreateInfo();
		imageView.viewType = VK_IMAGE_VIEW_TYPE_2D;
		imageView.format = format;
		imageView.subresourceRange = {};
		imageView.subresourceRange.aspectMask = aspectMask;
		imageView.subresourceRange.baseMipLevel = 0;
		imageView.subresourceRange.levelCount = 1;
		imageView.subresourceRange.baseArrayLayer = 0;
		imageView.subresourceRange.layerCount = 1;
		imageView.image = attachment->image;
		VK_CHECK_RESULT(vkCreateImageView(device, &imageView, nullptr, &attachment->imageView));
	}

#pragma endregion
	// 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)));

		VK_CHECK_RESULT(vulkanDevice->createBuffer(
			VK_BUFFER_USAGE_STORAGE_BUFFER_BIT,
			VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT,
			&shaderData.skinSSBO,
			sizeof(glm::mat4) * glTFModel.nodeCount));

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

		for (auto& material : glTFModel.materials)
		{
			VK_CHECK_RESULT(vulkanDevice->createBuffer(
				VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT,
				VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT,
				&material.materialData.buffer,
				sizeof(VulkanglTFModel::MaterialData::Values),
				&material.materialData.values));
		}

		updateUniformBuffers();
	}

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

	void VulkanExample::prepare()
	{
		VulkanExampleBase::prepare();
		loadAssets();
		GenerateBRDFLUT();
		GenerateIrradianceCubemap();
		GeneratePrefilteredCubemap();
		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->checkBox("NormalMapping", &normalMapping))
			{
			}
			if (overlay->checkBox("ToneMapping", &ToneMapping))
			{
				CreateToneMappingPipeline();
			}
			if (overlay->checkBox("PbrIndirect", &pbrEnabled))
			{
			}
		}

		if (overlay->header("Animation"))
		{
			overlay->checkBox("Pause", &paused);
		}

		if (overlay->header("file"))
		{
			if (overlay->button("select model")) 
			{
				GUIFunction guiFunc{};

				if (guiFunc.openFileFolderDialog())
				{
					MessageBoxW(NULL, guiFunc.filePath, L"File Path", MB_OK);
				}
				else
				{
					std::cerr << "file select error" << std::endl;
				}
			}
		}
	}


VULKAN_EXAMPLE_MAIN()