/*
* Vulkan Example - Cube map texture loading and displaying
*
* Copyright (C) 2016 by Sascha Willems - www.saschawillems.de
*
* This code is licensed under the MIT license (MIT) (http://opensource.org/licenses/MIT)
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <vector>

#define GLM_FORCE_RADIANS
#define GLM_FORCE_DEPTH_ZERO_TO_ONE
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>

#include <gli/gli.hpp>

#include <vulkan/vulkan.h>
#include "vulkanexamplebase.h"
#include "VulkanBuffer.hpp"
#include "VulkanTexture.hpp"
#include "VulkanModel.hpp"

#define VERTEX_BUFFER_BIND_ID 0
#define ENABLE_VALIDATION false

class VulkanExample : public VulkanExampleBase
{
public:
	bool displaySkybox = true;

	vks::Texture cubeMap;

	struct {
		VkPipelineVertexInputStateCreateInfo inputState;
		std::vector<VkVertexInputBindingDescription> bindingDescriptions;
		std::vector<VkVertexInputAttributeDescription> attributeDescriptions;
	} vertices;

	// Vertex layout for the models
	vks::VertexLayout vertexLayout = vks::VertexLayout({
		vks::VERTEX_COMPONENT_POSITION,
		vks::VERTEX_COMPONENT_NORMAL,
		vks::VERTEX_COMPONENT_UV,
	});

	struct Meshes {
		vks::Model skybox;
		std::vector<vks::Model> objects;
		uint32_t objectIndex = 0;
	} models;

	struct {
		vks::Buffer object;
		vks::Buffer skybox;
	} uniformBuffers;

	struct UBOVS {
		glm::mat4 projection;
		glm::mat4 model;
		float lodBias = 0.0f;
	} uboVS;

	struct {
		VkPipeline skybox;
		VkPipeline reflect;
	} pipelines;

	struct {
		VkDescriptorSet object;
		VkDescriptorSet skybox;
	} descriptorSets;

	VkPipelineLayout pipelineLayout;
	VkDescriptorSetLayout descriptorSetLayout;

	VulkanExample() : VulkanExampleBase(ENABLE_VALIDATION)
	{
		zoom = -4.0f;
		rotationSpeed = 0.25f;
		rotation = { -7.25f, -120.0f, 0.0f };
		enableTextOverlay = true;
		title = "Vulkan Example - Cube map";
	}

	~VulkanExample()
	{
		// Clean up used Vulkan resources 
		// Note : Inherited destructor cleans up resources stored in base class

		// Clean up texture resources
		vkDestroyImageView(device, cubeMap.view, nullptr);
		vkDestroyImage(device, cubeMap.image, nullptr);
		vkDestroySampler(device, cubeMap.sampler, nullptr);
		vkFreeMemory(device, cubeMap.deviceMemory, nullptr);

		vkDestroyPipeline(device, pipelines.skybox, nullptr);
		vkDestroyPipeline(device, pipelines.reflect, nullptr);

		vkDestroyPipelineLayout(device, pipelineLayout, nullptr);
		vkDestroyDescriptorSetLayout(device, descriptorSetLayout, nullptr);

		for (auto& model : models.objects) {
			model.destroy();
		}
		models.skybox.destroy();

		uniformBuffers.object.destroy();
		uniformBuffers.skybox.destroy();
	}

	void loadCubemap(std::string filename, VkFormat format, bool forceLinearTiling)
	{
#if defined(__ANDROID__)
		// Textures are stored inside the apk on Android (compressed)
		// So they need to be loaded via the asset manager
		AAsset* asset = AAssetManager_open(androidApp->activity->assetManager, filename.c_str(), AASSET_MODE_STREAMING);
		assert(asset);
		size_t size = AAsset_getLength(asset);
		assert(size > 0);

		void *textureData = malloc(size);
		AAsset_read(asset, textureData, size);
		AAsset_close(asset);

		gli::texture_cube texCube(gli::load((const char*)textureData, size));
#else
		gli::texture_cube texCube(gli::load(filename));
#endif

		assert(!texCube.empty());

		cubeMap.width = texCube.extent().x;
		cubeMap.height = texCube.extent().y;
		cubeMap.mipLevels = texCube.levels();

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

		// Create a host-visible staging buffer that contains the raw image data
		VkBuffer stagingBuffer;
		VkDeviceMemory stagingMemory;

		VkBufferCreateInfo bufferCreateInfo = vks::initializers::bufferCreateInfo();
		bufferCreateInfo.size = texCube.size();
		// This buffer is used as a transfer source for the buffer copy
		bufferCreateInfo.usage = VK_BUFFER_USAGE_TRANSFER_SRC_BIT;
		bufferCreateInfo.sharingMode = VK_SHARING_MODE_EXCLUSIVE;

		VK_CHECK_RESULT(vkCreateBuffer(device, &bufferCreateInfo, nullptr, &stagingBuffer));

		// Get memory requirements for the staging buffer (alignment, memory type bits)
		vkGetBufferMemoryRequirements(device, stagingBuffer, &memReqs);
		memAllocInfo.allocationSize = memReqs.size;
		// Get memory type index for a host visible buffer
		memAllocInfo.memoryTypeIndex = vulkanDevice->getMemoryType(memReqs.memoryTypeBits, VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT);
		VK_CHECK_RESULT(vkAllocateMemory(device, &memAllocInfo, nullptr, &stagingMemory));
		VK_CHECK_RESULT(vkBindBufferMemory(device, stagingBuffer, stagingMemory, 0));

		// Copy texture data into staging buffer
		uint8_t *data;
		VK_CHECK_RESULT(vkMapMemory(device, stagingMemory, 0, memReqs.size, 0, (void **)&data));
		memcpy(data, texCube.data(), texCube.size());
		vkUnmapMemory(device, stagingMemory);

		// Create optimal tiled target image
		VkImageCreateInfo imageCreateInfo = vks::initializers::imageCreateInfo();
		imageCreateInfo.imageType = VK_IMAGE_TYPE_2D;
		imageCreateInfo.format = format;
		imageCreateInfo.mipLevels = cubeMap.mipLevels;
		imageCreateInfo.samples = VK_SAMPLE_COUNT_1_BIT;
		imageCreateInfo.tiling = VK_IMAGE_TILING_OPTIMAL;
		imageCreateInfo.usage = VK_IMAGE_USAGE_SAMPLED_BIT;
		imageCreateInfo.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
		imageCreateInfo.initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;
		imageCreateInfo.extent = { cubeMap.width, cubeMap.height, 1 };
		imageCreateInfo.usage = VK_IMAGE_USAGE_TRANSFER_DST_BIT | VK_IMAGE_USAGE_SAMPLED_BIT;
		// Cube faces count as array layers in Vulkan
		imageCreateInfo.arrayLayers = 6;
		// This flag is required for cube map images
		imageCreateInfo.flags = VK_IMAGE_CREATE_CUBE_COMPATIBLE_BIT;

		VK_CHECK_RESULT(vkCreateImage(device, &imageCreateInfo, nullptr, &cubeMap.image));

		vkGetImageMemoryRequirements(device, cubeMap.image, &memReqs);

		memAllocInfo.allocationSize = memReqs.size;
		memAllocInfo.memoryTypeIndex = vulkanDevice->getMemoryType(memReqs.memoryTypeBits, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT);

		VK_CHECK_RESULT(vkAllocateMemory(device, &memAllocInfo, nullptr, &cubeMap.deviceMemory));
		VK_CHECK_RESULT(vkBindImageMemory(device, cubeMap.image, cubeMap.deviceMemory, 0));

		VkCommandBuffer copyCmd = VulkanExampleBase::createCommandBuffer(VK_COMMAND_BUFFER_LEVEL_PRIMARY, true);

		// Setup buffer copy regions for each face including all of it's miplevels
		std::vector<VkBufferImageCopy> bufferCopyRegions;
		uint32_t offset = 0;

		for (uint32_t face = 0; face < 6; face++)
		{
			for (uint32_t level = 0; level < cubeMap.mipLevels; level++)
			{
				VkBufferImageCopy bufferCopyRegion = {};
				bufferCopyRegion.imageSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
				bufferCopyRegion.imageSubresource.mipLevel = level;
				bufferCopyRegion.imageSubresource.baseArrayLayer = face;
				bufferCopyRegion.imageSubresource.layerCount = 1;
				bufferCopyRegion.imageExtent.width = texCube[face][level].extent().x;
				bufferCopyRegion.imageExtent.height = texCube[face][level].extent().y;
				bufferCopyRegion.imageExtent.depth = 1;
				bufferCopyRegion.bufferOffset = offset;

				bufferCopyRegions.push_back(bufferCopyRegion);

				// Increase offset into staging buffer for next level / face
				offset += texCube[face][level].size();
			}
		}

		// Image barrier for optimal image (target)
		// Set initial layout for all array layers (faces) of the optimal (target) tiled texture
		VkImageSubresourceRange subresourceRange = {};
		subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
		subresourceRange.baseMipLevel = 0;
		subresourceRange.levelCount = cubeMap.mipLevels;
		subresourceRange.layerCount = 6;

		vks::tools::setImageLayout(
			copyCmd,
			cubeMap.image,
			VK_IMAGE_ASPECT_COLOR_BIT,
			VK_IMAGE_LAYOUT_UNDEFINED,
			VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
			subresourceRange);

		// Copy the cube map faces from the staging buffer to the optimal tiled image
		vkCmdCopyBufferToImage(
			copyCmd,
			stagingBuffer,
			cubeMap.image,
			VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
			static_cast<uint32_t>(bufferCopyRegions.size()),
			bufferCopyRegions.data()
			);

		// Change texture image layout to shader read after all faces have been copied
		cubeMap.imageLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
		vks::tools::setImageLayout(
			copyCmd,
			cubeMap.image,
			VK_IMAGE_ASPECT_COLOR_BIT,
			VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
			cubeMap.imageLayout,
			subresourceRange);

		VulkanExampleBase::flushCommandBuffer(copyCmd, queue, true);

		// Create sampler
		VkSamplerCreateInfo sampler = vks::initializers::samplerCreateInfo();
		sampler.magFilter = VK_FILTER_LINEAR;
		sampler.minFilter = VK_FILTER_LINEAR;
		sampler.mipmapMode = VK_SAMPLER_MIPMAP_MODE_LINEAR;
		sampler.addressModeU = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
		sampler.addressModeV = sampler.addressModeU;
		sampler.addressModeW = sampler.addressModeU;
		sampler.mipLodBias = 0.0f;
		sampler.compareOp = VK_COMPARE_OP_NEVER;
		sampler.minLod = 0.0f;
		sampler.maxLod = cubeMap.mipLevels;
		sampler.borderColor = VK_BORDER_COLOR_FLOAT_OPAQUE_WHITE;
		sampler.maxAnisotropy = 1.0f;
		if (vulkanDevice->features.samplerAnisotropy)
		{
			sampler.maxAnisotropy = vulkanDevice->properties.limits.maxSamplerAnisotropy;
			sampler.anisotropyEnable = VK_TRUE;
		}
		VK_CHECK_RESULT(vkCreateSampler(device, &sampler, nullptr, &cubeMap.sampler));

		// Create image view
		VkImageViewCreateInfo view = vks::initializers::imageViewCreateInfo();
		// Cube map view type
		view.viewType = VK_IMAGE_VIEW_TYPE_CUBE;
		view.format = format;
		view.components = { VK_COMPONENT_SWIZZLE_R, VK_COMPONENT_SWIZZLE_G, VK_COMPONENT_SWIZZLE_B, VK_COMPONENT_SWIZZLE_A };
		view.subresourceRange = { VK_IMAGE_ASPECT_COLOR_BIT, 0, 1, 0, 1 };
		// 6 array layers (faces)
		view.subresourceRange.layerCount = 6;
		// Set number of mip levels
		view.subresourceRange.levelCount = cubeMap.mipLevels;
		view.image = cubeMap.image;
		VK_CHECK_RESULT(vkCreateImageView(device, &view, nullptr, &cubeMap.view));

		// Clean up staging resources
		vkFreeMemory(device, stagingMemory, nullptr);
		vkDestroyBuffer(device, stagingBuffer, nullptr);
	}

	void reBuildCommandBuffers()
	{
		if (!checkCommandBuffers())
		{
			destroyCommandBuffers();
			createCommandBuffers();
		}
		buildCommandBuffers();
	}

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

		VkClearValue clearValues[2];
		clearValues[0].color = defaultClearColor;
		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;

		for (int32_t i = 0; i < drawCmdBuffers.size(); ++i)
		{
			// Set target frame buffer
			renderPassBeginInfo.framebuffer = frameBuffers[i];

			VK_CHECK_RESULT(vkBeginCommandBuffer(drawCmdBuffers[i], &cmdBufInfo));

			vkCmdBeginRenderPass(drawCmdBuffers[i], &renderPassBeginInfo, VK_SUBPASS_CONTENTS_INLINE);

			VkViewport viewport = vks::initializers::viewport((float)width,	(float)height, 0.0f, 1.0f);
			vkCmdSetViewport(drawCmdBuffers[i], 0, 1, &viewport);

			VkRect2D scissor = vks::initializers::rect2D(width,	height,	0, 0);
			vkCmdSetScissor(drawCmdBuffers[i], 0, 1, &scissor);

			VkDeviceSize offsets[1] = { 0 };

			// Skybox
			if (displaySkybox)
			{
				vkCmdBindDescriptorSets(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayout, 0, 1, &descriptorSets.skybox, 0, NULL);
				vkCmdBindVertexBuffers(drawCmdBuffers[i], VERTEX_BUFFER_BIND_ID, 1, &models.skybox.vertices.buffer, offsets);
				vkCmdBindIndexBuffer(drawCmdBuffers[i], models.skybox.indices.buffer, 0, VK_INDEX_TYPE_UINT32);
				vkCmdBindPipeline(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, pipelines.skybox);
				vkCmdDrawIndexed(drawCmdBuffers[i], models.skybox.indexCount, 1, 0, 0, 0);
			}

			// 3D object
			vkCmdBindDescriptorSets(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayout, 0, 1, &descriptorSets.object, 0, NULL);
			vkCmdBindVertexBuffers(drawCmdBuffers[i], VERTEX_BUFFER_BIND_ID, 1, &models.objects[models.objectIndex].vertices.buffer, offsets);
			vkCmdBindIndexBuffer(drawCmdBuffers[i], models.objects[models.objectIndex].indices.buffer, 0, VK_INDEX_TYPE_UINT32);
			vkCmdBindPipeline(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, pipelines.reflect);
			vkCmdDrawIndexed(drawCmdBuffers[i], models.objects[models.objectIndex].indexCount, 1, 0, 0, 0);

			vkCmdEndRenderPass(drawCmdBuffers[i]);

			VK_CHECK_RESULT(vkEndCommandBuffer(drawCmdBuffers[i]));
		}
	}

	void loadMeshes()
	{
		// Skybox
		models.skybox.loadFromFile(getAssetPath() + "models/cube.obj", vertexLayout, 0.05f, vulkanDevice, queue);
		// Objects
		std::vector<std::string> filenames = { "sphere.obj", "teapot.dae", "torusknot.obj" };
		for (auto file : filenames) {
			vks::Model model;
			model.loadFromFile(getAssetPath() + "models/" + file, vertexLayout, 0.05f, vulkanDevice, queue);
			models.objects.push_back(model);
		}
	}

	void setupVertexDescriptions()
	{
		// Binding description
		vertices.bindingDescriptions.resize(1);
		vertices.bindingDescriptions[0] =
			vks::initializers::vertexInputBindingDescription(
				VERTEX_BUFFER_BIND_ID,
				vertexLayout.stride(),
				VK_VERTEX_INPUT_RATE_VERTEX);

		// Attribute descriptions
		// Describes memory layout and shader positions
		vertices.attributeDescriptions.resize(3);
		// Location 0 : Position
		vertices.attributeDescriptions[0] =
			vks::initializers::vertexInputAttributeDescription(
				VERTEX_BUFFER_BIND_ID,
				0,
				VK_FORMAT_R32G32B32_SFLOAT,
				0);
		// Location 1 : Normal
		vertices.attributeDescriptions[1] =
			vks::initializers::vertexInputAttributeDescription(
				VERTEX_BUFFER_BIND_ID,
				1,
				VK_FORMAT_R32G32B32_SFLOAT,
				sizeof(float) * 3);
		// Location 2 : Texture coordinates
		vertices.attributeDescriptions[2] =
			vks::initializers::vertexInputAttributeDescription(
				VERTEX_BUFFER_BIND_ID,
				2,
				VK_FORMAT_R32G32_SFLOAT,
				sizeof(float) * 5);

		vertices.inputState = vks::initializers::pipelineVertexInputStateCreateInfo();
		vertices.inputState.vertexBindingDescriptionCount = vertices.bindingDescriptions.size();
		vertices.inputState.pVertexBindingDescriptions = vertices.bindingDescriptions.data();
		vertices.inputState.vertexAttributeDescriptionCount = vertices.attributeDescriptions.size();
		vertices.inputState.pVertexAttributeDescriptions = vertices.attributeDescriptions.data();
	}

	void setupDescriptorPool()
	{
		std::vector<VkDescriptorPoolSize> poolSizes =
		{
			vks::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, 2),
			vks::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 2)
		};

		VkDescriptorPoolCreateInfo descriptorPoolInfo = 
			vks::initializers::descriptorPoolCreateInfo(
				poolSizes.size(),
				poolSizes.data(),
				2);

		VK_CHECK_RESULT(vkCreateDescriptorPool(device, &descriptorPoolInfo, nullptr, &descriptorPool));
	}

	void setupDescriptorSetLayout()
	{
		std::vector<VkDescriptorSetLayoutBinding> setLayoutBindings = 
		{
			// Binding 0 : Vertex shader uniform buffer
			vks::initializers::descriptorSetLayoutBinding(
				VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, 
				VK_SHADER_STAGE_VERTEX_BIT, 
				0),
			// Binding 1 : Fragment shader image sampler
			vks::initializers::descriptorSetLayoutBinding(
				VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 
				VK_SHADER_STAGE_FRAGMENT_BIT, 
				1)
		};

		VkDescriptorSetLayoutCreateInfo descriptorLayout = 
			vks::initializers::descriptorSetLayoutCreateInfo(
				setLayoutBindings.data(),
				setLayoutBindings.size());

		VK_CHECK_RESULT(vkCreateDescriptorSetLayout(device, &descriptorLayout, nullptr, &descriptorSetLayout));

		VkPipelineLayoutCreateInfo pPipelineLayoutCreateInfo =
			vks::initializers::pipelineLayoutCreateInfo(
				&descriptorSetLayout,
				1);

		VK_CHECK_RESULT(vkCreatePipelineLayout(device, &pPipelineLayoutCreateInfo, nullptr, &pipelineLayout));
	}

	void setupDescriptorSets()
	{
		// Image descriptor for the cube map texture
		VkDescriptorImageInfo textureDescriptor =
			vks::initializers::descriptorImageInfo(
				cubeMap.sampler,
				cubeMap.view,
				cubeMap.imageLayout);

		VkDescriptorSetAllocateInfo allocInfo =
			vks::initializers::descriptorSetAllocateInfo(
				descriptorPool,
				&descriptorSetLayout,
				1);

		// 3D object descriptor set
		VK_CHECK_RESULT(vkAllocateDescriptorSets(device, &allocInfo, &descriptorSets.object));

		std::vector<VkWriteDescriptorSet> writeDescriptorSets =
		{
			// Binding 0 : Vertex shader uniform buffer
			vks::initializers::writeDescriptorSet(
				descriptorSets.object, 
				VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, 
				0, 
				&uniformBuffers.object.descriptor),
			// Binding 1 : Fragment shader cubemap sampler
			vks::initializers::writeDescriptorSet(
				descriptorSets.object, 
				VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 
				1, 
				&textureDescriptor)
		};
		vkUpdateDescriptorSets(device, writeDescriptorSets.size(), writeDescriptorSets.data(), 0, NULL);

		// Sky box descriptor set
		VK_CHECK_RESULT(vkAllocateDescriptorSets(device, &allocInfo, &descriptorSets.skybox));

		writeDescriptorSets =
		{
			// Binding 0 : Vertex shader uniform buffer
			vks::initializers::writeDescriptorSet(
				descriptorSets.skybox,
				VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER,
				0,
				&uniformBuffers.skybox.descriptor),
			// Binding 1 : Fragment shader cubemap sampler
			vks::initializers::writeDescriptorSet(
				descriptorSets.skybox,
				VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER,
				1,
				&textureDescriptor)
		};
		vkUpdateDescriptorSets(device, writeDescriptorSets.size(), writeDescriptorSets.data(), 0, NULL);
	}

	void preparePipelines()
	{
		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_BACK_BIT,
				VK_FRONT_FACE_COUNTER_CLOCKWISE,
				0);

		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, 0);

		VkPipelineMultisampleStateCreateInfo multisampleState =
			vks::initializers::pipelineMultisampleStateCreateInfo(
				VK_SAMPLE_COUNT_1_BIT,
				0);

		std::vector<VkDynamicState> dynamicStateEnables = {
			VK_DYNAMIC_STATE_VIEWPORT,
			VK_DYNAMIC_STATE_SCISSOR
		};
		VkPipelineDynamicStateCreateInfo dynamicState =
			vks::initializers::pipelineDynamicStateCreateInfo(
				dynamicStateEnables.data(),
				dynamicStateEnables.size(),
				0);

		// Skybox pipeline (background cube)
		std::array<VkPipelineShaderStageCreateInfo,2> shaderStages;

		shaderStages[0] = loadShader(getAssetPath() + "shaders/cubemap/skybox.vert.spv", VK_SHADER_STAGE_VERTEX_BIT);
		shaderStages[1] = loadShader(getAssetPath() + "shaders/cubemap/skybox.frag.spv", VK_SHADER_STAGE_FRAGMENT_BIT);

		VkGraphicsPipelineCreateInfo pipelineCreateInfo =
			vks::initializers::pipelineCreateInfo(
				pipelineLayout,
				renderPass,
				0);

		pipelineCreateInfo.pVertexInputState = &vertices.inputState;
		pipelineCreateInfo.pInputAssemblyState = &inputAssemblyState;
		pipelineCreateInfo.pRasterizationState = &rasterizationState;
		pipelineCreateInfo.pColorBlendState = &colorBlendState;
		pipelineCreateInfo.pMultisampleState = &multisampleState;
		pipelineCreateInfo.pViewportState = &viewportState;
		pipelineCreateInfo.pDepthStencilState = &depthStencilState;
		pipelineCreateInfo.pDynamicState = &dynamicState;
		pipelineCreateInfo.stageCount = shaderStages.size();
		pipelineCreateInfo.pStages = shaderStages.data();

		VK_CHECK_RESULT(vkCreateGraphicsPipelines(device, pipelineCache, 1, &pipelineCreateInfo, nullptr, &pipelines.skybox));

		// Cube map reflect pipeline
		shaderStages[0] = loadShader(getAssetPath() + "shaders/cubemap/reflect.vert.spv", VK_SHADER_STAGE_VERTEX_BIT);
		shaderStages[1] = loadShader(getAssetPath() + "shaders/cubemap/reflect.frag.spv", VK_SHADER_STAGE_FRAGMENT_BIT);
		// Enable depth test and write
		depthStencilState.depthWriteEnable = VK_TRUE;
		depthStencilState.depthTestEnable = VK_TRUE;
		// Flip cull mode
		rasterizationState.cullMode = VK_CULL_MODE_FRONT_BIT;
		VK_CHECK_RESULT(vkCreateGraphicsPipelines(device, pipelineCache, 1, &pipelineCreateInfo, nullptr, &pipelines.reflect));
	}

	// Prepare and initialize uniform buffer containing shader uniforms
	void prepareUniformBuffers()
	{
		// Objact vertex shader uniform buffer
		VK_CHECK_RESULT(vulkanDevice->createBuffer(
			VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT,
			VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT,
			&uniformBuffers.object,
			sizeof(uboVS)));

		// Skybox vertex shader uniform buffer
		VK_CHECK_RESULT(vulkanDevice->createBuffer(
			VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT,
			VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT,
			&uniformBuffers.skybox,
			sizeof(uboVS)));

		// Map persistent
		VK_CHECK_RESULT(uniformBuffers.object.map());
		VK_CHECK_RESULT(uniformBuffers.skybox.map());

		updateUniformBuffers();
	}

	void updateUniformBuffers()
	{
		// 3D object
		glm::mat4 viewMatrix = glm::mat4();
		uboVS.projection = glm::perspective(glm::radians(60.0f), (float)width / (float)height, 0.001f, 256.0f);
		viewMatrix = glm::translate(viewMatrix, glm::vec3(0.0f, 0.0f, zoom));

		uboVS.model = glm::mat4();
		uboVS.model = viewMatrix * glm::translate(uboVS.model, cameraPos);
		uboVS.model = glm::rotate(uboVS.model, glm::radians(rotation.x), glm::vec3(1.0f, 0.0f, 0.0f));
		uboVS.model = glm::rotate(uboVS.model, glm::radians(rotation.y), glm::vec3(0.0f, 1.0f, 0.0f));
		uboVS.model = glm::rotate(uboVS.model, glm::radians(rotation.z), glm::vec3(0.0f, 0.0f, 1.0f));

		memcpy(uniformBuffers.object.mapped, &uboVS, sizeof(uboVS));

		// Skybox
		viewMatrix = glm::mat4();
		uboVS.projection = glm::perspective(glm::radians(60.0f), (float)width / (float)height, 0.001f, 256.0f);

		uboVS.model = glm::mat4();
		uboVS.model = viewMatrix * glm::translate(uboVS.model, glm::vec3(0, 0, 0));
		uboVS.model = glm::rotate(uboVS.model, glm::radians(rotation.x), glm::vec3(1.0f, 0.0f, 0.0f));
		uboVS.model = glm::rotate(uboVS.model, glm::radians(rotation.y), glm::vec3(0.0f, 1.0f, 0.0f));
		uboVS.model = glm::rotate(uboVS.model, glm::radians(rotation.z), glm::vec3(0.0f, 0.0f, 1.0f));

		memcpy(uniformBuffers.skybox.mapped, &uboVS, sizeof(uboVS));
	}

	void draw()
	{
		VulkanExampleBase::prepareFrame();

		submitInfo.commandBufferCount = 1;
		submitInfo.pCommandBuffers = &drawCmdBuffers[currentBuffer];
		VK_CHECK_RESULT(vkQueueSubmit(queue, 1, &submitInfo, VK_NULL_HANDLE));

		VulkanExampleBase::submitFrame();
	}

	void prepare()
	{
		VulkanExampleBase::prepare();
		loadMeshes();
		setupVertexDescriptions();
		prepareUniformBuffers();
		loadCubemap(
			getAssetPath() + "textures/cubemap_yokohama.ktx",
			VK_FORMAT_BC3_UNORM_BLOCK,
			false);
		setupDescriptorSetLayout();
		preparePipelines();
		setupDescriptorPool();
		setupDescriptorSets();
		buildCommandBuffers();
		prepared = true;
	}

	virtual void render()
	{
		if (!prepared)
			return;
		draw();
	}

	virtual void viewChanged()
	{
		updateUniformBuffers();
	}

	void toggleSkyBox()
	{
		displaySkybox = !displaySkybox;
		reBuildCommandBuffers();
	}

	void toggleObject()
	{
		models.objectIndex++;
		if (models.objectIndex >= static_cast<uint32_t>(models.objects.size()))
		{
			models.objectIndex = 0;
		}
		reBuildCommandBuffers();
	}

	void changeLodBias(float delta)
	{
		uboVS.lodBias += delta;
		if (uboVS.lodBias < 0.0f)
		{
			uboVS.lodBias = 0.0f;
		}
		if (uboVS.lodBias > cubeMap.mipLevels)
		{
			uboVS.lodBias = cubeMap.mipLevels;
		}
		updateUniformBuffers();
		updateTextOverlay();
	}

	virtual void keyPressed(uint32_t keyCode)
	{
		switch (keyCode)
		{
		case KEY_S:
		case GAMEPAD_BUTTON_A:
			toggleSkyBox();
			break;
		case KEY_SPACE:
		case GAMEPAD_BUTTON_X:
			toggleObject();
			break;
		case KEY_KPADD:
		case GAMEPAD_BUTTON_R1:
			changeLodBias(0.1f);
			break;
		case KEY_KPSUB:
		case GAMEPAD_BUTTON_L1:
			changeLodBias(-0.1f);
			break;
		}
	}

	virtual void getOverlayText(VulkanTextOverlay *textOverlay)
	{
		std::stringstream ss;
		ss << std::setprecision(2) << std::fixed << uboVS.lodBias;
#if defined(__ANDROID__)
		textOverlay->addText("Press \"Button A\" to toggle skybox", 5.0f, 85.0f, VulkanTextOverlay::alignLeft);
		textOverlay->addText("Press \"Button X\" to toggle object", 5.0f, 100.0f, VulkanTextOverlay::alignLeft);
		textOverlay->addText("LOD bias: " + ss.str() + " (Buttons L1/R1 to change)", 5.0f, 115.0f, VulkanTextOverlay::alignLeft);
#else
		textOverlay->addText("Press \"s\" to toggle skybox", 5.0f, 85.0f, VulkanTextOverlay::alignLeft);
		textOverlay->addText("Press \"space\" to toggle object", 5.0f, 100.0f, VulkanTextOverlay::alignLeft);
		textOverlay->addText("LOD bias: " + ss.str() + " (numpad +/- to change)", 5.0f, 115.0f, VulkanTextOverlay::alignLeft);
#endif
	}
};

VULKAN_EXAMPLE_MAIN()