/*
* Vulkan Example - Texture loading (and display) example (including mip maps)
*
* 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 <vulkan/vulkan.h>
#include "vulkanexamplebase.h"

#define VERTEX_BUFFER_BIND_ID 0
#define ENABLE_VALIDATION false

// Vertex layout for this example
struct Vertex {
	float pos[3];
	float uv[2];
};

class VulkanExample : public VulkanExampleBase
{
public:
	// Contains all Vulkan objects that are required to store and use a texture
	// Note that this repository contains a texture loader (vulkantextureloader.h)
	// that encapsulates texture loading functionality in a class that is used
	// in subsequent demos
	struct Texture {
		VkSampler sampler;
		VkImage image;
		VkImageLayout imageLayout;
		VkDeviceMemory deviceMemory;
		VkImageView view;
		uint32_t width, height;
		uint32_t mipLevels;
	} texture;

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

	struct {
		int count;
		VkBuffer buf;
		VkDeviceMemory mem;
	} indices;

	vkTools::UniformData uniformDataVS;

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

	struct {
		VkPipeline solid;
	} pipelines;

	VkPipelineLayout pipelineLayout;
	VkDescriptorSet descriptorSet;
	VkDescriptorSetLayout descriptorSetLayout;

	VulkanExample() : VulkanExampleBase(ENABLE_VALIDATION)
	{
		zoom = -2.5f;
		rotation = { 45.0f, 0.0f, 0.0f };
		title = "Vulkan Example - Texturing";
	}

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

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

		vkDestroyPipeline(device, pipelines.solid, nullptr);

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

		vkDestroyBuffer(device, vertices.buf, nullptr);
		vkFreeMemory(device, vertices.mem, nullptr);

		vkDestroyBuffer(device, indices.buf, nullptr);
		vkFreeMemory(device, indices.mem, nullptr);

		vkDestroyBuffer(device, uniformDataVS.buffer, nullptr);
		vkFreeMemory(device, uniformDataVS.memory, nullptr);
	}

	// Create an image memory barrier for changing the layout of
	// an image and put it into an active command buffer
	void setImageLayout(VkImage image, VkImageAspectFlags aspectMask, VkImageLayout oldImageLayout, VkImageLayout newImageLayout, uint32_t mipLevel, uint32_t mipLevelCount)
	{
		// Create an image barrier object
		VkImageMemoryBarrier imageMemoryBarrier = vkTools::initializers::imageMemoryBarrier();;
		imageMemoryBarrier.oldLayout = oldImageLayout;
		imageMemoryBarrier.newLayout = newImageLayout;
		imageMemoryBarrier.image = image;
		imageMemoryBarrier.subresourceRange.aspectMask = aspectMask;
		imageMemoryBarrier.subresourceRange.baseMipLevel = mipLevel;
		imageMemoryBarrier.subresourceRange.levelCount = mipLevelCount;
		imageMemoryBarrier.subresourceRange.layerCount = 1;

		// Only sets masks for layouts used in this example
		// For a more complete version that can be used with
		// other layouts see vkTools::setImageLayout

		// Source layouts (new)

		if (oldImageLayout == VK_IMAGE_LAYOUT_PREINITIALIZED)
		{
			imageMemoryBarrier.srcAccessMask = VK_ACCESS_HOST_WRITE_BIT | VK_ACCESS_TRANSFER_WRITE_BIT;
		}

		// Target layouts (new)

		// New layout is transfer destination (copy, blit)
		// Make sure any reads from and writes to the image have been finished
		if (newImageLayout == VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL)
		{
			imageMemoryBarrier.dstAccessMask = VK_ACCESS_TRANSFER_READ_BIT | VK_ACCESS_HOST_WRITE_BIT | VK_ACCESS_TRANSFER_WRITE_BIT;
		}

		// New layout is shader read (sampler, input attachment)
		// Make sure any writes to the image have been finished
		if (newImageLayout == VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL)
		{
			imageMemoryBarrier.srcAccessMask = VK_ACCESS_HOST_WRITE_BIT | VK_ACCESS_TRANSFER_WRITE_BIT;
			imageMemoryBarrier.dstAccessMask = VK_ACCESS_SHADER_READ_BIT;
		}

		// New layout is transfer source (copy, blit)
		// Make sure any reads from and writes to the image have been finished
		if (newImageLayout == VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL)
		{
			imageMemoryBarrier.dstAccessMask = VK_ACCESS_TRANSFER_READ_BIT | VK_ACCESS_HOST_WRITE_BIT | VK_ACCESS_TRANSFER_WRITE_BIT;
		}

		// Put barrier on top
		VkPipelineStageFlags srcStageFlags = VK_PIPELINE_STAGE_TOP_OF_PIPE_BIT;
		VkPipelineStageFlags destStageFlags = VK_PIPELINE_STAGE_TOP_OF_PIPE_BIT;

		// Put barrier inside setup command buffer
		vkCmdPipelineBarrier(
			setupCmdBuffer, 
			srcStageFlags, 
			destStageFlags, 
			VK_FLAGS_NONE, 
			0, nullptr,
			0, nullptr,
			1, &imageMemoryBarrier);
	}

	void loadTexture(const char* fileName, VkFormat format, bool forceLinearTiling)
	{
		VkFormatProperties formatProperties;
		VkResult err;

		gli::texture2D tex2D(gli::load(fileName));
		assert(!tex2D.empty());

		texture.width = tex2D[0].dimensions().x;
		texture.height = tex2D[0].dimensions().y;
		texture.mipLevels = tex2D.levels();

		// Get device properites for the requested texture format
		vkGetPhysicalDeviceFormatProperties(physicalDevice, format, &formatProperties);

		// Only use linear tiling if requested (and supported by the device)
		// Support for linear tiling is mostly limited, so prefer to use
		// optimal tiling instead
		// On most implementations linear tiling will only support a very
		// limited amount of formats and features (mip maps, cubemaps, arrays, etc.)
		VkBool32 useStaging = true;

		// Only use linear tiling if forced
		if (forceLinearTiling)
		{
			// Don't use linear if format is not supported for (linear) shader sampling
			useStaging = !(formatProperties.linearTilingFeatures & VK_FORMAT_FEATURE_SAMPLED_IMAGE_BIT);
		}

		VkImageCreateInfo imageCreateInfo = vkTools::initializers::imageCreateInfo();
		imageCreateInfo.imageType = VK_IMAGE_TYPE_2D;
		imageCreateInfo.format = format;
		imageCreateInfo.mipLevels = 1;
		imageCreateInfo.arrayLayers = 1;
		imageCreateInfo.samples = VK_SAMPLE_COUNT_1_BIT;
		imageCreateInfo.tiling = VK_IMAGE_TILING_LINEAR;
		imageCreateInfo.usage = (useStaging) ? VK_IMAGE_USAGE_TRANSFER_SRC_BIT : VK_IMAGE_USAGE_SAMPLED_BIT;
		imageCreateInfo.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
		imageCreateInfo.initialLayout = VK_IMAGE_LAYOUT_PREINITIALIZED; 
		imageCreateInfo.flags = 0;
		imageCreateInfo.extent = { texture.width, texture.height, 1 };

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

		if (useStaging)
		{
			// Load all available mip levels into linear textures
			// and copy to optimal tiling target
			struct MipLevel {
				VkImage image;
				VkDeviceMemory memory;
			};
			std::vector<MipLevel> mipLevels;
			mipLevels.resize(texture.mipLevels);

			// Load mip levels into linear textures that are used to copy from
			for (uint32_t level = 0; level < texture.mipLevels; level++)
			{
				imageCreateInfo.extent.width = tex2D[level].dimensions().x;
				imageCreateInfo.extent.height = tex2D[level].dimensions().y;
				imageCreateInfo.extent.depth = 1;

				err = vkCreateImage(device, &imageCreateInfo, nullptr, &mipLevels[level].image);
				assert(!err);

				vkGetImageMemoryRequirements(device, mipLevels[level].image, &memReqs);
				memAllocInfo.allocationSize = memReqs.size;
				getMemoryType(memReqs.memoryTypeBits, VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT, &memAllocInfo.memoryTypeIndex);
				err = vkAllocateMemory(device, &memAllocInfo, nullptr, &mipLevels[level].memory);
				assert(!err);
				err = vkBindImageMemory(device, mipLevels[level].image, mipLevels[level].memory, 0);
				assert(!err);

				VkImageSubresource subRes = {};
				subRes.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;

				VkSubresourceLayout subResLayout;
				void *data;

				vkGetImageSubresourceLayout(device, mipLevels[level].image, &subRes, &subResLayout);
				assert(!err);
				err = vkMapMemory(device, mipLevels[level].memory, 0, memReqs.size, 0, &data);
				assert(!err);
				memcpy(data, tex2D[level].data(), tex2D[level].size());
				vkUnmapMemory(device, mipLevels[level].memory);

				// Image barrier for linear image (base)
				// Linear image will be used as a source for the copy
				setImageLayout(
					mipLevels[level].image,
					VK_IMAGE_ASPECT_COLOR_BIT,
					VK_IMAGE_LAYOUT_PREINITIALIZED,
					VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL,
					0,
					1);
			}

			// Setup texture as blit target with optimal tiling
			imageCreateInfo.tiling = VK_IMAGE_TILING_OPTIMAL;
			imageCreateInfo.usage = VK_IMAGE_USAGE_TRANSFER_DST_BIT | VK_IMAGE_USAGE_SAMPLED_BIT;
			imageCreateInfo.mipLevels = texture.mipLevels;
			imageCreateInfo.extent = { texture.width, texture.height, 1 };

			err = vkCreateImage(device, &imageCreateInfo, nullptr, &texture.image);
			assert(!err);

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

			memAllocInfo.allocationSize = memReqs.size;

			getMemoryType(memReqs.memoryTypeBits, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, &memAllocInfo.memoryTypeIndex);
			err = vkAllocateMemory(device, &memAllocInfo, nullptr, &texture.deviceMemory);
			assert(!err);
			err = vkBindImageMemory(device, texture.image, texture.deviceMemory, 0);
			assert(!err);

			// Image barrier for optimal image (target)
			// Optimal image will be used as destination for the copy

			// Set initial layout for all mip levels of the optimal (target) tiled texture
			setImageLayout(
				texture.image,
				VK_IMAGE_ASPECT_COLOR_BIT,
				VK_IMAGE_LAYOUT_PREINITIALIZED,
				VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
				0,
				texture.mipLevels);

			// Copy mip levels one by one
			for (uint32_t level = 0; level < texture.mipLevels; ++level)
			{
				// Copy region for image blit
				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 = 0;
				// Set mip level to copy the linear image to
				copyRegion.dstSubresource.mipLevel = level;
				copyRegion.dstSubresource.layerCount = 1;
				copyRegion.dstOffset = { 0, 0, 0 };

				copyRegion.extent.width = tex2D[level].dimensions().x;
				copyRegion.extent.height = tex2D[level].dimensions().y;
				copyRegion.extent.depth = 1;

				// Put image copy into command buffer
				vkCmdCopyImage(
					setupCmdBuffer,
					mipLevels[level].image, 
					VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL,
					texture.image, 
					VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
					1, &copyRegion);
			}

			// Change texture image layout to shader read after all mip levels have been copied
			texture.imageLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
			setImageLayout(
				texture.image,
				VK_IMAGE_ASPECT_COLOR_BIT,
				VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
				texture.imageLayout,
				0,
				texture.mipLevels);

			flushSetupCommandBuffer();
			createSetupCommandBuffer();

			// Clean up linear images 
			// No longer required after mip levels
			// have been transformed over to optimal tiling
			for (auto& level : mipLevels)
			{
				vkDestroyImage(device, level.image, nullptr);
				vkFreeMemory(device, level.memory, nullptr);
			}
		}
		else
		{
			// Prefer using optimal tiling, as linear tiling 
			// may support only a small set of features 
			// depending on implementation (e.g. no mip maps, only one layer, etc.)

			VkImage mappableImage;
			VkDeviceMemory mappableMemory;

			// Load mip map level 0 to linear tiling image
			err = vkCreateImage(device, &imageCreateInfo, nullptr, &mappableImage);
			assert(!err);

			// Get memory requirements for this image 
			// like size and alignment
			vkGetImageMemoryRequirements(device, mappableImage, &memReqs);
			// Set memory allocation size to required memory size
			memAllocInfo.allocationSize = memReqs.size;

			// Get memory type that can be mapped to host memory
			getMemoryType(memReqs.memoryTypeBits, VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT, &memAllocInfo.memoryTypeIndex);

			// Allocate host memory
			err = vkAllocateMemory(device, &memAllocInfo, nullptr, &mappableMemory);
			assert(!err);

			// Bind allocated image for use
			err = vkBindImageMemory(device, mappableImage, mappableMemory, 0);
			assert(!err);

			// Get sub resource layout
			// Mip map count, array layer, etc.
			VkImageSubresource subRes = {};
			subRes.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;

			VkSubresourceLayout subResLayout;
			void *data;

			// Get sub resources layout 
			// Includes row pitch, size offsets, etc.
			vkGetImageSubresourceLayout(device, mappableImage, &subRes, &subResLayout);
			assert(!err);

			// Map image memory
			err = vkMapMemory(device, mappableMemory, 0, memReqs.size, 0, &data);
			assert(!err);

			// Copy image data into memory
			memcpy(data, tex2D[subRes.mipLevel].data(), tex2D[subRes.mipLevel].size());

			vkUnmapMemory(device, mappableMemory);

			// Linear tiled images don't need to be staged
			// and can be directly used as textures
			texture.image = mappableImage;
			texture.deviceMemory = mappableMemory;
			texture.imageLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
			
			// Setup image memory barrier
			setImageLayout(
				texture.image, 
				VK_IMAGE_ASPECT_COLOR_BIT, 
				VK_IMAGE_LAYOUT_UNDEFINED, 
				texture.imageLayout,
				0,
				1);
		}

		// Create sampler
		// In Vulkan textures are accessed by samplers
		// This separates all the sampling information from the 
		// texture data
		// This means you could have multiple sampler objects
		// for the same texture with different settings
		// Similar to the samplers available with OpenGL 3.3
		VkSamplerCreateInfo sampler = vkTools::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_REPEAT;
		sampler.addressModeV = VK_SAMPLER_ADDRESS_MODE_REPEAT;
		sampler.addressModeW = VK_SAMPLER_ADDRESS_MODE_REPEAT;
		sampler.mipLodBias = 0.0f;
		sampler.compareOp = VK_COMPARE_OP_NEVER;
		sampler.minLod = 0.0f;
		// Max level-of-detail should match mip level count
		sampler.maxLod = (useStaging) ? (float)texture.mipLevels : 0.0f;
		// Enable anisotropic filtering
		sampler.maxAnisotropy = 8;
		sampler.anisotropyEnable = VK_TRUE;
		sampler.borderColor = VK_BORDER_COLOR_FLOAT_OPAQUE_WHITE;
		err = vkCreateSampler(device, &sampler, nullptr, &texture.sampler);
		assert(!err);

		// Create image view
		// Textures are not directly accessed by the shaders and
		// are abstracted by image views containing additional
		// information and sub resource ranges
		VkImageViewCreateInfo view = vkTools::initializers::imageViewCreateInfo();
		view.image = VK_NULL_HANDLE;
		view.viewType = VK_IMAGE_VIEW_TYPE_2D;
		view.format = format;
		view.components = { VK_COMPONENT_SWIZZLE_R, VK_COMPONENT_SWIZZLE_G, VK_COMPONENT_SWIZZLE_B, VK_COMPONENT_SWIZZLE_A };
		view.subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
		view.subresourceRange.baseMipLevel = 0;
		view.subresourceRange.baseArrayLayer = 0;
		view.subresourceRange.layerCount = 1;
		// Linear tiling usually won't support mip maps
		// Only set mip map count if optimal tiling is used
		view.subresourceRange.levelCount = (useStaging) ? texture.mipLevels : 1;
		view.image = texture.image;
		err = vkCreateImageView(device, &view, nullptr, &texture.view);
		assert(!err);
	}

	// Free staging resources used while creating a texture
	void destroyTextureImage(Texture texture)
	{
		vkDestroyImage(device, texture.image, nullptr);
		vkFreeMemory(device, texture.deviceMemory, nullptr);
	}

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

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

		VkRenderPassBeginInfo renderPassBeginInfo = vkTools::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;

		VkResult err;

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

			err = vkBeginCommandBuffer(drawCmdBuffers[i], &cmdBufInfo);
			assert(!err);

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

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

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

			vkCmdBindDescriptorSets(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayout, 0, 1, &descriptorSet, 0, NULL);
			vkCmdBindPipeline(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, pipelines.solid);

			VkDeviceSize offsets[1] = { 0 };
			vkCmdBindVertexBuffers(drawCmdBuffers[i], VERTEX_BUFFER_BIND_ID, 1, &vertices.buf, offsets);
			vkCmdBindIndexBuffer(drawCmdBuffers[i], indices.buf, 0, VK_INDEX_TYPE_UINT32);

			vkCmdDrawIndexed(drawCmdBuffers[i], indices.count, 1, 0, 0, 0);

			vkCmdEndRenderPass(drawCmdBuffers[i]);

			err = vkEndCommandBuffer(drawCmdBuffers[i]);
			assert(!err);
		}
	}

	void draw()
	{
		VkResult err;

		// Get next image in the swap chain (back/front buffer)
		err = swapChain.acquireNextImage(semaphores.presentComplete, &currentBuffer);
		assert(!err);

		submitPostPresentBarrier(swapChain.buffers[currentBuffer].image);

		// Command buffer to be sumitted to the queue
		submitInfo.commandBufferCount = 1;
		submitInfo.pCommandBuffers = &drawCmdBuffers[currentBuffer];

		// Submit to queue
		err = vkQueueSubmit(queue, 1, &submitInfo, VK_NULL_HANDLE);
		assert(!err);

		submitPrePresentBarrier(swapChain.buffers[currentBuffer].image);

		err = swapChain.queuePresent(queue, currentBuffer, semaphores.renderComplete);
		assert(!err);

		err = vkQueueWaitIdle(queue);
		assert(!err);
	}

	void generateQuad()
	{
		// Setup vertices for a single uv-mapped quad
#define dim 1.0f
		std::vector<Vertex> vertexBuffer =
		{
			{ { dim,  dim, 0.0f },{ 1.0f, 1.0f } },
			{ { -dim,  dim, 0.0f },{ 0.0f, 1.0f } },
			{ { -dim, -dim, 0.0f },{ 0.0f, 0.0f } },
			{ { dim, -dim, 0.0f },{ 1.0f, 0.0f } }
		};
#undef dim
		createBuffer(
			VK_BUFFER_USAGE_VERTEX_BUFFER_BIT,
			vertexBuffer.size() * sizeof(Vertex),
			vertexBuffer.data(),
			&vertices.buf,
			&vertices.mem);

		// Setup indices
		std::vector<uint32_t> indexBuffer = { 0,1,2, 2,3,0 };
		indices.count = indexBuffer.size();

		createBuffer(
			VK_BUFFER_USAGE_INDEX_BUFFER_BIT,
			indexBuffer.size() * sizeof(uint32_t),
			indexBuffer.data(),
			&indices.buf,
			&indices.mem);
	}

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

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

		vertices.inputState = vkTools::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()
	{
		// Example uses one ubo and one image sampler
		std::vector<VkDescriptorPoolSize> poolSizes =
		{
			vkTools::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, 1),
			vkTools::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 1)
		};

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

		VkResult vkRes = vkCreateDescriptorPool(device, &descriptorPoolInfo, nullptr, &descriptorPool);
		assert(!vkRes);
	}

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

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

		VkResult err = vkCreateDescriptorSetLayout(device, &descriptorLayout, nullptr, &descriptorSetLayout);
		assert(!err);

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

		err = vkCreatePipelineLayout(device, &pPipelineLayoutCreateInfo, nullptr, &pipelineLayout);
		assert(!err);
	}

	void setupDescriptorSet()
	{
		VkDescriptorSetAllocateInfo allocInfo = 
			vkTools::initializers::descriptorSetAllocateInfo(
				descriptorPool,
				&descriptorSetLayout,
				1);

		VkResult vkRes = vkAllocateDescriptorSets(device, &allocInfo, &descriptorSet);
		assert(!vkRes);

		// Image descriptor for the color map texture
		VkDescriptorImageInfo texDescriptor =
			vkTools::initializers::descriptorImageInfo(
				texture.sampler,
				texture.view,
				VK_IMAGE_LAYOUT_GENERAL);

		std::vector<VkWriteDescriptorSet> writeDescriptorSets =
		{
			// Binding 0 : Vertex shader uniform buffer
			vkTools::initializers::writeDescriptorSet(
				descriptorSet, 
				VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, 
				0, 
				&uniformDataVS.descriptor),
			// Binding 1 : Fragment shader texture sampler
			vkTools::initializers::writeDescriptorSet(
				descriptorSet, 
				VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 
				1, 
				&texDescriptor)
		};

		vkUpdateDescriptorSets(device, writeDescriptorSets.size(), writeDescriptorSets.data(), 0, NULL);
	}

	void preparePipelines()
	{
		VkPipelineInputAssemblyStateCreateInfo inputAssemblyState =
			vkTools::initializers::pipelineInputAssemblyStateCreateInfo(
				VK_PRIMITIVE_TOPOLOGY_TRIANGLE_LIST,
				0,
				VK_FALSE);

		VkPipelineRasterizationStateCreateInfo rasterizationState =
			vkTools::initializers::pipelineRasterizationStateCreateInfo(
				VK_POLYGON_MODE_FILL,
				VK_CULL_MODE_NONE,
				VK_FRONT_FACE_COUNTER_CLOCKWISE,
				0);

		VkPipelineColorBlendAttachmentState blendAttachmentState =
			vkTools::initializers::pipelineColorBlendAttachmentState(
				0xf,
				VK_FALSE);

		VkPipelineColorBlendStateCreateInfo colorBlendState =
			vkTools::initializers::pipelineColorBlendStateCreateInfo(
				1, 
				&blendAttachmentState);

		VkPipelineDepthStencilStateCreateInfo depthStencilState =
			vkTools::initializers::pipelineDepthStencilStateCreateInfo(
				VK_TRUE,
				VK_TRUE,
				VK_COMPARE_OP_LESS_OR_EQUAL);

		VkPipelineViewportStateCreateInfo viewportState =
			vkTools::initializers::pipelineViewportStateCreateInfo(1, 1, 0);

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

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

		// Load shaders
		std::array<VkPipelineShaderStageCreateInfo,2> shaderStages;

		shaderStages[0] = loadShader("./../data/shaders/texture.vert.spv", VK_SHADER_STAGE_VERTEX_BIT);
		shaderStages[1] = loadShader("./../data/shaders/texture.frag.spv", VK_SHADER_STAGE_FRAGMENT_BIT);

		VkGraphicsPipelineCreateInfo pipelineCreateInfo =
			vkTools::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();

		VkResult err = vkCreateGraphicsPipelines(device, pipelineCache, 1, &pipelineCreateInfo, nullptr, &pipelines.solid);
		assert(!err);
	}

	// Prepare and initialize uniform buffer containing shader uniforms
	void prepareUniformBuffers()
	{
		// Vertex shader uniform buffer block
		createBuffer(
			VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT,
			sizeof(uboVS),
			&uboVS,
			&uniformDataVS.buffer,
			&uniformDataVS.memory,
			&uniformDataVS.descriptor);

		updateUniformBuffers();
	}

	void updateUniformBuffers()
	{
		// Vertex shader
		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, 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));

		uint8_t *pData;
		VkResult err = vkMapMemory(device, uniformDataVS.memory, 0, sizeof(uboVS), 0, (void **)&pData);
		assert(!err);
		memcpy(pData, &uboVS, sizeof(uboVS));
		vkUnmapMemory(device, uniformDataVS.memory);
	}

	void prepare()
	{
		VulkanExampleBase::prepare();
		generateQuad();
		setupVertexDescriptions();
		prepareUniformBuffers();
		loadTexture(
			"./../data/textures/igor_and_pal_bc3.ktx", 
			VK_FORMAT_BC3_UNORM_BLOCK, 
			false);
		setupDescriptorSetLayout();
		preparePipelines();
		setupDescriptorPool();
		setupDescriptorSet();
		buildCommandBuffers();
		prepared = true;
	}

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

	virtual void viewChanged()
	{
		updateUniformBuffers();
	}

	void changeLodBias(float delta)
	{
		uboVS.lodBias += delta;
		if (uboVS.lodBias < 0.0f)
		{
			uboVS.lodBias = 0.0f;
		}
		if (uboVS.lodBias > 8.0f)
		{
			uboVS.lodBias = 8.0f;
		}
		updateUniformBuffers();
	}
};

VulkanExample *vulkanExample;

#ifdef _WIN32

LRESULT CALLBACK WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
	if (vulkanExample != NULL)
	{
		vulkanExample->handleMessages(hWnd, uMsg, wParam, lParam);
		if (uMsg == WM_KEYDOWN)
		{
			switch (wParam)
			{
			case VK_ADD:
				vulkanExample->changeLodBias(0.1f);
				break;
			case VK_SUBTRACT:
				vulkanExample->changeLodBias(-0.1f);
				break;
			}
		}
	}
	return (DefWindowProc(hWnd, uMsg, wParam, lParam));
}

#else 

static void handleEvent(const xcb_generic_event_t *event)
{
	if (vulkanExample != NULL)
	{
		vulkanExample->handleEvent(event);
	}
}
#endif

#ifdef _WIN32
int APIENTRY WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR pCmdLine, int nCmdShow)
#else
int main(const int argc, const char *argv[])
#endif
{
	vulkanExample = new VulkanExample();
#ifdef _WIN32
	vulkanExample->setupWindow(hInstance, WndProc);
#else
	vulkanExample->setupWindow();
#endif
	vulkanExample->initSwapchain();
	vulkanExample->prepare();
	vulkanExample->renderLoop();
	delete(vulkanExample);
	return 0;
}