stencilbuffer.cpp

/*
* Vulkan Example - Rendering outlines using the stencil buffer
*
* Copyright (C) 2016-2017 by Sascha Willems - www.saschawillems.de
*
* This code is licensed under the MIT license (MIT)
* (http://opensource.org/licenses/MIT)
*/

#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.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 "VulkanBuffer.hpp"
#include "VulkanModel.hpp"
#include "vulkanexamplebase.h"
#include <vulkan/vulkan.h>

#define ENABLE_VALIDATION false

class VulkanExample : public VulkanExampleBase {
public:
  // Vertex layout for the models
  vks::VertexLayout vertexLayout = vks::VertexLayout({
      vks::VERTEX_COMPONENT_POSITION, vks::VERTEX_COMPONENT_COLOR,
      vks::VERTEX_COMPONENT_NORMAL,
  });

  vks::Model model;

  struct UBO {
    glm::mat4 projection;
    glm::mat4 model;
    glm::vec4 lightPos = glm::vec4(0.0f, -2.0f, 1.0f, 0.0f);
    // Vertex shader extrudes model by this value along normals for outlining
    float outlineWidth = 0.05f;
  } uboVS;

  vks::Buffer uniformBufferVS;

  struct {
    VkPipeline stencil;
    VkPipeline outline;
  } pipelines;

  VkPipelineLayout pipelineLayout;
  VkDescriptorSet descriptorSet;
  VkDescriptorSetLayout descriptorSetLayout;

  VulkanExample() : VulkanExampleBase(ENABLE_VALIDATION) {
    title = "Stencil buffer outlines";
    timerSpeed *= 0.25f;
    camera.type = Camera::CameraType::lookat;
    camera.setPerspective(60.0f, (float)width / (float)height, 0.1f, 512.0f);
    camera.setRotation(glm::vec3(2.5f, -35.0f, 0.0f));
    camera.setTranslation(glm::vec3(0.08f, 3.6f, -8.4f));
    settings.overlay = true;
  }

  ~VulkanExample() {
    vkDestroyPipeline(device, pipelines.stencil, nullptr);
    vkDestroyPipeline(device, pipelines.outline, nullptr);

    vkDestroyPipelineLayout(device, pipelineLayout, nullptr);

    vkDestroyDescriptorSetLayout(device, descriptorSetLayout, nullptr);

    model.destroy();
    uniformBufferVS.destroy();
  }

  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) {
      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};

      vkCmdBindVertexBuffers(drawCmdBuffers[i], 0, 1, &model.vertices.buffer,
                             offsets);
      vkCmdBindIndexBuffer(drawCmdBuffers[i], model.indices.buffer, 0,
                           VK_INDEX_TYPE_UINT32);

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

      // First pass renders object (toon shaded) and fills stencil buffer
      vkCmdBindPipeline(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS,
                        pipelines.stencil);
      vkCmdDrawIndexed(drawCmdBuffers[i], model.indexCount, 1, 0, 0, 0);

      // Second pass renders scaled object only where stencil was not set by
      // first pass
      vkCmdBindPipeline(drawCmdBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS,
                        pipelines.outline);
      vkCmdDrawIndexed(drawCmdBuffers[i], model.indexCount, 1, 0, 0, 0);

      vkCmdEndRenderPass(drawCmdBuffers[i]);

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

  void loadAssets() {
    model.loadFromFile(getAssetPath() + "models/venus.fbx", vertexLayout, 0.3f,
                       vulkanDevice, queue);
  }

  void setupDescriptorPool() {
    std::vector<VkDescriptorPoolSize> poolSizes = {
        vks::initializers::descriptorPoolSize(VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER,
                                              1),
    };
    VkDescriptorPoolCreateInfo descriptorPoolInfo =
        vks::initializers::descriptorPoolCreateInfo(
            static_cast<uint32_t>(poolSizes.size()), poolSizes.data(), 1);
    VK_CHECK_RESULT(vkCreateDescriptorPool(device, &descriptorPoolInfo, nullptr,
                                           &descriptorPool));
  }

  void setupDescriptorSetLayout() {
    std::vector<VkDescriptorSetLayoutBinding> setLayoutBindings = {
        vks::initializers::descriptorSetLayoutBinding(
            VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, VK_SHADER_STAGE_VERTEX_BIT, 0)};

    VkDescriptorSetLayoutCreateInfo descriptorLayoutInfo =
        vks::initializers::descriptorSetLayoutCreateInfo(
            setLayoutBindings.data(), 1);
    VK_CHECK_RESULT(vkCreateDescriptorSetLayout(device, &descriptorLayoutInfo,
                                                nullptr, &descriptorSetLayout));

    VkPipelineLayoutCreateInfo pipelineLayoutInfo =
        vks::initializers::pipelineLayoutCreateInfo(&descriptorSetLayout, 1);
    VK_CHECK_RESULT(vkCreatePipelineLayout(device, &pipelineLayoutInfo, nullptr,
                                           &pipelineLayout));
  }

  void setupDescriptorSet() {
    VkDescriptorSetAllocateInfo allocInfo =
        vks::initializers::descriptorSetAllocateInfo(descriptorPool,
                                                     &descriptorSetLayout, 1);
    VK_CHECK_RESULT(
        vkAllocateDescriptorSets(device, &allocInfo, &descriptorSet));
    std::vector<VkWriteDescriptorSet> modelWriteDescriptorSets = {
        vks::initializers::writeDescriptorSet(descriptorSet,
                                              VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER,
                                              0, &uniformBufferVS.descriptor)};
    vkUpdateDescriptorSets(
        device, static_cast<uint32_t>(modelWriteDescriptorSets.size()),
        modelWriteDescriptorSets.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_FRONT_BIT,
            VK_FRONT_FACE_CLOCKWISE, 0);

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

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

    VkPipelineDepthStencilStateCreateInfo depthStencilState =
        vks::initializers::pipelineDepthStencilStateCreateInfo(
            VK_TRUE, VK_TRUE, 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);

    std::array<VkPipelineShaderStageCreateInfo, 2> shaderStages;

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

    // Vertex bindings an attributes
    std::vector<VkVertexInputBindingDescription> vertexInputBindings = {
        vks::initializers::vertexInputBindingDescription(
            0, vertexLayout.stride(), VK_VERTEX_INPUT_RATE_VERTEX),
    };
    std::vector<VkVertexInputAttributeDescription> vertexInputAttributes = {
        vks::initializers::vertexInputAttributeDescription(
            0, 0, VK_FORMAT_R32G32B32_SFLOAT, 0), // Location 0: Position
        vks::initializers::vertexInputAttributeDescription(
            0, 1, VK_FORMAT_R32G32B32_SFLOAT,
            sizeof(float) * 3), // Location 1: Color
        vks::initializers::vertexInputAttributeDescription(
            0, 2, VK_FORMAT_R32G32B32_SFLOAT,
            sizeof(float) * 6) // Location 2: Normal
    };

    VkPipelineVertexInputStateCreateInfo vertexInputState =
        vks::initializers::pipelineVertexInputStateCreateInfo();
    vertexInputState.vertexBindingDescriptionCount =
        static_cast<uint32_t>(vertexInputBindings.size());
    vertexInputState.pVertexBindingDescriptions = vertexInputBindings.data();
    vertexInputState.vertexAttributeDescriptionCount =
        static_cast<uint32_t>(vertexInputAttributes.size());
    vertexInputState.pVertexAttributeDescriptions =
        vertexInputAttributes.data();

    pipelineCreateInfo.pVertexInputState = &vertexInputState;
    pipelineCreateInfo.pInputAssemblyState = &inputAssemblyState;
    pipelineCreateInfo.pRasterizationState = &rasterizationState;
    pipelineCreateInfo.pColorBlendState = &colorBlendState;
    pipelineCreateInfo.pMultisampleState = &multisampleState;
    pipelineCreateInfo.pViewportState = &viewportState;
    pipelineCreateInfo.pDepthStencilState = &depthStencilState;
    pipelineCreateInfo.pDynamicState = &dynamicState;
    pipelineCreateInfo.stageCount = static_cast<uint32_t>(shaderStages.size());
    pipelineCreateInfo.pStages = shaderStages.data();

    // Toon render and stencil fill pass
    shaderStages[0] =
        loadShader(getAssetPath() + "shaders/stencilbuffer/toon.vert.spv",
                   VK_SHADER_STAGE_VERTEX_BIT);
    shaderStages[1] =
        loadShader(getAssetPath() + "shaders/stencilbuffer/toon.frag.spv",
                   VK_SHADER_STAGE_FRAGMENT_BIT);

    rasterizationState.cullMode = VK_CULL_MODE_NONE;

    depthStencilState.stencilTestEnable = VK_TRUE;

    depthStencilState.back.compareOp = VK_COMPARE_OP_ALWAYS;
    depthStencilState.back.failOp = VK_STENCIL_OP_REPLACE;
    depthStencilState.back.depthFailOp = VK_STENCIL_OP_REPLACE;
    depthStencilState.back.passOp = VK_STENCIL_OP_REPLACE;
    depthStencilState.back.compareMask = 0xff;
    depthStencilState.back.writeMask = 0xff;
    depthStencilState.back.reference = 1;
    depthStencilState.front = depthStencilState.back;

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

    // Outline pass
    depthStencilState.back.compareOp = VK_COMPARE_OP_NOT_EQUAL;
    depthStencilState.back.failOp = VK_STENCIL_OP_KEEP;
    depthStencilState.back.depthFailOp = VK_STENCIL_OP_KEEP;
    depthStencilState.back.passOp = VK_STENCIL_OP_REPLACE;
    depthStencilState.front = depthStencilState.back;
    depthStencilState.depthTestEnable = VK_FALSE;

    shaderStages[0] =
        loadShader(getAssetPath() + "shaders/stencilbuffer/outline.vert.spv",
                   VK_SHADER_STAGE_VERTEX_BIT);
    shaderStages[1] =
        loadShader(getAssetPath() + "shaders/stencilbuffer/outline.frag.spv",
                   VK_SHADER_STAGE_FRAGMENT_BIT);
    VK_CHECK_RESULT(vkCreateGraphicsPipelines(device, pipelineCache, 1,
                                              &pipelineCreateInfo, nullptr,
                                              &pipelines.outline));
  }

  // Prepare and initialize uniform buffer containing shader uniforms
  void prepareUniformBuffers() {
    // Mesh 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,
                                   &uniformBufferVS, sizeof(uboVS)));

    // Map persistent
    VK_CHECK_RESULT(uniformBufferVS.map());

    updateUniformBuffers();
  }

  void updateUniformBuffers() {
    uboVS.projection = camera.matrices.perspective;
    uboVS.model = camera.matrices.view;
    memcpy(uniformBufferVS.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();
    loadAssets();
    prepareUniformBuffers();
    setupDescriptorSetLayout();
    preparePipelines();
    setupDescriptorPool();
    setupDescriptorSet();
    buildCommandBuffers();
    prepared = true;
  }

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

  virtual void viewChanged() { updateUniformBuffers(); }

  virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay) {
    if (overlay->header("Settings")) {
      if (overlay->inputFloat("Outline width", &uboVS.outlineWidth, 0.05f, 2)) {
        updateUniformBuffers();
      }
    }
  }
};

VULKAN_EXAMPLE_MAIN()