取消对接时的ImGui Vulkan验证层错误

Question

将ImGui用于Vulkan时，请使用ImGui\u impl\u Vulkan。cpp，imgui\u impl\u glfw。cpp及其各自的标题我没有收到任何验证层错误，但当我使用“停靠”分支和“取消停靠”时，或者换句话说，当我将ImGui窗口从主Vulkan窗口分离（正如您可能猜测的那样，使用GLFW创建）时，我会收到以下错误：

validation layer: vkCmdDrawIndexed(): RenderPasses incompatible between active render pass w/ VkRenderPass 0x243b910000000054[] and pipeline state object w/ VkRenderPass 0x731f0f000000000a[] Attachment 0 is not compatible with 0: They have different formats.. The Vulkan spec states: The current render pass must be compatible with the renderPass member of the VkGraphicsPipelineCreateInfo structure specified when creating the VkPipeline bound to VK_PIPELINE_BIND_POINT_GRAPHICS.

我的命令缓冲区是这样创建的：

void createCommandBuffers() {
    commandBuffers.resize(swapChainFramebuffers.size());

    VkCommandBufferAllocateInfo allocInfo = {};
    allocInfo.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_ALLOCATE_INFO;
    allocInfo.commandPool = commandPool;
    allocInfo.level = VK_COMMAND_BUFFER_LEVEL_PRIMARY;
    allocInfo.commandBufferCount = (uint32_t)commandBuffers.size();

    if (vkAllocateCommandBuffers(device, &allocInfo, commandBuffers.data()) != VK_SUCCESS) {
        throw std::runtime_error("failed to allocate command buffers!");
    }

    for (size_t i = 0; i < commandBuffers.size(); i++) {
        VkCommandBufferBeginInfo beginInfo = {};
        beginInfo.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO;

        if (vkBeginCommandBuffer(commandBuffers[i], &beginInfo) != VK_SUCCESS) {
            throw std::runtime_error("failed to begin recording command buffer!");
        }

        VkRenderPassBeginInfo renderPassInfo = {};
        renderPassInfo.sType = VK_STRUCTURE_TYPE_RENDER_PASS_BEGIN_INFO;
        renderPassInfo.renderPass = renderPass;
        renderPassInfo.framebuffer = swapChainFramebuffers[i];
        renderPassInfo.renderArea.offset = { 0, 0 };
        renderPassInfo.renderArea.extent = swapChainExtent;

        VkClearValue clearColor = { 0.0f, 0.0f, 0.0f, 1.0f };
        renderPassInfo.clearValueCount = 1;
        renderPassInfo.pClearValues = &clearColor;

        vkCmdBeginRenderPass(commandBuffers[i], &renderPassInfo, VK_SUBPASS_CONTENTS_INLINE);

        vkCmdBindPipeline(commandBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, graphicsPipeline);

        VkBuffer vertexBuffers[] = { vertexBuffer };
        VkDeviceSize offsets[] = { 0 };
        vkCmdBindVertexBuffers(commandBuffers[i], 0, 1, vertexBuffers, offsets);

        vkCmdBindIndexBuffer(commandBuffers[i], indexBuffer, 0, VK_INDEX_TYPE_UINT16);

        vkCmdBindDescriptorSets(commandBuffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayout, 0, 1, &descriptorSets[i], 0, nullptr);

        vkCmdDrawIndexed(commandBuffers[i], static_cast<uint32_t>(indices.size()), 1, 0, 0, 0);

        // Bind Dear Imgui pipeline to draw UI elements inside UI box
        if (isImGuiWindowCreated)
        {
            ImGui_ImplVulkan_RenderDrawData(ImGui::GetDrawData(), commandBuffers[i]);
        }

        vkCmdEndRenderPass(commandBuffers[i]);

        if (vkEndCommandBuffer(commandBuffers[i]) != VK_SUCCESS) {
            throw std::runtime_error("failed to record command buffer!");
        }
    }
    isImGuiWindowCreated = false;
}

我这样初始化ImGui：

void initImGui(float width, float height) {
    QueueFamilyIndices Indices = findQueueFamilies(physicalDevice);

    // Setup Dear ImGui context
    IMGUI_CHECKVERSION();
    ImGui::CreateContext();
    ImGuiIO& io = ImGui::GetIO(); (void)io;
    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;
    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;
    //io.Fonts->AddFontFromFileTTF("../../Assets/Fonts/Roboto-Medium.ttf", 16.0f);

    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
    ImGuiStyle& style = ImGui::GetStyle();
    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
    {
        style.WindowRounding = 0.0f;
        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
    }

    io.DisplaySize = ImVec2(width, height);
    io.DisplayFramebufferScale = ImVec2(1.0f, 1.0f);

    // Setup Platform/Renderer bindings
    ImGui_ImplGlfw_InitForVulkan(window, true);
    ImGui_ImplVulkan_InitInfo init_info = {};
    init_info.Instance = instance;
    init_info.PhysicalDevice = physicalDevice;
    init_info.Device = device;
    init_info.QueueFamily = Indices.graphicsFamily.value();
    init_info.Queue = presentQueue;
    init_info.PipelineCache = VK_NULL_HANDLE;
    init_info.DescriptorPool = descriptorPool;
    init_info.Allocator = NULL;
    init_info.MinImageCount = 2;
    init_info.ImageCount = static_cast<uint32_t>(swapChainImages.size());
    init_info.CheckVkResultFn = NULL;
    ImGui_ImplVulkan_Init(&init_info, renderPass);

    // Setup Dear ImGui style
    ImGui::StyleColorsDark();

    VkCommandBuffer commandBuffer = beginSingleTimeCommands();
    ImGui_ImplVulkan_CreateFontsTexture(commandBuffer);
    endSingleTimeCommands(commandBuffer);
    ImGui_ImplVulkan_DestroyFontUploadObjects();
}

这是beginSingleTimeCommands（）的定义

VkCommandBuffer beginSingleTimeCommands() {
    VkCommandBufferAllocateInfo allocInfo = {};
    allocInfo.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_ALLOCATE_INFO;
    allocInfo.level = VK_COMMAND_BUFFER_LEVEL_PRIMARY;
    allocInfo.commandPool = commandPool;
    allocInfo.commandBufferCount = 1;

    VkCommandBuffer commandBuffer;
    vkAllocateCommandBuffers(device, &allocInfo, &commandBuffer);

    VkCommandBufferBeginInfo beginInfo = {};
    beginInfo.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO;
    beginInfo.flags |= VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT;

    vkBeginCommandBuffer(commandBuffer, &beginInfo);

    return commandBuffer;
}

我不知道如何解决这个问题，因为我已经尝试过为ImGui和主应用程序创建不同的RenderPasses，我也尝试过创建不同的CommandBuffers，但这也没有解决问题。有什么建议吗？

编辑：下面是我如何创建RenderPass的：

void createRenderPass() {
    VkAttachmentDescription colorAttachment = {};
    colorAttachment.format = swapChainImageFormat;
    colorAttachment.samples = VK_SAMPLE_COUNT_1_BIT;
    colorAttachment.loadOp = VK_ATTACHMENT_LOAD_OP_CLEAR;
    colorAttachment.storeOp = VK_ATTACHMENT_STORE_OP_STORE;
    colorAttachment.stencilLoadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE;
    colorAttachment.stencilStoreOp = VK_ATTACHMENT_STORE_OP_DONT_CARE;
    colorAttachment.initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;
    colorAttachment.finalLayout = VK_IMAGE_LAYOUT_PRESENT_SRC_KHR;

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

    VkSubpassDescription subpass = {};
    subpass.pipelineBindPoint = VK_PIPELINE_BIND_POINT_GRAPHICS;
    subpass.colorAttachmentCount = 1;
    subpass.pColorAttachments = &colorAttachmentRef;

    VkSubpassDependency dependency = {};
    dependency.srcSubpass = VK_SUBPASS_EXTERNAL;
    dependency.dstSubpass = 0;
    dependency.srcStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
    dependency.srcAccessMask = 0;
    dependency.dstStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
    dependency.dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_READ_BIT | VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;

    VkRenderPassCreateInfo renderPassInfo = {};
    renderPassInfo.sType = VK_STRUCTURE_TYPE_RENDER_PASS_CREATE_INFO;
    renderPassInfo.attachmentCount = 1;
    renderPassInfo.pAttachments = &colorAttachment;
    renderPassInfo.subpassCount = 1;
    renderPassInfo.pSubpasses = &subpass;
    renderPassInfo.dependencyCount = 1;
    renderPassInfo.pDependencies = &dependency;

    if (vkCreateRenderPass(device, &renderPassInfo, nullptr, &renderPass) != VK_SUCCESS) {
        throw std::runtime_error("failed to create render pass!");
    }
} 

和GraphicsPipeline，我对ImGui和主窗口使用相同的RenderPass：renderPass

void createGraphicsPipeline() {
    auto vertShaderCode = readFile("Shaders\\vert.spv");
    auto fragShaderCode = readFile("Shaders\\frag.spv");

    VkShaderModule vertShaderModule = createShaderModule(vertShaderCode);
    VkShaderModule fragShaderModule = createShaderModule(fragShaderCode);

    VkPipelineShaderStageCreateInfo vertShaderStageInfo = {};
    vertShaderStageInfo.sType = VK_STRUCTURE_TYPE_PIPELINE_SHADER_STAGE_CREATE_INFO;
    vertShaderStageInfo.stage = VK_SHADER_STAGE_VERTEX_BIT;
    vertShaderStageInfo.module = vertShaderModule;
    vertShaderStageInfo.pName = "main";

    VkPipelineShaderStageCreateInfo fragShaderStageInfo = {};
    fragShaderStageInfo.sType = VK_STRUCTURE_TYPE_PIPELINE_SHADER_STAGE_CREATE_INFO;
    fragShaderStageInfo.stage = VK_SHADER_STAGE_FRAGMENT_BIT;
    fragShaderStageInfo.module = fragShaderModule;
    fragShaderStageInfo.pName = "main";

    VkPipelineShaderStageCreateInfo shaderStages[] = { vertShaderStageInfo, fragShaderStageInfo };

    VkPipelineVertexInputStateCreateInfo vertexInputInfo = {};
    vertexInputInfo.sType = VK_STRUCTURE_TYPE_PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO;

    auto bindingDescription = Vertex::getBindingDescription();
    auto attributeDescriptions = Vertex::getAttributeDescriptions();

    vertexInputInfo.vertexBindingDescriptionCount = 1;
    vertexInputInfo.vertexAttributeDescriptionCount = static_cast<uint32_t>(attributeDescriptions.size());
    vertexInputInfo.pVertexBindingDescriptions = &bindingDescription;
    vertexInputInfo.pVertexAttributeDescriptions = attributeDescriptions.data();

    VkPipelineInputAssemblyStateCreateInfo inputAssembly = {};
    inputAssembly.sType = VK_STRUCTURE_TYPE_PIPELINE_INPUT_ASSEMBLY_STATE_CREATE_INFO;
    inputAssembly.topology = VK_PRIMITIVE_TOPOLOGY_TRIANGLE_LIST;
    inputAssembly.primitiveRestartEnable = VK_FALSE;

    VkViewport viewport = {};
    viewport.x = 0.0f;
    viewport.y = 0.0f;
    viewport.width = (float)swapChainExtent.width;
    viewport.height = (float)swapChainExtent.height;
    viewport.minDepth = 0.0f;
    viewport.maxDepth = 1.0f;

    VkRect2D scissor = {};
    scissor.offset = { 0, 0 };
    scissor.extent = swapChainExtent;

    VkPipelineViewportStateCreateInfo viewportState = {};
    viewportState.sType = VK_STRUCTURE_TYPE_PIPELINE_VIEWPORT_STATE_CREATE_INFO;
    viewportState.viewportCount = 1;
    viewportState.pViewports = &viewport;
    viewportState.scissorCount = 1;
    viewportState.pScissors = &scissor;

    VkPipelineRasterizationStateCreateInfo rasterizer = {};
    rasterizer.sType = VK_STRUCTURE_TYPE_PIPELINE_RASTERIZATION_STATE_CREATE_INFO;
    rasterizer.depthClampEnable = VK_FALSE;
    rasterizer.rasterizerDiscardEnable = VK_FALSE;
    rasterizer.polygonMode = VK_POLYGON_MODE_FILL;
    rasterizer.lineWidth = 1.0f;
    rasterizer.cullMode = VK_CULL_MODE_BACK_BIT;
    rasterizer.frontFace = VK_FRONT_FACE_CLOCKWISE;
    rasterizer.depthBiasEnable = VK_FALSE;

    VkPipelineMultisampleStateCreateInfo multisampling = {};
    multisampling.sType = VK_STRUCTURE_TYPE_PIPELINE_MULTISAMPLE_STATE_CREATE_INFO;
    multisampling.sampleShadingEnable = VK_FALSE;
    multisampling.rasterizationSamples = VK_SAMPLE_COUNT_1_BIT;

    VkPipelineColorBlendAttachmentState colorBlendAttachment = {};
    // Original.
    colorBlendAttachment.colorWriteMask = VK_COLOR_COMPONENT_R_BIT | VK_COLOR_COMPONENT_G_BIT | VK_COLOR_COMPONENT_B_BIT | VK_COLOR_COMPONENT_A_BIT;
    colorBlendAttachment.blendEnable = VK_TRUE;
    colorBlendAttachment.srcColorBlendFactor = VK_BLEND_FACTOR_SRC_ALPHA;
    colorBlendAttachment.dstColorBlendFactor = VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA;
    colorBlendAttachment.colorBlendOp = VK_BLEND_OP_ADD;
    colorBlendAttachment.srcAlphaBlendFactor = VK_BLEND_FACTOR_SRC_ALPHA;
    colorBlendAttachment.dstAlphaBlendFactor = VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA;
    colorBlendAttachment.alphaBlendOp = VK_BLEND_OP_SUBTRACT;
    // For ImGui.
    /*colorBlendAttachment.blendEnable = VK_TRUE;
    colorBlendAttachment.srcColorBlendFactor = VK_BLEND_FACTOR_SRC_ALPHA;
    colorBlendAttachment.dstColorBlendFactor = VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA;
    colorBlendAttachment.colorBlendOp = VK_BLEND_OP_ADD;
    colorBlendAttachment.srcAlphaBlendFactor = VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA;
    colorBlendAttachment.dstAlphaBlendFactor = VK_BLEND_FACTOR_ZERO;
    colorBlendAttachment.alphaBlendOp = VK_BLEND_OP_ADD;
    colorBlendAttachment.colorWriteMask = VK_COLOR_COMPONENT_R_BIT | VK_COLOR_COMPONENT_G_BIT | VK_COLOR_COMPONENT_B_BIT | VK_COLOR_COMPONENT_A_BIT;*/

    VkPipelineColorBlendStateCreateInfo colorBlending = {};
    colorBlending.sType = VK_STRUCTURE_TYPE_PIPELINE_COLOR_BLEND_STATE_CREATE_INFO;
    colorBlending.logicOpEnable = VK_FALSE;
    colorBlending.logicOp = VK_LOGIC_OP_COPY;
    colorBlending.attachmentCount = 1;
    colorBlending.pAttachments = &colorBlendAttachment;
    colorBlending.blendConstants[0] = 0.0f;
    colorBlending.blendConstants[1] = 0.0f;
    colorBlending.blendConstants[2] = 0.0f;
    colorBlending.blendConstants[3] = 0.0f;

    VkPipelineLayoutCreateInfo pipelineLayoutInfo = {};
    pipelineLayoutInfo.sType = VK_STRUCTURE_TYPE_PIPELINE_LAYOUT_CREATE_INFO;
    pipelineLayoutInfo.setLayoutCount = 1;
    pipelineLayoutInfo.pSetLayouts = &descriptorSetLayout;

    if (vkCreatePipelineLayout(device, &pipelineLayoutInfo, nullptr, &pipelineLayout) != VK_SUCCESS) {
        throw std::runtime_error("failed to create pipeline layout!");
    }

    VkGraphicsPipelineCreateInfo pipelineInfo = {};
    pipelineInfo.sType = VK_STRUCTURE_TYPE_GRAPHICS_PIPELINE_CREATE_INFO;
    pipelineInfo.stageCount = 2;
    pipelineInfo.pStages = shaderStages;
    pipelineInfo.pVertexInputState = &vertexInputInfo;
    pipelineInfo.pInputAssemblyState = &inputAssembly;
    pipelineInfo.pViewportState = &viewportState;
    pipelineInfo.pRasterizationState = &rasterizer;
    pipelineInfo.pMultisampleState = &multisampling;
    pipelineInfo.pColorBlendState = &colorBlending;
    pipelineInfo.layout = pipelineLayout;
    pipelineInfo.renderPass = renderPass;
    pipelineInfo.subpass = 0;
    pipelineInfo.basePipelineHandle = VK_NULL_HANDLE;

    if (vkCreateGraphicsPipelines(device, VK_NULL_HANDLE, 1, &pipelineInfo, nullptr, &graphicsPipeline) != VK_SUCCESS) {
        throw std::runtime_error("failed to create graphics pipeline!");
    }

    vkDestroyShaderModule(device, fragShaderModule, nullptr);
    vkDestroyShaderModule(device, vertShaderModule, nullptr);
}

Answer 1

这个问题似乎发生在您使用ImGUI中的多视图/对接功能时。

当您启用多视图/停靠功能时，ImGUI会自行创建自己的渲染通道、管道等来处理所有ImGUI外部窗口，因此当您将ImGUI窗口拖到主窗口之外时，问题就会出现。正如您在ImGUI Vulkan实现中可能看到的那样，当为内部渲染通道选择表面格式时，它并不接受所有格式。我不知道确切的原因，但内部渲染通道接受的可能格式是代码的这一部分中的格式。因此，基本上，使用VK_COLORSPACE_SRGB_NONLINEAR_KHR颜色空间作为surfaceFormat的另一对匹配项，它返回可用于格式的第一个选项。我解决这个问题的方法是选择曲面的格式，就像它在ImGUI中实现的方式一样，或者换句话说，我的曲面返回我曲面的VK_FORMAT_B8G8R8A8_UNORM标志。据说这个公关解决了这个问题（在评论中，这个人提到了这个问题）。

ImGui的格式如下：

const VkFormat requestSurfaceImageFormat[] = { VK_FORMAT_B8G8R8A8_UNORM, VK_FORMAT_R8G8B8A8_UNORM, VK_FORMAT_B8G8R8_UNORM, VK_FORMAT_R8G8B8_UNORM };