如何在不更改數據的情況下將 3D VkImage 傳遞給計算着色器？

Question

我試圖將體素的隨機 3D 圖像傳遞給計算着色器，但是當我運行着色器時，整個着色器會導致：

如您所見，這看起來不像是隨機生成的體素，除了第二個體素的前半部分。 老實說，我完全不知道數據發生了什么。 我知道我的計算着色器輸出到交換鏈圖像不是問題，因為我檢查了其他計算着色器（例如噪聲屏幕等）是否可以工作，他們確實可以。 我已經將錯誤的位置縮小到將數據從我的std::vector<std::vector<std::vector<glm::vec4>>> voxelImage到voxelImage或者它可能正在傳遞該voxelImage到計算着色器。

我還檢查了體素的生成不僅僅是生成屏幕上看到的內容。 vec4s 的向量確實是隨機的，我保證錯誤出現在我將其縮小到的兩個地方中的任何一個。

我只會發布創建voxelImage和voxelImageView的代碼，以及可能發生錯誤的描述符。 （發布其余的代碼會不必要地過多，而且會太長）

體素圖像創建：

void createVoxelImage() {

        VkDeviceSize imageSize = voxelDataInit.size();



        VkBuffer stagingBuffer;
        VkDeviceMemory stagingBufferMemory;
        VmaAllocation stagingAllocation;
        createBuffer(imageSize, VK_BUFFER_USAGE_TRANSFER_SRC_BIT, VMA_MEMORY_USAGE_GPU_ONLY, VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT, stagingBuffer, stagingAllocation, stagingBufferMemory);

        void* data;
        vmaMapMemory(allocator, stagingAllocation, &data);
        memcpy(data, &voxelDataInit, imageSize);
        vmaUnmapMemory(allocator, stagingAllocation);

        
        
       
        VkDeviceMemory temp; 
        createImage(voxWidth, voxHeight, voxDepth, VK_IMAGE_TYPE_3D, VK_FORMAT_R8G8B8A8_SRGB, VK_IMAGE_TILING_OPTIMAL, VK_IMAGE_USAGE_TRANSFER_DST_BIT | VK_IMAGE_USAGE_STORAGE_BIT, VK_IMAGE_LAYOUT_UNDEFINED, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, voxelImage, voxelAllocation, VMA_MEMORY_USAGE_GPU_ONLY, temp, 5);
        //vkFreeMemory(device, temp, NULL);

        //VkDeviceMemory temp;
        //createImage(voxWidth, voxHeight, voxDepth, VK_IMAGE_TYPE_3D, VK_FORMAT_B8G8R8_UNORM, VK_IMAGE_TILING_OPTIMAL, VK_IMAGE_USAGE_STORAGE_BIT, VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT, voxelImage, voxelAllocation, VMA_MEMORY_USAGE_CPU_TO_GPU, temp, 5);

        transitionImageLayout(voxelImage, VK_FORMAT_R8G8B8A8_SRGB, VK_IMAGE_LAYOUT_UNDEFINED, VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL, VK_ACCESS_TRANSFER_READ_BIT, VK_ACCESS_TRANSFER_WRITE_BIT, VK_PIPELINE_STAGE_TOP_OF_PIPE_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT);
        copyBufferToImage(stagingBuffer, voxelImage, static_cast<uint32_t>(voxWidth), static_cast<uint32_t>(voxHeight), static_cast<uint32_t>(voxDepth));
        transitionImageLayout(voxelImage, VK_FORMAT_R8G8B8A8_SRGB, VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL, VK_IMAGE_LAYOUT_GENERAL, VK_ACCESS_TRANSFER_WRITE_BIT, VK_ACCESS_SHADER_READ_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT, VK_PIPELINE_STAGE_COMPUTE_SHADER_BIT);

        vmaDestroyBuffer(allocator, stagingBuffer, stagingAllocation);

    }

體素圖像視圖創建：

void createVoxelImageView() {
        VkImageViewCreateInfo viewInfo{};
        viewInfo.sType = VK_STRUCTURE_TYPE_IMAGE_VIEW_CREATE_INFO;
        viewInfo.image = voxelImage;
        viewInfo.viewType = VK_IMAGE_VIEW_TYPE_3D;
        viewInfo.format = VK_FORMAT_R8G8B8A8_SRGB;
        //viewInfo.flags = VK_FORMAT_FEATURE_STORAGE_IMAGE_BIT;
        viewInfo.subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
        viewInfo.subresourceRange.baseMipLevel = 0;
        viewInfo.subresourceRange.levelCount = 1;
        viewInfo.subresourceRange.baseArrayLayer = 0;
        viewInfo.subresourceRange.layerCount = 1;

        
        
        if (vkCreateImageView(device, &viewInfo, nullptr, &voxelImageView) != VK_SUCCESS) {
            throw std::runtime_error("Failed to create image view! (voxel)");
        }
    }

數據輸入到着色器

layout(binding = 4, rgba8) uniform image3D voxels;

的防守力createImage ：

void createImage(uint32_t width, uint32_t height, uint32_t depth, VkImageType imgType, VkFormat format, VkImageTiling tiling, VkImageUsageFlags usage, VkImageLayout layout, VkMemoryPropertyFlags properties, VkImage& image, VmaAllocation& allocation, VmaMemoryUsage memUsage, VkDeviceMemory& imageMemory, int callNum) {
        VkImageCreateInfo imageInfo{};
        imageInfo.sType = VK_STRUCTURE_TYPE_IMAGE_CREATE_INFO;
        imageInfo.imageType = imgType;
        imageInfo.extent.width = width;
        imageInfo.extent.height = height;
        imageInfo.extent.depth = depth;
        imageInfo.mipLevels = 1;
        
        imageInfo.arrayLayers = 1;
        imageInfo.format = format;
        imageInfo.tiling = tiling;
        imageInfo.initialLayout = layout;
        imageInfo.usage = usage;
        imageInfo.samples = VK_SAMPLE_COUNT_1_BIT;
        imageInfo.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
        imageInfo.flags = VK_FORMAT_FEATURE_STORAGE_IMAGE_BIT;

        VmaAllocationCreateInfo vmaAllocInfo = {};
        vmaAllocInfo.usage = memUsage;
        vmaAllocInfo.requiredFlags = VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;


        if (vmaCreateImage(allocator, &imageInfo, &vmaAllocInfo, &image, &allocation, nullptr) != VK_SUCCESS) {
            throw std::runtime_error(std::to_string(callNum));
            throw std::runtime_error("failed to create image!");
        }
    }

的防守transitionImageLayout ：

void transitionImageLayout(VkImage image, VkFormat format, VkImageLayout oldLayout, VkImageLayout newLayout, VkAccessFlagBits srcAccess, VkAccessFlagBits dstAccess, VkPipelineStageFlagBits srcStage, VkPipelineStageFlagBits dstStage) {
        VkCommandBuffer commandBuffer = beginSingleTimeCommands();

        VkImageMemoryBarrier barrier{};
        barrier.sType = VK_STRUCTURE_TYPE_IMAGE_MEMORY_BARRIER;
        barrier.oldLayout = oldLayout;
        barrier.newLayout = newLayout;
        barrier.srcQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
        barrier.dstQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
        barrier.image = image;
        barrier.subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
        barrier.subresourceRange.baseMipLevel = 0;
        barrier.subresourceRange.levelCount = 1;
        barrier.subresourceRange.baseArrayLayer = 0;
        barrier.subresourceRange.layerCount = 1;
        

        VkPipelineStageFlags sourceStage;
        VkPipelineStageFlags destinationStage;

        if (oldLayout == VK_IMAGE_LAYOUT_UNDEFINED && newLayout == VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL) {
            barrier.srcAccessMask = 0;
            barrier.dstAccessMask = VK_ACCESS_TRANSFER_WRITE_BIT;

            sourceStage = VK_PIPELINE_STAGE_TOP_OF_PIPE_BIT;
            destinationStage = VK_PIPELINE_STAGE_TRANSFER_BIT;
        }
        
        else {
            if (srcStage == VK_PIPELINE_STAGE_TOP_OF_PIPE_BIT) {
                barrier.srcAccessMask = 0;
            }
            else {
                barrier.srcAccessMask = srcAccess;
            }
            barrier.dstAccessMask = dstAccess;

            sourceStage = srcStage;
            destinationStage = dstStage;
            //throw std::runtime_error("Unsupported layout transition.");
        }

        vkCmdPipelineBarrier(commandBuffer, sourceStage, destinationStage, 0, 0, nullptr, 0, nullptr, 1, &barrier);

        endSingleTimeCommands(commandBuffer);
    }

防守的copyBufferToImage ：

void copyBufferToImage(VkBuffer buffer, VkImage image, uint32_t width, uint32_t height, uint32_t depth){
    VkCommandBuffer commandBuffer = beginSingleTimeCommands();

    VkBufferImageCopy region{};
    region.bufferOffset = 0;
    region.bufferRowLength = 0;
    region.bufferImageHeight = 0;
    
    region.imageSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
    region.imageSubresource.mipLevel = 0;
    region.imageSubresource.baseArrayLayer = 0;
    region.imageSubresource.layerCount = 1;

    region.imageOffset = { 0, 0, 0 };
    region.imageExtent = {
        width,
        height,
        depth
    };

    

    vkCmdCopyBufferToImage(commandBuffer, buffer, image, VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL, 1, &region);

    endSingleTimeCommands(commandBuffer);
}

Answer 1

如果voxelDataInit確實是std::vector<std::vector<std::vector<glm::vec4>>>類型的變量，則memcpy(data, &voxelDataInit, imageSize); 永遠不會工作。 &voxelDataInit是一個指向vector的指針。 指向vector<T>的指針總是相同的大小（忽略分配器本身）：3 個指針的大小。

請記住： vector<T>是指向T數組的指針。 或者更確切地說，它是指向該數組的 3 個指針。 但無論如何， vector<T>本身並不是T的數組； 它只擁有一個。 因此，復制vector的字節不會復制數組本身。

此外， vector的size只是元素的數量，而不是數組中的字節數。

復制這種數據結構的最好方法是停止使用這種數據結構。 如果你想要一個三維數組，然后你想要的是尺寸長×寬×高的一維數組。 您可以通過使用長度、寬度、高度將 3D 坐標轉換為 1D 坐標來索引數組的任何特定 X、Y、Z 分量。