我正在与https://vulkan-tutorial.com/ https://vulkan-tutorial.com/深度缓冲代码作为基础。进行了一些更改以每帧更新命令缓冲区。
我正在使用一种粗略的方法来检查 fps。不确定它到底有多准确,但我正在对 fps 使用此检查。
static auto startTime = std::chrono::high_resolution_clock::now();
auto currentTime = std::chrono::high_resolution_clock::now();
float time = std::chrono::duration<float, std::chrono::seconds::period>(currentTime - startTime).count();
if (time < 1)
{
counter++;
}
else
{
int a = 34; //breakpoint put here to check the counter fps.
}
任何没有每帧纹理的方式(命令缓冲区仍在每帧更新。) fps 约为 3500 fps。如果我尝试更新每帧的纹理,fps 会下降到 350 fps。
这只是带有空白纹理的测试代码,但这是我第一次使用上传纹理并更新它的过程。
void createTextureImage()
{
int Width = 1024;
int Height = 1024;
VkDeviceSize imageSize = Width * Height * sizeof(Pixel);
PixelImage.resize(Width * Height, Pixel(0xFF, 0x00, 0x00));
VkBuffer stagingBuffer;
VkDeviceMemory stagingBufferMemory;
createBuffer(imageSize, VK_BUFFER_USAGE_TRANSFER_SRC_BIT, VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT, stagingBuffer, stagingBufferMemory);
void* data;
vkMapMemory(device, stagingBufferMemory, 0, imageSize, 0, &data);
memcpy(data, PixelImage.data(), static_cast<size_t>(imageSize));
vkUnmapMemory(device, stagingBufferMemory);
createImage(Width, Height, VK_FORMAT_R8G8B8A8_SRGB, VK_IMAGE_TILING_OPTIMAL, VK_IMAGE_USAGE_TRANSFER_DST_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, textureImage, textureImageMemory);
transitionImageLayout(textureImage, VK_FORMAT_R8G8B8A8_SRGB, VK_IMAGE_LAYOUT_UNDEFINED, VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL);
copyBufferToImage(stagingBuffer, textureImage, static_cast<uint32_t>(Width), static_cast<uint32_t>(Height));
transitionImageLayout(textureImage, VK_FORMAT_R8G8B8A8_SRGB, VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL, VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL);
vkDestroyBuffer(device, stagingBuffer, nullptr);
vkFreeMemory(device, stagingBufferMemory, nullptr);
}
void UpdateTexture()
{
VkDeviceSize imageSize = 1024 * 1024 * sizeof(Pixel);
memset(&PixelImage[0], 0xFF, imageSize);
VkBuffer stagingBuffer;
VkDeviceMemory stagingBufferMemory;
createBuffer(imageSize, VK_BUFFER_USAGE_TRANSFER_SRC_BIT, VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT, stagingBuffer, stagingBufferMemory);
void* data;
vkMapMemory(device, stagingBufferMemory, 0, imageSize, 0, &data);
memcpy(data, PixelImage.data(), static_cast<size_t>(imageSize));
vkUnmapMemory(device, stagingBufferMemory);
transitionImageLayout(textureImage, VK_FORMAT_R8G8B8A8_SRGB, VK_IMAGE_LAYOUT_UNDEFINED, VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL);
copyBufferToImage(stagingBuffer, textureImage, static_cast<uint32_t>(1024), static_cast<uint32_t>(1024));
transitionImageLayout(textureImage, VK_FORMAT_R8G8B8A8_SRGB, VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL, VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL);
vkDestroyBuffer(device, stagingBuffer, nullptr);
vkFreeMemory(device, stagingBufferMemory, nullptr);
vkDestroyImageView(device, textureImageView, nullptr);
CreateImageView();
}
我已经尝试了一下,似乎所有写入缓冲区并多次转换布局的操作都真正减慢了速度。
对于更多上下文,这是更新纹理过程的其余部分。
UpdateTexture();
for (size_t i = 0; i < vulkanFrame.size(); i++)
{
VkDescriptorBufferInfo bufferInfo = {};
bufferInfo.buffer = uniformBuffers[i];
bufferInfo.offset = 0;
bufferInfo.range = sizeof(UniformBufferObject);
VkDescriptorImageInfo imageInfo = {};
imageInfo.imageLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
imageInfo.imageView = textureImageView;
imageInfo.sampler = textureSampler;
std::array<VkWriteDescriptorSet, 2> descriptorWrites = {};
descriptorWrites[0].sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET;
descriptorWrites[0].dstSet = descriptorSets[i];
descriptorWrites[0].dstBinding = 0;
descriptorWrites[0].dstArrayElement = 0;
descriptorWrites[0].descriptorType = VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER;
descriptorWrites[0].descriptorCount = 1;
descriptorWrites[0].pBufferInfo = &bufferInfo;
descriptorWrites[1].sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET;
descriptorWrites[1].dstSet = descriptorSets[i];
descriptorWrites[1].dstBinding = 1;
descriptorWrites[1].dstArrayElement = 0;
descriptorWrites[1].descriptorType = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER;
descriptorWrites[1].descriptorCount = 1;
descriptorWrites[1].pImageInfo = &imageInfo;
vkUpdateDescriptorSets(device, static_cast<uint32_t>(descriptorWrites.size()), descriptorWrites.data(), 0, nullptr);
}
另外,对于 2D 游戏的空白更新屏幕来说,良好的基本 fps 是多少。我还使用 vulkan 进行 3d 制作,但我也想用它来做复古 2d 的东西。