I am trying to make two simple subpasses where the second has a dependency on the first.
//subpass 1
VkAttachmentReference colorReferences = { 0, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL };
VkSubpassDescription subpass1 = {};
subpass1.pipelineBindPoint = VK_PIPELINE_BIND_POINT_GRAPHICS;
subpass1.pColorAttachments = &colorReferences;
subpass1.colorAttachmentCount = 1;
//subpass 2
VkAttachmentReference inputRefernce = { 0, VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL };
VkSubpassDescription subpass2 = {};
subpass2.pipelineBindPoint = VK_PIPELINE_BIND_POINT_GRAPHICS;
subpass2.inputAttachmentCount = 1;
subpass2.pInputAttachments = &inputRefernce;
//Render pass
VkAttachmentDescription attachmentDescs = {};
attachmentDescs.samples = VK_SAMPLE_COUNT_1_BIT;
attachmentDescs.loadOp = VK_ATTACHMENT_LOAD_OP_CLEAR;
attachmentDescs.storeOp = VK_ATTACHMENT_STORE_OP_STORE;
attachmentDescs.stencilLoadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE;
attachmentDescs.stencilStoreOp = VK_ATTACHMENT_STORE_OP_DONT_CARE;
attachmentDescs.format = VK_FORMAT_R16G16B16A16_SFLOAT;
attachmentDescs.initialLayout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
attachmentDescs.finalLayout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
VkSubpassDependency dependency = {};
dependency.srcSubpass = 0;
dependency.dstSubpass = 1;
dependency.srcStageMask = VK_PIPELINE_STAGE_ALL_GRAPHICS_BIT;
dependency.dstStageMask = VK_PIPELINE_STAGE_ALL_GRAPHICS_BIT;
dependency.srcAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
dependency.dstAccessMask = VK_ACCESS_SHADER_READ_BIT;
VkSubpassDescription subpasses[2] = { subpass1, subpass2 };
VkRenderPassCreateInfo renderPassInfo = {};
renderPassInfo.sType = VK_STRUCTURE_TYPE_RENDER_PASS_CREATE_INFO;
renderPassInfo.pAttachments = &attachmentDescs;
renderPassInfo.attachmentCount = 1;
renderPassInfo.subpassCount = 2;
renderPassInfo.pSubpasses = subpasses;
renderPassInfo.dependencyCount = 1;
renderPassInfo.pDependencies = &dependency;
vkUtils::checkResult(vkCreateRenderPass(_context->device, &renderPassInfo, nullptr, &_renderPass));
I have a dependency between the first and second subpass. The specification states:
If the attachment indicates loading VK_ATTACHMENT_LOAD_OP_CLEAR, then it will be logically cleared at the beginning of the first subpass, where it is used.
It will be cleared only at the beginning of the first subpass, in which the attachment is used. And since there is a dependency between them, it should not be cleared in the second subpass.
The first use of the attachment should not indicate a layout equal to VK_IMAGE_LAYOUT_DEPTH_STENCIL_READ_ONLY_OPTIMAL or VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL if the attachment indicates that> loadOp is VK_ATTACHMENT_LOAD_OP_CLEAR. [...]
I get this error at check level:
Cannot clear attachment 0 with invalid first layout VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL.
VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL subpass, ?