untold vale
Vulkan 1.4
Theme: Dynamic rendering and input attachments
Hello. In my personal project i started to move from render passes and subpasses to dynamic rendering. Everything goes smoothly, until I reach moment wheren i need implement input attachments.
In my renderer i specify render graph, and then record command buffers from it. Command reocrding look something like this:
for(pass: passes)
{
// barriers for color, depth, stencil and input attachments:
vkCmdPipelineBarrier2
vkCmdBeginRendering
//render commands
vkCmdEndRendering
}
In render graph i can specify color,depth, stencil and input attachment, then for each pass which uses attachment I transfer its layouts to correct layout. But in dynamic rendering there is no way to specify input attachments, so my first idea (which i found somewhere) to transfer attachmnets to shader read only layout and use it as combined image sampler descriptor. But I do not like this solution.
So next thing I found is VK_KHR_dynamic_rendering_local_read extension which fortunetly is now in 1.4 standard, and look promising, but i do not know if I understand it correctly.
What i understand from this blog post https://www.khronos.org/blog/streamlining-subpasses is that each color, depth and stencil attachment from VkRenderingInfo can be used as input attachment, and what we need to do is to just bind descriptor with descriptor type VK_DESCRIPTOR_TYPE_INPUT_ATTACHMENT and use VK_IMAGE_LAYOUT_RENDERING_LOCAL_READ for input attachments, then add barier (like in post) before draw commands which use input attachments and we are done. Then in shaders we do not need to specify input_attachment_index for binded descriptors,:
layout(set = 0, binding = 0) uniform subpassInput InputAtt1
