allocateRenderPass :: MonadResource m=> Device-> Vector (Format, ImageLayout)Colour attachments:
(format, finalLayout).-> Maybe FormatOptional depth attachment format.
-> m (ReleaseKey, RenderPass)
A render pass with colors colour attachments (each (format, finalLayout))
and an optional depth attachment, all cleared on load and stored on completion, in
a single graphics subpass. Attachment indices are the colours 0..N-1 then the
depth attachment at N — the colour-then-depth order the framebuffer's
attachments must follow. The external
dependency synchronizes colour output and, when present, the
depth fragment tests.