The main goal of this rewrite was to make the code
simpler and easier to maintain.
The API is mostly unchanged, however there are some differences.
- we now have the concept of subresources, e.g. for Textures, as
subresource is a mip level or layer.
- RenderTargets are no longer resources, instead they are transiant
objects associated to a pass and are now called RenderPasses.
- RenderPasses take subresources for attachments.
- We have better validation of graph building.
We should also compute discard flags more accurately.
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