TAA followup tracking issue

[JMS55]

TAA got merged in https://github.com/bevyengine/bevy/pull/7291, but there's a couple of things we could do better.

Compatibility

• [x] Write motion vectors for skinned meshes correctly
• [x] Write motion vectors for morph targets correctly
• [ ] Write motion vectors for materials with parallax mapping correctly
• [ ] Support jittering orthographic cameras

Quality

• [x] Mip biasing for sharper textures https://github.com/bevyengine/bevy/pull/7614 https://github.com/bevyengine/bevy/issues/7323
• [ ] Investigate FSR techniques and more advanced TAA disocclusion heuristics to replace the rather naive history confidence mechanism we currently have (https://github.com/GPUOpen-Effects/FidelityFX-FSR2#the-technique, plane validation https://diharaw.github.io/post/adventures_in_hybrid_rendering)
• [ ] Extra input filter to improve sharpness (Blackman-Harris or Mitchell-Netravali)
• [ ] Flicker reduction
• [ ] Investigate YCbCr vs YCoCg
• [ ] Investigate whether variance(clipping) is necessary in YCoCg, vs just min/max clamp or clip
• [ ] Consider moving TAA to be after the opaque pass, but before the transparent pass.

Performance

• [ ] Use a uniform buffer for reset instead of shader defs
• [ ] Move TAA to a compute shader instead of a fragment shader (threads can collaborate to load history and other textures into workgroup shared memory)
• [ ] Double buffer mesh/view transform uniforms, rather than writing new buffers for the past-frame's values each frame
• [ ] Figure out COD's 1-tap bicubic filter https://www.activision.com/cdn/research/Dynamic_Temporal_Antialiasing_and_Upsampling_in_Call_of_Duty_v4.pdf#page=64

[nicopap]

Relevant:

• https://github.com/bevyengine/bevy/pull/8974

[Affinator]

What is missing to implement jittering orthograpic cameras?

When I just remove the check from camera.rs ...

if clip_from_view.w_axis.w == 1.0 {
   warn!(
       "TemporalJitter not supported with OrthographicProjection. Use PerspectiveProjection instead."
   );
   return;
}

... then TAA seems to work (fine)?