Feedback Results, Bug or Not?


I am not sure if this should be submitted in bugs, while experimenting with feedback I found the following “issue”.

No matter what I tried, I could not achieve the same smoothness as in the top only setup.

TD Version 2023.11340
Windows 10 Version 22H2 (Build 19045.4291)
Nvidia GeForce RTX 3090
Driver Version: 536.23
DriverType: DHC

I can provide more info if needed.

Using a feedback loop on a geometry, with a texture that has feathered edges, when using 32 bit render, results in strange noise that fills the texture.

Trying this with only TOP setup, results in smoother result.

I have attached a file with both setups, an a side by side image comparison of the result on my machine.

Feedback Texture Render.3.toe (4.3 KB)

There are several things at play here, the main one is having Dither enabled in the Render TOP. However, even if you disable that you won’t get exactly the same result due to the differences in your circle TOPs, scaling of the geometry, camera projection and rasterization and blending operations.

Here’s an updated example where I used the same origin circle TOP for both techniques, went for an orthographic camera for 1:1 mapping and adjusted all settings to get the closest to pixel-perfect rendering.
Feedback Texture Render.4.toe (4.4 KB)

So in my understanding, the pattern that dither ads to the render, is added on top each frame of the feedback resulting in the noise pattern appearing around it?

Thank you for the explanation.

That is correct.