Calvin ✨

It looks like a great idea. I guess the texture keeps local locations of impacts. But how do you use it as mask to render that impact texture? Masking would be low res and looping through them on hlsl is more expensive.

Yeah, it loops through each pixel in the LUT, and accumulates the falloff. It's an alternative to having a full-size render target and unique UV's for the object, which has limited resolution and removes x-amount of calls to DrawMaterialToRenderTarger (which is crazy slow)

Thanks a lot for the explanation. Yeah, it should be way performant compared to rtt probably on any situation where you draw same texture multiple times. Great idea!

I don't think you'll see a perf impact from looping in hlsl here because the branch isn't going to be non-divergent across the pixel group processed by the gpu. I think there's cheaper ways to do this though like splitting into a grid of possible impacts and picking the closest

is going to be non-divergent* oops! Basically it's going to be the same for every pixel (as long as you keep it that way) so each pixel can be executed in parallel Could be something unforseen though so I'd check in renderdoc

There's definitely room for improvement for sure, it's a very basic implementation at the moment. The major downside is I have to do 90% of the work inside the loop body, so as the effect gets more complex/interesting the cost starts to skyrocket.

Are you generating a distance (sqr) field to drive the effect? That's how I'd do it, but splitting it into cells (look at worley noise algorithms) could reduce a lot of the complexity at the cost of precise hits