Rendering at 320x180px and point scaling up?

Is this possible, and how? I want to see sharp, big pixels on my display.

I know I could do this using a post effect shader, but I prefer to have performance extra.

try the ScreenPercentage property, I think it’s in the level’s postprocess.
you won’t see big sharp pixels though, as the pixels get blurred out

That’s the problem unfortunately, I want to disable the bilinear filtering that’s happening during that scaling.

I wonder if you could make a grid of square planes for your pixels then colour each one by sampling the render output of the game?

Probably easier at that point to use the post-process pixelization method mentioned in the OP.

PostProcessUpscale.usf contains multiple upscaling algorithms, one of them (Method 0) doing a simple nearest point sampling without any filtering.
Simply editing this shader would break lots of other effects but there must be some piece of code defining the upscale method for the screen resolution scaling.