In the image below, the sign on the side of the van is not face-on to the camera. I want to calculate, as best I can with the pixels I have, what it'd look like face on.

I imagine that this is some kind of loop through the x and y axis doing a Bresenham's line on both dimensions at once with some kind of mixing when pixels in the source image overlap - some sub-pixel mixing of some sort?

What approaches are there, and how do you mix the pixels?

Is there a standard approach for this?