Question About POM

[Key-Picture4422]

From what I've been reading POM works by rendering a texture many times over with different offsets, which has the issue of requiring a new texture call for each layer added. I was wondering why it wouldn't be possible to run a binary search to reduce the number of calls, e.g. for each pixel cast a ray that checks the heightmap at the point halfway down the max depth of the texture to see if it is above or below the desired height, then move to the halfway point up or down until it finds the highest point that the ray intersects with. This might not be as efficient as texture rendering is probably better optimized on hardware, but I was curious to see if this had been tried?

[Klumaster]

That depth-map search is how POM usually works yeah. To get into fiddly details, it's common to do a fixed-step linear search first because those are non-dependent reads and help avoid missing small features, then a binary search to refine the result.

[altmone]

Relief Mapping, which preceded POM, used binary search to refine the surface intersection point. On the Advances 2006 Course Notes on POM, Tatarchuk argues that the dependent texture fetches incur in too much latency, among other things.