Is there any tool out there that will do this?
Im asking because im trying to implement it myself but im really failing terribly, and some advice is what I need.
The problem is simple to explain, you a) edge collapse the model to a desired count then b) raster the displacement map and thats about it, but little complications get in the way like an unclean output, slowness of the algorythm (youd like to get it as quick as possible) you can raytrace it and you can raster it, but its definitely tricky to do.
I realize zbrush can do this, I think, but theres no help on the zbrush site of how to actually go about doing this, I was thinking maybe theres another program that does this that explains itself on the webpage a little more fully to help me out?

Anyway, thanks for any links or advice.

Is there any tool out there that will do this?
Im asking because im trying to implement it myself but im really failing terribly, and some advice is what I need.
The problem is simple to explain, you a) edge collapse the model to a desired count then b) raster the displacement map and thats about it, but little complications get in the way like an unclean output, slowness of the algorythm (youd like to get it as quick as possible) you can raytrace it and you can raster it, but its definitely tricky to do.
I realize zbrush can do this, I think, but theres no help on the zbrush site of how to actually go about doing this, I was thinking maybe theres another program that does this that explains itself on the webpage a little more fully to help me out?

Anyway, thanks for any links or advice.

I believe that the free program xNormal does this.

I know that Simplygon keeps track of the mapping between the surfaces when simplifying so it can then easily compute perfect normal/displacement maps without any raycasting... it is however not cheap :/ The surface mapping is pretty complicated, which explains why it is not used by any other programs that I know of.

Just got surface mapping to work in my simplifier: Left: high poly (8k triangles), middle is low poly (474 triangles) and right is high poly mapped onto the surface of the low poly. This will allow me to compute a displacement map. The mapping is computed while the simplification is performed and always produces a valid mapping.