Storing directions in distance fields

Unity Engine
1

Hi all,

I’m looking into distance fields as a solution for some custom collisions.

Some of what I read has the distance field as a 3 dimensional array of signed distance float values, to calculate the position of the closest point on a surface given a point the field is sampled multiple times at that point with small deltas to get a gradient and determine the position from that.

Other than having 4x the data, is there any reason I couldn’t/shouldn’t have my distance field data be arrays of Vector4s, where x,y,z represents the vector from the point to the surface, using w for signed distance?

2

Rebuilding the distance field will also be that more expensive as well.

What sort of collisions are you looking into simulating that you need a distance field, and that you need this directions so readily available?

3

Along the lines of biasing particle movement towards static surfaces and bouncing them off.
In my case rebuilding will (usually) be offline so that shouldn’t be a problem but yeah that’s a good point in the general case. It’s just not something I’ve come across when googling, and I would have expected to.