# Tracing conic surface through voxel grid

I have a voxel grid and a conic surface (hollow cone) placed in the grid.

I want to know which voxels intersect with the cone surface and how much.

So far I have tried sampling points on the conic surface and then match them to the voxels but this solution is quiet cumbersome.

Is there some cone tracing algorithm that would only consider the surface of it?

• When you say "how much" what do you mean? how far it is away from the center of the voxel? Or how much volume of the voxel is inside the cone? Oct 6, 2022 at 9:13
• How far is it from the center of the voxel. Oct 6, 2022 at 9:23
• by having the hessian plane equation you can use the dot product to calculate the distance of a point to a plane. So when each triangle stores it's plane equation (vec4) you can easily calculate the distance to the voxels center. To figure out which voxel is hit, you can use rasterization technique and render from all three sides (x, y and z direction). when doing so, deactivate culling and depthtest Oct 6, 2022 at 9:57
• Hmm, I have an analytical representation of the cone, without any faces. What do you mean by planes? Oct 6, 2022 at 10:24
• ahh okay, I thought the cone is a triangle mesh... so your cone has a position, direction and an opening angle? Oct 6, 2022 at 10:54