This is more a conceptional (approach) question then the search for an implemented solution, since I was unable to find proper hints via google or similar.

The problem is as follows:

Given you have a 3D world that is encoded as voxels. So basically you have your 3D matrix were each position in the matrix is either solid or void ( for simplicity ). Now you look with your camera onto this cloud form a given ( in my case fixed for an isometric perspective ) angle. For each non void coordiante I draw an isometric projected block ( due to my choosen fixed camera angle ), while leaving void coordinates empty.

Of corse I want ot omit to draw coordiantes that are not vissible, so I alread exclude coordiantes that the camera would not see. But I also want to omit coordinates that would be hidden by other blocks, which are in the perspective closer to the camera.

I currently solve this by choosing a specifc camera angle that ensures that a block at coordiantes 0,0,0 would occlde a block at -1,-1,-1; -2,-2,-2; -3,-3,-3; and so on ( is that clear enought or should I add an image to explain? ). This is a rather cheap trick but it works and makes rendering faster as I have only to do a trace for each visible coordiante on the screen and draw the first non void coordinate in that trace. I saw this solution also used in Gnomoria for instance.

But I am wondering, if anyone has some keywords or hints if there is a more general approach to solve this occlusion problem without falling back using cheap camera tricks.


1 Answer 1


3D DDA is the algorithm used for this. It is similar to the method used for lighting occlusion in roguelikes.

  • 1
    \$\begingroup\$ Thank you for the hint! Again until you don't know the name of the thing you won't find it. \$\endgroup\$
    – Kailrim
    Oct 8, 2013 at 15:11

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .