Translucent Point Cloud with strange "back face culling"

Scripting
,
1

I am drawing point cloud to represent object density and the point display in very different way denpending on viewing angle.
Each point has an alpha value assigned from 1 to 0. I expect a fuzzy, translucent point cloud.
var col = new Rhino.Display.ColorHSL(alpha, hue, 1, 0.5).ToArgbColor();
var pt = grid[i, j, k];
pointCloud.Add(pt, col);
Which is what it appears from some view angle, but when I rotate the view and view it from the opposite direction, points in the front would hide points on the back, until at an angle where everything is completely transparent. I suspect it has to do with backface culling of transparent points. Anyone has similar experience/solution?

2

Hi @Anthony_Chu,

Can you provide some sample code, so we can run in it here, that reproduces the behavior you are seeing?

– Dale