Antialiased "fat" connected lines

Hi all,

I want to draw an antialiased linestrip with big line width (e.g. 12.0) in a transparent color (A=0.4).

At the connecting vertices there are rifts and overlapping regions. So the shape of the linepiece connections and the inhomegenous color there need more attention.

I spend a lot of time to try many things with and without introduced points, stencilBuffer, alpha functions and blending, but without perfect results.

What’s a general working algorithm for this problem?

Many thanks for each answer!
Ralf

two things:

  1. If you might use antialiasing for smoothing your lines, but this has to be supported by your video card.

  2. look in the OpenGL spec to understand how lines are rendered, you might get a clue what to againts your prob.