Hi. I’m currently trying to render some visual links (lines) with a nice halo-effect.
My lines are produced as quadstrips. What I’m trying to do now is to render the line twice, the second time with a higher width and less alpha.
This looks OK, but my problem is the following: At the nodes where one line is splitted up into many, the halo get’s too opaque. This is because there are many lines on top of each other, so the alpha values are adding up.
The first picture is without halo, so you can see where the lines split up and what causes the problem. The other two pictures show the unwanted effect, with and w/o comments.
I hope this gives a good picture of my problem. I want to get rid of this effect or at least reduce it to a maximum. I guess this should be manageable through blending functions. I already tried some, but couldn’t get the wanted results.
Maybe you guys can help me. Thanks!
P.S.: I also tried the method described in NeHe turoials (lesson 36, radial blurr) but didn’t get this to work. There are some problems, because the lines are not drawn at once and… so the described method above is how I want to solve this problem now. I already spent too much time on the render-to-texture approach. Many thanks guys.