negative sides of clipping planes?

    Aug 16 2009 | 11:49 am
    Hi everyone,
    A little trouble with clipping planes. A while Ago I asked about (naively) using them within to affect (to which jkc said this was a misuse...I apologize for this continued misuse, but I can't do all this within Well, I'm still at it, and I've greatly simplified what I need into something that works and seems semi-elegant, with one glaring exception: when I want the "streaks" of turning the render's erase_color to , for example, "erase_color 0. 0. 0. .1".
    When I do that, it works fine if the clipping plane has all positive coefficients. But if I want to clip on the "negative" side of the plane (by turning one of the coefficients negative), I get the pure white-out of no erase_color translucency. See below for simple example.
    Is there another way to define which side of a clipping plane the clipping should actually occur on? (and then be able to use all positive coefficients) or am I just missing something with the math, etc?
    Thanks for any help... Dan