Search the Community

We've been experiencing a bug for a while where our tree billboards would flicker black in a really obnoxious way, that looked a lot like z-fighting. Recently though I've tracked it down and discovered that it isn't caused by z-fighting after all. We assumed it was so dark because it was caused by shadowed billboards being sorted incorrectly and showing up in front of other trees, but it's actually a problem with alpha testing not working properly. The first attached image shows this problem manifesting itself in a line. This is the point where the juniperoxy billboard intersects the willow billboard (the tree). You can see this in the second image where alpha test is turned off for the juniperoxy. Looking at the 4th image, you can see it's not just rendering black pixels there, it's actually rendering the transparent portion of the billboard image as opaque. For some reason when two billboard polys intersect in a certain way, it renders part of the image at 100% opaque alpha. In the short term, I've worked around this by painting a green tree pattern into the black portions of the tree billboards, and it's reduced the amount of flickering the user can see, however it's still very noticeable on groups of trees with some color variation. Is there a fix for this? We're on version 2.2.1, btw.

Tried to change Material "Offset" property, no effect when I set it, dunno, maybe I'm doing it wrong. bug is on GeForce 420, 560, Radeon HD 6970 log.html