Problem with translucent materials seen at flat angle

[anonymous_user_07ba773b]

I’m having a strange problem where a translucent material is producing artefacts when seen at a completely flat angle.

I have a simple plane with a material added that has a beam-like texture running across it, with an alpha channel working as the opacity. This works totally fine from normal viewing angles, but as soon as you look at the plane straight on, I get a white line showing the entire width of the plane.

Here is an image demonstrating the problem:

The red lines running across all three images demonstrate what should be the maximum width of the beam from this viewing angle. As the camera starts to tilt so that we’re looking straight along the plane, everything is working fine. However, in the third image you can see what happens when we look straight along the plane - we get a white line which stretches beyond the bounds of the masked section of the translucency, and effectively see the entire width of the plane.

This is a massive problem, because my scene involves a lot of planes with translucent materials on them, and it’s quite common to be looking directly along a plane like this, so there are lots of artefacts jumping all over the place as you look at the scene.

Anyone know what the cause of this is, and how to eliminate it?

Thanks!

[Wilkes]

Is it possible that the distance from the camera to the object is resulting in perspective distortion? IE: as the bottom of the beam gets closer to the camera, it takes up a wider angle of the FOV.

[anonymous_user_07ba773b]

I don’t think so. When the camera is even one pixel above looking at it flat on, it looks correct, but drop down that extra pixel so that you’re looking straight at the edge of the plane and it suddenly jumps in width significantly. When I’m back on my computer I can upload a gif/video showing this.

[anonymous_user_c94f194d]

Anistrophic filtering and mipmaps. It’s better to make texture as small as possible. So trim the excess borders off.