I'm trying to draw a picture on detected marker, like FrameMarkers demo does. The picture is a textured rectangle. I have a problem with it: when I move camera a little bit farther from marker, it starts to... flicker, of sort. it's like corners of the rectangle are cut away, and the size of "cut" area varies from frame to frame:
I draw it as triangle strip on four vertices. What could be causing this problem?