It turns out the internal coordinate-systems of some of the Quartz Composer geometric primitive patches are orientated in different directions. These two primitives have the X and Y coordinates of their vertices scales along the Z axis in model-space using a very simple GLSL Vertex Shader, but one appears to be rotated at 90deg. to the other along the X-axis. Odd.
24
Sep
11



I’ve had scenarios where gl projection calls, in the context of a plugin, seem reversed from what they should be, and have also seen things mysteriously “flip” when inside of the Render In Image patch. I’m not sure if this is a related issue, or a different thing altogether. What I find odd(er?), is that I usually see a 180 flip when this pops up.