[jitter] Re: [jit.gl.texture @repeat mode]

I'm not sure, but my guess is, since most textures are square (128, 256, 512, 1024, 2048) or a combination of these, like 512x256, the rectangle 0 tells jit.gl.texture not to expect a texture in those proportions. 
With rectangle 0, and the matrix set to 640x480, it works for me, but maybe your graphics card objects to that... I'm no expert on these matters.