[jitter] bug with jit.gl.sketch and glloadidentity

Hi Pelado,
Here's what you need to do:

reset, glclearcolor 1 0 0 1, glclear, glmatrixmode modelview,
glpushmatrix, glloadidentity, gltranslate -0.4 0 -2, glrotate $1 0 1
0, cube 0.2, glpopmatrix, gldisable depthtest, glenable blend,
glblendfunc 6 1, glcolor 1 1 0 0.5, glpushmatrix, glloadidentity,
gltranslate 0.8 0 -2, glrotate 90 0 1 0, cube 0.2,, glpopmatrix

In your patch you were rendering the cubes exactly at z=0 i.e. at the
location with the camera.  This is what happens when you cal
glLoadIdentity() without offsetting in the Z direction.

wes