your patch is missing the js file which writes the obj.
in any case, this is not a simple thing to do.
you need to enable matrixoutput on the gl.isosurf and connect it’s output to the jit.matrix which feeds the prepend quad_grid (instead of the gl.gridshape). you will have to change the dimension settings to make sure they all match up, and even at this point, i’m not sure if it will work because i’m not sure if gl.isosurf implements a proper matrixoutput to work with this js.
maybe someone else has tried this and can say.
either way, not an easy project for a beginner(or otherwise), so good luck.