Hello. I have looked over the volume visulization techniques\ndocumentation and I still can't make much sense of it.\n\nIt seems the technique here is some form of:\n\nvol3d=patch(isosurface(data,isovalue))\n\nIn the scalar data example they use mri data as the volume,\nthen somehow find the 'skin' on the surface all has an\nisovalue of 5. This makes no sense to me, as looking at the\ndata this is simply not true. What exactly is an isovalue- I\nseem to read it is like a contour line but from the example\nthe skin portion does not seem to be all the points with a\nvalue of 5 (or lower/higher than 5).\n\nIs there a simple clear explanation of what is going on here?\n\nAs a very simple example, take a 20x20x20 zero matrix, and\nput random integers in a 5x5x5 cube in the center. How can I\nplot the surface of this cube, regardless of the values? How\ncan I plot just a wire frame of the surface of the cube?\n\nI have searched but never seem to find any guide on how to\ndo this other than the official documentation, so if someone\ncould point me n the right direction to do simple things to\nbuild my technique on that would be greatly appreciated.