- defined separate xytype and ztype enums
- only calculate sizes of and render things that we have specified in args
- added lateral scale rendering controls: taken from pixmap.c from the most
  part


git-svn-id: svn://svn.code.sf.net/p/gwyddion/code/trunk/gwyddion@16658 25697fe4-d644-49b8-9d30-be5465f2adf3