OLD function: this drew the cursor only into the current viewport, and
could not handle difffent ortho coordinate systems (ortho had to be
exactly mapped to screen size).
Given a screen point and a triangles array, return the front-most triangle that
contains the given screen x,y position, or null if no triangle contains the
x,y position.
Create a texture from the given pixels in the default Java ARGB int format.
Configure the texture to repeat in both directions and use LINEAR for magnification.
Hold onto this Class for later class.getResource() calls (to load
resources from JAR files, see getInputStream()) and also to get class
name for use in screenshot filenames (see screenShot()).