findtile.icn: Program to find tiles in an image

This program is designed to assist in locating areas within an image
that, when tiled, produce a desired effect.  For example, a background
may consist of a tiled image; this program can be used to find the
smallest tile for the repeat (by "eye-balling").  It's worth noting
that interesting images can be found for other settings.  For example,
another interesting use of this program is to produce striped patterns by
selecting a row or column of an image to get a tile that is one character
wide.  Sometimes a few rows or columns give an interesting "fabric"
effect.

There are three windows:

     the VIB control window
     the source image window
     a repeat window, which shows the selection from the source
       image, tiled.

The selection from the source image is shown as a marquee in the
source image window.  When a source image is loaded, the marquee starts
with the entire image.  The marquee can be changed by buttons and
arrow-key events on the control window (not the source image window).

The arrow keys have two modes.  With no modifier, they nudge the
location of the marquee.  With the meta-key modifier, they nudge
the dimensions of the marquee.

The reset button resets the marquee to the entire image.

The current selection can be mirrored using the mirror button.

The following features are provided through keyboard shortcuts:
the File menu, and in some cases, on-board buttons:

     @O      open new source image
     @Q      quit application
     @S      save current selection as an image
     @Z      set size precisely

The repeat window can be resized by the user, but it is not redrawn
until the marque is changed or the refresh button is pushed.