procedure attribs: set graphics attributes via dialog
link attribs
February 17, 1997; Ralph E. Griswold
Requires: Version 9 graphics
This file is in the public domain.
This procedure produces a dialog in which the user can change the most commonly used graphics attributes. Problems: If a text-entry field is not long enough to hold the current value for an attribute, the attribute has to be edited. Also, a slider is not the best way of changing the gamma attribute -- it's not possible to set a precise value. A slider was used mostly for demonstration purposes.