17.10 Win32 Graphics

MIT/GNU Scheme supports graphics on Microsoft Windows 95, Windows 98, and Windows NT. In addition to the usual operations, there are operations to control the size, position and colors of a graphics window. Win32 devices support images, which are implemented as device independent bitmaps (DIBs).

The Win32 graphics device type is implemented as a top level window. graphics-enable-buffering is implemented and gives a 2x to 4x speedup on many graphics operations. As a convenience, when buffering is enabled clicking on the graphics window’s title bar effects a graphics-flush operation. The user has the benefit of the increased performance and the ability to view the progress in drawing at the click of a mouse button.