Purpose
Opcode format | Opcode | Operand Format | Comments |
Extended ASCII | (Background | <ws><IR>,<IG>,<IB>,<IA>[<ws>])
<ws><II>[<ws>]) |
The background
color for the drawing.
The background color index for the drawing. |
I Defines a color by an index into the current color map
The legal range for the intensity integers is from 0, indicating zero intensity, to 255, indicating full intensity. In some cases, it may be desired to overlay a WHIP! data image on top of an already existing screen image. Consequently, clearing the background is not desired. A zero intensity alpha indicates that the background color is totally transparent, and the window is not cleared. A full intensity alpha (255) indicates that the background color is completely opaque, and the color fully overwrites (clears) its background. Alpha values between 0 and 255 indicate that, when the background is drawn, it is blended to a varying degree with the background image.