233 GCOL Purpose This statement sets the colour to be used by all subsequent graphics operations. In other words it selects the graphics foreground colour and the graphics background colour. It also specifies how the colour is to be placed on the screen. The colour can be plotted directly, ANDed, ORed or Exclusive-ORed with the colour already there, or the colour there can be inverted (reversed). The first number specifies the mode of action as follows:
0 Plot the colour specified 1 OR the specified colour with that already there 2 AND the specified colour with that already there 3 Exclusive-OR the specified colour with that already there 4 Invert the colour already there The second number defines the logical colour to be used in future. If the number is greater than 127 then it defines the graphics background colour. If the number is less than 128 then it defines the graphics foreground colour. See the keyword COLOUR for more information. Examples 100 GCOL 0,2 GCOL 3,129 Description This statement is used to select the logical colours used by graphics statements. Syntax GCOL , Associated keywords CLS , CLG , MODE , COLOUR , PLOT