Syntax
[C/C++:]
int gSetXORColour(float red, float green, float blue);
[F90:]
subroutine gSetXORColour(red, green, blue)
real, intent (in) :: red,green,blue
Arguments
red
Red intensity, 0.0 to 1.0
green
Green intensity, 0.0 to 1.0
blue
Blue intensity, 0.0 to 1.0
Description
The routine gSetXORColour() defines the actual drawing colour when drawing in XOR mode in terms of its red, green and blue componemts.
This differs from the standard setting of line colour (gSetLineColour()) when drawing in XOR mode, which results in a different colour being displayed on the output device than the colour specified. This is due to the device calculating new red, green, blue components by XOR'ing the bit patterns of the specified colour and the background colour. This is required when the desired effect of drawing over the same line with the same colour is that the background is restored.
In the case of gSetXORColour(), GINO prempts this calculation by calculating new red, green and blue components that will result in the original specified colour when XOR'ed against the background. Redrawing the same line with the same colour using this routine, will simply result in the coloured line remaining on the output device.
See Also
gTrueCol UsagegEnqRGBgSetColourInfogSetLineColourgSetPenType
