color.brightness Function (For GPL Graphic Elements)

Note: If you are modifying the brightness for a guide, refer to color.brightness Function (For GPL Guides) .

Syntax

color.brightness(<algebra>)

or 

color.brightness(color.brightness."brightness value")

or 

color.brightness(<statistic function>)

<algebra>. Graph algebra, using one variable or a blend of variables. Each variable value results in a different level of color brightness.

"brightness value". A value between 0 and 1 that indicates the level of brightness. A value of 1 indicates full brightness, while a value of 0 indicates no brightness (black).

<statistic function>. A statistic function.

Description

Controls the color brightness of the graphic elements. To specify the color brightness explicitly for the fill or border of the graphic element, you can append .interior or .exterior to the function. Using color.brightness without a qualifier implies color.brightness.interior.

Examples

Figure 1. Example: Using the values of a variable to control color brightness
ELEMENT: point(position(x*y), color.brightness(z), color(color.blue))
Figure 2. Example: Using a statistical function to control color brightness
ELEMENT: interval(position(summary.mean(jobcat*salary)), 
         color.brightness(summary.count()))

Statistic Functions

See GPL Functions .