cairoSetSourceRgba: cairoSetSourceRgba
Description
Sets the source pattern within cr to a translucent color. This
color will then be used for any subsequent drawing operation until
a new source pattern is set.Usage
cairoSetSourceRgba(cr, red, green, blue, alpha)
Arguments
red
[numeric]  red component of color
green
[numeric]  green component of color
blue
[numeric]  blue component of color
alpha
[numeric]  alpha component of color
Details
The color and alpha components are floating point numbers in the
range 0 to 1. If the values passed in are outside that range, they
will be clamped.