cairo-mesh-pattern-set-corner-color-rgba (pattern corner-num red green blue alpha)

pattern -- a cairo-pattern-t instance
corner-num -- an unsigned integer with the corner to set the color for
red -- a double float red component of color
green -- a double float green component of color
blue -- a double float blue component of color
alpha -- a double float alpha component of color

Sets the color of a corner of the current patch in a mesh pattern.

The color is specified in the same way as for the function cairo-set-source-rgba.

Valid values for corner-num are from 0 to 3 and identify the corners as explained for the function cairo-pattern-create-mesh. If pattern is not a mesh pattern then pattern will be put into an error status with a status of :pattern-type-mismatch. If corner-num is not valid, pattern will be put into an error status with a status of :invalid-index. If pattern has no current patch, pattern will be put into an error status with a status of :invalid-mesh-construction.