return value for the x coordinate of the center of the first circle, or NULL
return value for the y coordinate of the center of the first circle, or NULL
return value for the radius of the first circle, or NULL
return value for the x coordinate of the center of the second circle, or NULL
return value for the y coordinate of the center of the second circle, or NULL
return value for the radius of the second circle, or NULL
CAIRO_STATUS_SUCCESS, or CAIRO_STATUS_PATTERN_TYPE_MISMATCH if pattern is not a radial gradient pattern.
Gets the gradient endpoint circles for a radial gradient, each specified as a center coordinate and a radius. Since 1.4