+static void set_source_rgba(struct graphics_context *gc, double r, double g, double b, double a)
+{
+ if (gc->printer) {
+ /* Black is white and white is black */
+ double sum = r+g+b;
+ if (sum > 2)
+ r = g = b = 0;
+ else if (sum < 1)
+ r = g = b = 1;
+ }
+ cairo_set_source_rgba(gc->cr, r, g, b, a);
+}
+
+static void set_source_rgb(struct graphics_context *gc, double r, double g, double b)
+{
+ set_source_rgba(gc, r, g, b, 1);
+}
+