Refactor cairo drawing of rectangles into utility functions.

i3bar/include/cairo_util.h

@@ -72,3 +72,20 @@ void cairo_set_source_color(surface_t *surface, color_t color);
  *
  */
 void cairo_draw_text(i3String *text, surface_t *surface, color_t fg_color, color_t bg_color, int x, int y, int max_width);
+
+/**
+ * Draws a filled rectangle.
+ * This function is a convenience wrapper and takes care of flushing the
+ * surface as well as restoring the cairo state.
+ * Note that the drawing is done using CAIRO_OPERATOR_SOURCE.
+ *
+ */
+void cairo_draw_rectangle(surface_t *surface, color_t color, double x, double y, double w, double h);
+
+/**
+ * Copies a surface onto another surface.
+ * Note that the drawing is done using CAIRO_OPERATOR_SOURCE.
+ *
+ */
+void cairo_copy_surface(surface_t *src, surface_t *dest, double src_x, double src_y,
+                        double dest_x, double dest_y, double dest_w, double dest_h);