--- a/ui/ui/graphics.h	Sun Jan 24 19:57:16 2016 +0100
+++ b/ui/ui/graphics.h	Sun Jan 24 22:20:47 2016 +0100
@@ -60,6 +60,7 @@
 
 // drawing functions
 void ui_graphics_color(UiGraphics *g, int red, int green, int blue);
+void ui_draw_line(UiGraphics *g, int x1, int y1, int x2, int y2);
 void ui_draw_rect(UiGraphics *g, int x, int y, int w, int h, int fill);
 void ui_draw_text(UiGraphics *g, int x, int y, UiTextLayout *text);