--- a/ui/gtk/draw_gdk.c	Sun Jan 24 19:57:16 2016 +0100
+++ b/ui/gtk/draw_gdk.c	Sun Jan 24 22:20:47 2016 +0100
@@ -77,6 +77,10 @@
     //gdk_gc_set_rgb_bg_color(g->gc, &color);
 }
 
+void ui_draw_line(UiGraphics *g, int x1, int y1, int x2, int y2) {
+    UiGdkGraphics *gr = (UiGdkGraphics*)g; 
+    gdk_draw_line(gr->widget->window, gr->gc, x1, y1, x2, y2);
+}
 
 void ui_draw_rect(UiGraphics *g, int x, int y, int w, int h, int fill) {
     UiGdkGraphics *gr = (UiGdkGraphics*)g;