diff --git a/minui/minui.h b/minui/minui.h
index 767ffcb..bc43bb5 100644
--- a/minui/minui.h
+++ b/minui/minui.h
@@ -36,7 +36,7 @@
 void gr_fb_blank(bool blank);
 
 void gr_color(unsigned char r, unsigned char g, unsigned char b, unsigned char a);
-void gr_fill(int x, int y, int w, int h);
+void gr_fill(int x1, int y1, int x2, int y2);
 int gr_text(int x, int y, const char *s);
  void gr_texticon(int x, int y, gr_surface icon);
 int gr_measure(const char *s);