prevent Rect::expand() from generating negative coordinates where there were none...

diff --git a/libs/canvas/types.cc b/libs/canvas/types.cc
index 7d7a495df56666f4586a5d006b91702ec29fe530..9d8ed05622f0c8f298866113cdb085a40097a18a 100644 (file)
--- a/libs/canvas/types.cc
+++ b/libs/canvas/types.cc
@@ -95,8 +95,8 @@ Rect
 Rect::expand (Distance amount) const
 {
        Rect r;
-       r.x0 = x0 - amount;
-       r.y0 = y0 - amount;
+       r.x0 = max (0.0, x0 - amount);
+       r.y0 = max (0.0, y0 - amount);
        r.x1 = safe_add (x1, amount);
        r.y1 = safe_add (y1, amount);
        return r;