hw/display/artist: Avoid drawing line when nothing to display

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20200214001303.12873-5-f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

diff --git a/hw/display/artist.c b/hw/display/artist.c
index 97c811b35e3ce4ef8de607103875528c71e81291..54920791165d9fca06d15799833365c1018344d9 100644 (file)
--- a/hw/display/artist.c
+++ b/hw/display/artist.c
@@ -579,6 +579,9 @@ static void draw_line(ARTISTState *s, int x1, int y1, int x2, int y2,
     } else {
         dy = y1 - y2;
     }
+    if (!dx || !dy) {
+        return;
+    }
 
     c1 = false;
     if (dy > dx) {