hw/display/artist: Fix invalidation of lines near screen border

If parts of the invalidated screen lines are outside of the VRAM buffer,
the code skips the whole invalidate. This is incorrect when only parts
of the buffer are invisble - which is the case when the mouse cursor is
located near the screen border.

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>

diff --git a/hw/display/artist.c b/hw/display/artist.c
index a959b2c1583abeba98f54b88e7aac8f527410510..71982559c6e4c3d1ead74dcc863d04c11d1c1daa 100644 (file)
--- a/hw/display/artist.c
+++ b/hw/display/artist.c
@@ -206,7 +206,12 @@ static void artist_invalidate_lines(struct vram_buffer *buf,
                                     int starty, int height)
 {
     int start = starty * buf->width;
-    int size = height * buf->width;
+    int size;
+
+    if (starty + height > buf->height)
+        height = buf->height - starty;
+
+    size = height * buf->width;
 
     if (start + size <= buf->size) {
         memory_region_set_dirty(&buf->mr, start, size);