Allow PixelBuffers to be const
diff --git a/common/rfb/Cursor.cxx b/common/rfb/Cursor.cxx
index 62b767f..8ef8b17 100644
--- a/common/rfb/Cursor.cxx
+++ b/common/rfb/Cursor.cxx
@@ -82,7 +82,7 @@
   mask.buf = outlined.mask.buf; outlined.mask.buf = 0;
 }
 
-rdr::U8* Cursor::getBitmap(Pixel* pix0, Pixel* pix1)
+rdr::U8* Cursor::getBitmap(Pixel* pix0, Pixel* pix1) const
 {
   bool gotPix0 = false;
   bool gotPix1 = false;
@@ -182,7 +182,7 @@
 {
 }
 
-const rdr::U8* RenderedCursor::getBuffer(const Rect& _r, int* stride)
+const rdr::U8* RenderedCursor::getBuffer(const Rect& _r, int* stride) const
 {
   Rect r;