Updated docs and 4-colour test image.HEADmaster

1 files changed, 7 insertions, 1 deletions

diff --git a/doc/README.txt b/doc/README.txt
index 0de321f..1be180a 100755
--- a/doc/README.txt
+++ b/doc/README.txt
@@ -48,4 +48,10 @@ For 4-colour images it generates bit patterns "00" for colour 0 (default black),
 "01" for colour 1 (default red), "10" for colour 2 (default green) and "11" for
 colour 3 (default blue).
 
-The colours used can be controlled by the switches -c0 to -c3.
+The colours used can be controlled by the switches -c0 to -c3.  Note that in
+reality anything that is not colour 1, 2 or 3 is treated as colour 0.
+
+4-colour mode assumes that pixels are double width as well (like on the C64).
+To disable that use the -d switch.
+
+# vim: spell