diff --git a/graphics/HACKING.txt b/graphics/HACKING.txt
index 029439a..2123cc4 100644
--- a/graphics/HACKING.txt
+++ b/graphics/HACKING.txt
@@ -2,7 +2,7 @@
 The Recipe File
 ===============
 
-The `tiles.dat' file is the recipe file for generating the tiles.
+The `tiles.rc' file is the recipe file for generating the tiles.
 It is a plain-text file, where each line begins with a tile id,
 followed by an image specification.
 
@@ -10,8 +10,8 @@ The image specification consists of one or more image layers separated
 by the pipe character (|). The layers are drawn in the order specified.
 
 A layer is a file name (excluding the .png extension), optionally followed
-by @X,Y,W,H, where X,Y specify the upper-left corner of the rectangle to
-draw, and W,H specify the width and height of the rectangle to draw.
+by @X,Y, where X,Y specify the upper-left corner of the rectangle to
+draw.
 
 
 ==============================