+// bitmap array positions for various element sizes, if available
+//
+// for any loaded image, the "standard" size (which represents the 32x32 pixel
+// size for game elements) is always defined; other bitmap sizes may be NULL
+//
+// formats from 32x32 down to 1x1 are standard bitmap sizes for game elements
+// (used in the game, in the level editor, in the level preview etc.)
+//
+// "CUSTOM" sizes for game elements (like 64x64) may be additionally created;
+// all "OTHER" image sizes are stored if different from all other bitmap sizes,
+// which may be used "as is" by global animations (as the "standard" size used
+// normally may be wrong due to being scaled up or down to a different size if
+// the same image contains game elements in a non-standard size)
+