Included in any Twigz Level file (".lvl") are the level images and image masks. The level images make up the background on which the Ego will walk. The image masks add a three-dimensional feel to the level, creating a virtual z-axis, so the actor will "walk behind" certain parts of the map.

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The above three images were combined to create the room image.

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The above three images were combined to create the room mask image.

The above image is the finished product for a room image & mask.

All non-masked areas get color index 50 (deep green in background). All areas that lie on z-plane 1 get colored with index 1 (dark blue), all areas that fall on z-plane 2 get colored with index 2 (light blue), and so on. When an actor room is created and the walking boxes are drawn, the z-index number of that box must be set. The Ego will walk behind all areas in the mask image that are colored with that z-index color and anything less. So if the Ego is in a walking box with a z-index of 3, the Ego will walk behind all areas colored with color index 3 and less.

Note: All colors must conform to the GLOBAL PALETTE