Once subversive, mod making has gone mainstream; some game companies even give players easy-to-use tools. Here's how Jordan Edelson, whose nom de guerre is Master X, turned a character from Half-Life into one for his mod.
1. Meet Gordon
An original Half-Life character.
2. Extract the Essentials
Using Half-Life's software development kit (SDK), Master X and his team extract the file containing Gordon's skeleton and form.
3. Plastic Surgery
Using free MilkShake 3D software, they manipulate the wire-mesh frame that represents Gordon's exterior, bulking him up and adding twin shields (top left of image 3). Next they create a surface, or "skin," for the new character (front torso is shown at bottom right of image 3).
4. New Moves
The SDK provides 77 basic actions, or animations, for Gordon. Master X and his team create 139 more, including unique karate moves. For each new animation they must make dozens of frames like the one shown at right. The frames are then combined by an SDK tool.
5. Meet Yuku
Using the C++ computer language, the team loads the new character and all his movements into their modification of Half-Life, called Xmod.
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