A General Guide For Mod Creation
Rock, Paper, Shotgun's Kieron Gillen has combined and updated a series of guides he wrote for getting into the development of game mods. He provides a detailed explanation of the process from concept to reality as well as a look at some of the obstacles you're likely to run into. Quoting:
"First thing is that it really is work, and should be planned as such. As I've said earlier, you really need to be aware you have to sacrifice other elements of your life to get it done. If you just rely on your free time, the Mod will fail. You may find it helpful to actually time-table periods when you can do stuff, in the same way you would book a regular evening class. If every night you put aside a limited amount of time to do work, you'll make steady progress. This is considerably healthier than the boom/bust approach which most modders will follow. But - y'know - most people on your team will move on a cycle of massive productivity followed by long fallow periods."
That depends on what you're making. Obviously a one man team can't make the next Call of Duty or whatever, making what's essentially a new, AAA grade game needs a professional development team, making the mod equivalent of a flash game doesn't take long and can feasibly be done in one's free time. I've made loads of smaller mods (for the Spring engine, modding that involves making a new set of units as well as scripting any game logic you need beyond the standard Total Annihilation hehaviour it offers) in my spare time.
And hell, modding that engine almost requires making a TC and it's not much work either.
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