[Mosquito]

Outside of the Quake engine, the half-life engine, and the Lithtech engine, 3rd person shooter engines have pretty much been done to death. Why spend the time, money and resources to write something when 90% of the work has already been done. That's the basis if modern software development. Take an existing package, modify it to fit your needs, and plug it in. Even though many companies use the quake engine, that doesn't nean that they use it as is. You change the source to get it to do what you want, recompile and boom working engine for a 10th the cost. Pass the savings on to model development and graphic design.
Everything we build now (cars, trucks, buildings, computers, etc...) is based on previous research and development.

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