Lua, game state and game loop

Question

1. Call main.lua script at each game loop iteration - is it good or bad design? How does it affect on the performance (relatively)?

2. Maintain game state fro

Answer 1

1. You probably don't want to execute the entire Lua script on every frame iteration, because any sufficiently complex game will have multiple game objects with their own behaviors. In other words, the advantages of Lua are lost unless you have multiple tiny scripts that handle a specific part of the behavior of a larger game. You can use the lua_call function to call any appropriate lua routine in your script, not just the entire file.

2. There's no ideal answer here, but the vast majority of your game state is traditionally stored in the game engine (i.e. C++). You reveal to Lua just enough for Lua to do the decision making that you've assigned to Lua.

You need to consider which language is appropriate for which behaviors. Lua is useful for high level controls and decisions, and C++ is useful for performance oriented code. Lua is particularly useful for the parts of your game that you need to tweak without recompiling. All magic constants and variables could go into Lua, for example. Don't try to shoehorn Lua where it does not belong, i.e. graphics or audio rendering.