The game loop ============= Game loops are the kernels of games that drive the whole thing. LÖVE defines the low-level loop of updating the state, rendering, processing input, etc., but a roguelike engine needs a turn-based loop that waits for the player to do something. In prism, we've implemented the game loop as a Lua `coroutine `_. The following diagram describes the main loop. .. raw:: html

The core game loop

:lua:class:`Level` defines the loop, and :lua:class:`LevelState` holds the coroutine and determines when to continue it. If no :lua:class:`Controller` yields a :lua:class:`Decision` the loop will run indefinitely, forcing you to catch when there are no player controlled actors left in the level. What actually happens on an actor's turn is defined in :lua:data:`prism.turn`. By default, it calls the :lua:class:`Controller` and performs the action returned: .. code-block:: lua local action = controller:act(level, actor) -- we make sure we got an action back from the controller for sanity's sake assert(action, "Actor " .. actor:getName() .. " returned nil from act()") level:perform(action) If actors can perform multiple actions, you would need to override this.