Vanilla run_game_loop question

[tom]

Hey folks,

I'm trying to get my head around the run_game_loop function in V 4.2.4. It contains 3 instances of this code:

	/* Keep processing the player until they use some energy or
	 * another command is needed */
	while (player->upkeep->playing) {
		process_player();
		if (player->upkeep->energy_use)
			break;
		else
			return;
	}

Two of these instances happen before player energy is incremented by

			player->energy += turn_energy(player->state.speed);

I don't understand what cases these are covering, and how the player would still have energy.

[Nick]

It's because there are a lot of commands (looking at the inventory, inscribing, looking around, etc) that don't use energy - they're essentially UI commands rather than game commands. So the bigger loop is the ui-loop in ui-game.c:

		while (!player->is_dead && player->upkeep->playing) {
			pre_turn_refresh();
			cmd_get_hook(CTX_GAME);
			run_game_loop();
		}

If the command this gets doesn't use energy, it is still the player's turn, so they get to do stuff until a command does use energy.

[tom]

Hmmmmmm. Thanks Nick. I'm experimenting with a sil-q style 'delving' power (to replace ranger/druid mapping), that uses distance from player (sound) to do the mapping. But that has necessitated propagating the sound a bit more often than the V game loop does. I guess the right thing to do is recalculate sound if the player has actually used some energy... but that might be multiple places

[backwardsEric]

I guess the right thing to do is recalculate sound if the player has actually used some energy... but that might be multiple places

Then you might check for that in game-world.c's process_player_cleanup() which is run after handling each player command.

[Nick]

Note too that Sil has game turns (turn) and player turns (player_turn) and its way of handling when things happen is a bit different. It also uses the old style game loop from before Angband 4.0.