Forums » Help » Enemy spawner with trigger

Hey guys. The game I have been working on is coming along nicely, but I have been thinking about using an enemy spawner entity in weltmeister to spawn my enemies instead of just placing them in weltmeister. I searched the forums for an answer, but all i could find was a thread about limiting the spawner to one entity at a time being spawned. I want to use a combination of a trigger and a enemy spawner entity that are connected with a key/value pair in weltmeister so that the player can literally "farm" enemies for items by being able to spawn a new entity after the last spawns. Here is what I have so far and I am getting no errors, but the skeleton isn't spawning at all.

trigger

ig.module(
	'game.entities.trigger'
)
.requires(
	'impact.entity'
)
.defines(function(){

EntityTrigger = ig.Entity.extend({
	size: {x: 16, y: 16},
	
	_wmScalable: true,
	_wmDrawBox: true,
	_wmBoxColor: 'rgba(196, 255, 0, 0.7)',
	
	target: null,
	wait: -1,
	waitTimer: null,
	canFire: true,
	
	type: ig.Entity.TYPE.NONE,
	checkAgainst: ig.Entity.TYPE.A,
	collides: ig.Entity.COLLIDES.NEVER,
	
	
	init: function( x, y, settings ) {
		if( settings.checks ) {
			this.checkAgainst = ig.Entity.TYPE[settings.checks.toUpperCase()] || ig.Entity.TYPE.A;
			delete settings.check;
		}
		
		this.parent( x, y, settings );
		this.waitTimer = new ig.Timer();
	},
	
	
	check: function( other ) {
		if( this.canFire && this.waitTimer.delta() >= 0 ) {
			if( typeof(this.target) == 'object' ) {
				for( var t in this.target ) {
					var ent = ig.game.getEntityByName( this.target[t] );
					if( ent && typeof(ent.triggeredBy) == 'function' ) {
						ent.triggeredBy( other, this );
					}
				}
			}
			
			if( this.wait == -1 ) {
				this.canFire = false;
			}
			else {
				this.waitTimer.set( this.wait );
			}
		}
	},
	
	
	update: function(){}
});

});

enemy-spawner

ig.module(
    'game.entities.enemy-spawner'
)
.requires(
    'impact.entity',
    'game.entities.skeleton'
)
.defines(function () {

    EntityEnemySpawner = ig.Entity.extend({

        _wmScalable: true,
        _wmDrawBox: true,
        _wmBoxColor: 'rgba(255, 170, 66, 0.7)',

        type: ig.Entity.TYPE.NONE,
        collides: ig.Entity.COLLIDES.NEVER,

        enemy: null,

        triggeredBy: function (other) {
            if (!this.enemy || this.enemy._killed) {
                this.enemy = ig.game.spawnEntity(EntitySkeleton,x,y);
            }
        }

    });

});

Did you properly connect those two entities? WM should draw a line between them.

Is the triggers check() method is called at all? Is the spawner's triggeredBy() method called? Try putting some console.log() messages in there to check.

They are properly connected in WM. I have a line connecting them. Also, when the player passes through the trigger area I get a "hitch" in the game like it was trying to load something. It almost feels like lag, but not.

I will try a console.log and check those methods. Thank you dominic.

I got it.

this.enemy = ig.game.spawnEntity(EntitySkeleton,x,y);

should be:

this.enemy = ig.game.spawnEntity(EntitySkeleton,this.pos.x,this.pos.y);


EDIT: Well I got the initial spawn working, but after the enemy dies I cannot spawn a new one by walking through the trigger again.

Did your trigger spawner disable itself?

There is a 'wait' property on EntityTrigger that sets how long the trigger will delay after triggering before enabling itself again. By default, it is set to '-1' which causes the trigger to disable itself indefinitely. If you set it to a number > -1, it will wait that long in seconds and then re-enable itself.