How to work with line of sight on tilemapLayer

[marvster]

Like the line of sight demo on game mechanicexplorer (http://gamemechanicexplorer.com/#raycasting-1), I'd like use ray casting for enemy detection and movement (chasing), but on a big tilemap, with a specific layer holding the collision information for certain tiles.

 

My questions are:

- How can I get this ray cast demo work with tilemapLayer? I looked up the docs, but could figure it out.

- How can I assure perfomance, as the whole map would consist easily 100-200 objects in general which need to be ray casted, even just a few are in a relevant range where line of sight detection makes sense?

 

[kass]

theres actually a official tilemap raycast example

[marvster]

Thanks alot kass,

 

that was exactly what I wanted. Unfortunately my fear come true, as it seems, that all objects will be checked, even those not shown on the screen:

 

I've tried to use the visible property of the sprite, but this seems not to be functional.

this.enemyGroup.forEachExists(function (enemy) {            this.game.physics.arcade.collide(this.player, enemy);            var ray = new Phaser.Line(enemy.x, enemy.y, this.player.x, this.player.y);            var tileHits = this.map.layer3.getRayCastTiles(ray, 4, true, false);            if (tileHits.length > 0 && enemy.visible) {                enemy.tint = 0xffffff;                enemy.seePlayer = false;            } else {                enemy.tint = 0xffaaaa;                enemy.seePlayer = true;            }        }, this);

Any Idea?

[marvster]

Found a solution, even it seems not to work on every Browser:

this.enemyGroup.forEach(function (enemy) {            if (enemy.inCamera) {                this.game.physics.arcade.collide(this.player, enemy);                var ray = new Phaser.Line(enemy.x, enemy.y, this.player.x, this.player.y);                var tileHits = this.map.layer3.getRayCastTiles(ray, 4, true, false);                if (tileHits.length > 0 && enemy.inCamera) {                    enemy.tint = 0xffffff;                    enemy.seePlayer = false;                } else {                    enemy.tint = 0xffaaaa;                    enemy.seePlayer = true;                }            }        }, this);

With a tilemap 1440x1440 and 100 objects, the frame rate was on Chrome between 50-60fps, in Firefox under 20fps (which broke collision detection) and in IE constant 60fps. It seems that Firefox will handle some stuff in a different way.