one physics body - several sensors - how to get sensors to set variables

[valueerror]

1 collision body 4 sensors for top/left/right/down 

 

i want the sensor hovering above the player to set object_above = true; and the sensor to the right of the player to set object_right=true;  and so on..  

 

is this possible? and if so - how?

 

i thought maybe i could set onBeginContact events to the sensors individually or somehow find out which sensor reported the collision ??!

 

thx in advance    

[neoRiley]

I would also like to know the answer to this

 

I was expecting to be able to check the body that was passed in the event but I can't seem to match anything up that says "you hit the ice sensor" 

[george]

Hey,

it's far too late so it's for the moment only a gist in coffee script I can give you. But this is the core of my collision event system and helps me managing all of my collision events. The base principals: Focus on one object that collides with many others (player centric view). It's like on-to-many. So you always have on constant in your collisions. That's true for most games with a player or something else as the enter of the game. This view allows you to create a listener specific for collision of other objects with this main object. The rest is saving and finding the correct objects during a collision with the main object.

 

Gist with three JS classes. Try to convert it to JS if you are not comfortable to read coffee script.

https://gist.github.com/georgiee/7758583691d33a2c1af1

 

Usage:

Do not copy & past those. It's only example code I never tested.

//create a sprite & a p2 body with shapesball = game.add.sprite(0,0,'ball')myCircle = ball.body.addCircle(20)//CollideableEntity is a helper class so you can reference you sprite from your shape collision later.//You can also pass an array of shapes and of course you can create multiple//instances of this CollideableEntity with the same sprite but with different p2 shapes.ballCollisionEntity = new PinballGame.Core.CollideableEntity(ball, myCircle)//create the contact listeners. This one focus on the job of looking for ALL collision ONLY with the ball (through myCircle)//you will later register all those things that you're interested in to collide with the ball.ballCollisions = new PinballGame.Core.EntityContactListener(game, ballCollisionEntity)//Now register all those things you want to get notified then they collide with the ball.//create another thingythingy = game.add.sprite(0,0,'thingy')thingyShape1 = thingy.body.addCircle(20)thingyShape2 = thingy.body.addCircle(20)thingyShape3 = thingy.body.addCircle(20)thingyCollisionEntity = new PinballGame.Core.CollideableEntity(thingy, [thingyShape1,thingyShape2])@ballCollision.with(thingyCollisionEntity, handleEntityContact, handleEntityEndContact)//you could go on and register other things. My current class manages the collision detection of 50 objects with a ball and triggers a hit on the detected sprite.handleEntityContact: function(collisionEntity, contact){  entity = collisionEntity.getEntity()  if(entity === thingy){    console.log('thingy was hit!')  }}

@valueerror

To retrieve a single shape easily look at that post from neoRiley  (we are the gang of p2 ) http://www.html5gamedevs.com/topic/6054-collider-used-as-a-trigger/#entry36596

 

In this thread he posted an example of using the FixtureList class you might not know yet! I thought this was the core of your question.

 

Regards George

[george]

Ah and by the way for easy checks:

 

A contact always contains among other the following properties:

contact.bodyAcontact.bodyBcontact.shapeAcontact.shapeB

So retrieving a body or shape is always possible when you know the counterpart (shapeA belongs to bodyA, shapeB belongs to bodyB)

[valueerror]

thank you very much george - i guess this is the easiest answer to that question..    so every sensor gets a reference 

    playersensor_up = player.body.addRectangle(10,4,0,-25);    playersensor_up.sensor=true;    playersensor_down = player.body.addRectangle(10,4,0,25);    playersensor_down.sensor=true;

and then i can find out which sensor reports the collision by  

player.body.onBeginContact.add(myfunction,this);

and then do whatever is necessary  (for example)

function myfunction(bodyA,shapeA,shapeB,contactEquation){    if (shapeA == playersensor_up){ console.log('up'); }} 

[neoRiley]

I would also like to know the answer to this

 

I was expecting to be able to check the body that was passed in the event but I can't seem to match anything up that says "you hit the ice sensor" 

 

I was an idiot and have relied too much on decent code editors that have nice intellisense / autocomplete for learning api's   I hadn't realized the full signature of the collision arguments included what was being hit.

 

Level.prototype.enterCollisionHandler = function(body, shape_0, shape_1) {     if( shape_1.sensor && shape_1.id === this.ice[0].id )     {        console.log("HIT ICE");    }    else this.collisionManager.addCollision(body);};

 

Shape_1 is what you've hit.