Question

So i have sprites that are should be un-walkable for my character.

The problem is im not sure how to do this.

Here is what i am trying. I am having the sprites added to a Linked List when they are loaded from the level.

Then i iterate through the list to detect if the character is colliding with any of the unwalkable sprites/tiles.

I do this on the engines update thread which runs about every second.

Here is how i am doing this:

mScene.registerUpdateHandler(new IUpdateHandler(){

        @Override
        public void onUpdate(float pSecondsElapsed) {


            Iterator<Sprite> wall_collision = unwalkable_Sprites.iterator();

            while(wall_collision.hasNext()){
                Sprite sprite = wall_collision.next();

                if(character_sprite.collidesWith(sprite)){


                }
            }

        }

        @Override
        public void reset() {
            // TODO Auto-generated method stub

        }

    });

So the question is how do i position the character when it collides with the unwalkable tile so the character doesnt even cross over into the tile..To the user it should seem like a boundary.

Does anyone have any suggestions or know how i can do this?

Answer 1

Look into this example

use the same code for you un-walkable tiles as “ground” in example. You should use static bodies:

this.mPhysicsWorld = new PhysicsWorld(new Vector2(0, SensorManager.GRAVITY_EARTH), false);
final FixtureDef wallFixtureDef = PhysicsFactory.createFixtureDef(0, 0.5f, 0.5f);

Here you can use Shape as in example or for example Sprite

//final Shape yourTile = new Rectangle(0, CAMERA_HEIGHT - 2, CAMERA_WIDTH, 2);
Sprite yourTile = new Sprite(...);
PhysicsFactory.createBoxBody(this.mPhysicsWorld, yourTile, BodyType.StaticBody, wallFixtureDef);

Here you can find box2dExtension for AndEngine (it need for using Bodies)

Sorry for my English 🙂 Hope this will help you.

P.S. and you don’t need to check collisions for this issue anymore.