Slick2d collision detection with Tiles using rectangles

Question

i'm quite stuck. Before I do anything, heres the code:

 if(inAir&&!falling&&!jumping){

        if(py<600){
              if (!(isBlocked(xminusd, py) || isBlocked(xminus, py + 32 - 1))) {
             falling=true;
        }else{
            py-=2;
            inAir=false;
        }
        }
    }
    for(int g = 0;g<Map.r.size();g++){
    if(rect.intersects(Map.r.get(g))||Map.r.get(g).contains(rect)||rect.contains(Map.r.get(g))||Map.r.get(g).intersects(rect)){
        System.out.println("Intersecting!");
        inAir= false;
        hasjumped=false;
        onPlat = true;
        falling = false;

        jumping = false;
        py-=4;
        break;

    }else{

        onPlat = false;
        if(inAir==false&&!onPlat){
        inAir = true;
        onPlat = false;
        }
    }
    }

Now the problem is, i'm trying to make collision detection with a certain type of tile, by creating rectangles for each tile, and if the player collides with it it stops all movement.(falling wise at least). But i've run into a problem. I've used an array list, to create all my rectangles, and i'm using a for loop to check each rectangle. Problem is, if it checks a rectangle and i'm not colliding with that rectangle currently, it immidiatly starts falling, then resetting, because it finds the rectangle i'm colliding with. The problem is im using a for loop to cycle through each rectangle... I'm really stuck on how to do collision detection with platform tiles. Anyone have any help to provide? Please be descriptive.

thermite thermite · Accepted Answer · 2013-11-10T19:51:52

It doesn't look like it matters which rectangle you are colliding with so try abstracting by making a function that returns true or false if it is colliding with any block and put that in your else if statement. that way if you are still colliding it wont start falling while cycling through the rest of your blocks

Something like

...
if(colliding())
{
    //stop falling
}
else
{
    //start falling
}
.... 

boolean colliding(){
    for(int g = 0;g<Map.r.size();g++){
        //check for collision if true return true
    }
    return false;
}

EDIT:

The reason this works is because as you are going through the for loop it keeps the object falling while it determines that it should stop. By moving the falling logic away from the collision logic we can determine if it is colliding and then take the appropriate action.

Slick2d collision detection with Tiles using rectangles

1 Answers