Back to the Bounding Boxes

[kauan99]

Hi all. After successfully implementing the 6 textured block, I decided to try the bounding boxes again. I'm reading the Block class, method by method. To be able to continue my reading and understanding of the class, I must understand these methods:

 

/**
* Adds all intersecting collision boxes to a list. (Be sure to only add boxes to the list
* if they intersect the mask.) Parameters: World, X, Y, Z, mask, list, colliding entity
*/
   public void addCollisionBoxesToList(World world, int x, int y, int z, AxisAlignedBB mask, List list, Entity collidingEntity)
   {
      AxisAlignedBB aabb = this.getCollisionBoundingBoxFromPool(world, x, y, z);
      if (aabb != null && mask.intersectsWith(aabb))
      {
         list.add(aabb);
      }
   }

   @SideOnly(Side.CLIENT)
    /**
     * Returns the bounding box of the wired rectangular prism to render.
     */
    public AxisAlignedBB getSelectedBoundingBoxFromPool(World world, int x, int y, int z)
    {
        return AxisAlignedBB.getAABBPool().getAABB(x + this.minX, y + this.minY, z + this.minZ,
						   x + this.maxX, y + this.maxY, z + this.maxZ);
    }

    /**
     * Returns a bounding box from the pool of bounding boxes (this means this box can change
     * after the pool has been cleared to be reused)
     */
    public AxisAlignedBB getCollisionBoundingBoxFromPool(World world, int x, int y, int z)
    {
        return AxisAlignedBB.getAABBPool().getAABB(x + this.minX, y + this.minY, z + this.minZ,
						   x + this.maxX, y + this.maxY, z + this.maxZ);
    }

 

Please, anyone kind enough to explain those methods to me? Pretty please?

[kauan99]

Thanks for replying! Let me see if I understand something:

 

Do I ever need to override those methods?

 

If I ever need a block that is not just a standard 1x1x1 block. Let's say I need a 2x2x2 block for some reason. Would I have to write another implementation of those methods? I ask because I'm still not sure when those methods are invoked and for what purpose. In that case of the 2x2x2 block, could I just change the values of block.maxX, block.maxY, block.maxZ instead of overriding any of those 3 methods to make my bigger block?

 

In a second hypothetical scenario, Imagine that for some reason I need a block with a complex shape (for example, imagine the shape we use to create an iron golem. Let's say for this question's sake I need to have a block shaped like that). Then, I think just changing block.maxX, block.maxY, block.maxZ wouldn't be enough. So, in this case, I'd have to override those methods.

 

Is that what those methods are for? Or I didn't understand a thing...?

[kauan99]

Hi all.

 

I just tested the first case I suggested above in a simplified manner. I added a line this.maxX += 1 to the constructor:

 

public class TwoBlock extends Block
{
public TwoBlock ()
{
	super(TwoBlockID, Material.rock);
	this.maxX += 1;
}
}

 

I correctly get a block that's 2x1x1, with it's enlargement portion being at x + 1 relative to the point where I place it. But, I can only collide with the x, y, z portion of the block. I can pass through the x + 1, y, z portion of the block, the enlargement portion. I cross it unimpeded when I move along the Y or Z axes, and I get some sort of partial collision when I move along the X axis, i.e. when I walk inside the enlargement portion towards the normal portion. If I do this, I get pushed back a little bit when I reach the normal portion.

 

How would I build this block so I would collide normally with it? I'm gessing I'd have to use those methods I asked about earlier? Thanks for any help!

[kauan99]

Sorry to do this, but I'm stuck. Anyone??