Title says it all.

 

how can i detect if there is an entity in front of a my custom Block?

Either a: use the onRandomTick (sp?) method in the block, take the passed in corrdinates, and pull an entity list from the world for an AABB near the block.

 

or b:  use a tile entity for the block, and do the same thing from an update tick from the tile entity.

 

brief questions get brief answers.

I'm sorry if i was a little brief in my first post but i didn't know how to explain it any further.

now what i want to do is send of a redstone signal if a entity is in front of the block.

just like tripwire but you dont have to layout a line of tripwire.

 

i hope this was a little less brief in your opinnion but i dont know how to explain it any further.

 

and can you explain a little bit more about the AABB function to detect entity's?

 

i already found this function in the pressure plate class:

public void onEntityCollidedWithBlock(World par1World, int par2, int par3, int par4, Entity par5Entity){

}

 

bu i dont know how to extend the collision box of the block.

Haven't used this code in a a few MC versions, but you want to overwrite you're block's getCollisionBoundingBoxFromPool method like so:

    /**
     * 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)
     */
    @Override
    public AxisAlignedBB getCollisionBoundingBoxFromPool(World world, int x, int y, int z)
    {
        return AxisAlignedBB.getAABBPool().addOrModifyAABBInPool(minX, minY, minZ, maxX, maxY, maxZ));
    }

With minX, minY, minZ, maxX, maxY, maxZ defining the area you want the collision hitbox to be. (A standard block would have 0.0F, 0.0F, 0.0F, 1.0F, 1.0F, 1.0F I think, and a BlockCactus's collision BB would be slightly bigger than a standard block.)

 

Then override the onEntityCollided method, and put a log statement in there to test if your bounding box is right, like so:

    /**
     * Triggered whenever an entity collides with this block (enters into the block). Args: world, x, y, z, entity
     */
    public void onEntityCollidedWithBlock(World world, int x, int y, int z, Entity entity)
    {
        System.out.println("Collision detected!");
    }