Solved Get highest block underneath player

Hey guys! Can someone show me how to get the highest block underneath a player, im working on a factions fly plugin and need to know this!

 

world.getHighestBlockAt(x, z)
or loop through all blocks starting from y = playerY - 0.5 to 0

 

Exactly- but you cannot use that Method becuase it gets the highest block no matter if it is above the player, so, I think, there SHOULD be a way to find the highest block BENEATH a y value.

 

Inside, you should subtract 1. By subtracting a double, you would have to cast each y value to an int to get the block, and you would get the same block twice.


@808sFinest
To get the highest block under a player, get the player's location and create a for loop. Each time, subtract 1 from the y. If the block at the new location is equal to something that is not air/null, then you can return that block at that location.

 

Is it that hard to cast to int?

What if you stand on a half slab: when starting with -1 it would get the block below it, not the one the player is standing on. That's why I chose -0.5

 

@FisheyLP
True, but you are using up twice the amount of memory to check for the same blocks twice just on the off chance the player is standing on a slab. If you want to check for slabs, you could also include a check for the player's current Y value as well.

 

*subtracting 0.5 from a number* *server crashes with OutOfMemoryException*
seriously that takes up not very much memory and I don't think he'll run that code 20 times a second with 5000 players online.

 

sorry guys but im lost, im new to for loops. Heres wat i got

Block b = p.getLocation().getBlock();

for(int y = p.getLocation().getBlockY(); b.getType() != Material.AIR; y--) {

 

@808sFinest
What do you do inside the for loop body (Inside the brackets)?
If you change b to the block one down (b = b.getRelative(BlockFace.DOWN) or subtract one from the location and then call getBlock() again or use World#getBlockAt(int x, int y, int z)) your code should work. Just make sure, that y is NEVER smaller than zero.

 

That's how it could work

Code:

Block b;
for (int y = p location blockY - 0.5; y > 0; y--) {
set b to block at location y
if (block is not air) break;
}

//do what you want with that block

 

do i initialize block by adding =null? sorry.. and btw im trying to tp the player on top of the block
@FisheyLP

 

@808sFinest
Yes, you do it.
You might want to put this project on hold for a/some week(s) or so, while you learn a bit more about the basics of Java though.

On the top. What is the problem? You may need to add 1 to the y coordinate.

 

Why is this tping me to the lowest y(0.5)? theres blocks at y 1-4 btw

Location pl = p.getLocation();

Location b = new Location(p.getWorld(), pl.getBlockX(), pl.getBlockY(), pl.getBlockZ());

if (cmd.getName().equalsIgnoreCase("for")) {

for (double y = p.getLocation().getBlockY() - 0.5; y > 0; y--) {

if (!b.getBlock().getType().equals(Material.AIR)) break;

p.teleport(new Location(p.getWorld(), p.getLocation().getX(), y, p.getLocation().getZ()));

p.sendMessage("" + y);

 

Code:

Player p;
Block lowestBlock = null;
Location loc = p.getLocation();
for(int y = loc.getBlockY() - 0.5; y > 0; y--) {
  lowestBlock = loc.getWorld().getBlockAt(loc.add(0, -0.5, 0));
  if(b.getType() != Material.AIR) {
    break;
  }
}

if(lowestBlock == null) {
  //block was not found
}

Should work.

 

@DoggyCode™
You messed up...
"b.getType("

b is never declared​

"lowestBlock == null"

You assign it a value at every iteration. Will never be null​

"add(0, -0.5, 0)"

Why not use subtract(d,d,d)?
​

"int y = loc.getBlockY() - 0.5; y > 0; y--"

you never use y. Check if loc.getY() > 0;
​

If you give code, working one would be nice

Now, this is also code. Bad or not? At least working (and honestly not much magic involved). The explanation in words was already given.

I would make a method for that. Optional is just there to force you to think about the result I could return null, but a NoSuchElement exception (if you choose to totally ignore everything) is much more descriptive than a NPE.

Code:

    public Optional<Block> getNextBlockUnderPlayer(Player player) {
        Location loc = player.getLocation();  // get the location of the player
        Block block; // define a block variable. Could also do that in the loop, but here it is possible too.
        while(loc.getY() >= 0) {  // as long as we are not in the void, perform the actions in the body
            loc.subtract(0, 0.5, 0);  // subtract 0.5 from the players location
            block = loc.getBlock();  // get the block at the location (now 0.5 deeper)
            if(block.getType() != Material.AIR) {  // if this is not Air ==> A block!
                return Optional.of(block);  // return the block
            }
        }
        return Optional.empty(); // nothing found (as we never returned above). Return an empty optional to indicate this.
    }

EDIT: Okay, after seeing looking at your code a bit further (use [code=java] <code> [/code] tags the next time), the code could look like magic to you. I would suggest you learning some more Java first.

 

I got it to work, but it sometimes does nothing when your an specific amount of blocks above ground. Does anybody know y and how i can fix it?

Code:

Player p = (Player) sender;

        Location ploc = p.getLocation();

        Block block;

        if (cmd.getName().equalsIgnoreCase("for")) {

            for (int y = ploc.getBlockY(); y > 0; y--) {

                ploc.subtract(0, 0.5, 0);

                block = ploc.getBlock();

                if (block.getType() != Material.AIR) {

                    p.teleport(new Location(block.getWorld(), block.getX(), block.getY() + 1, block.getZ()));

                    break;

 

@808sFinest
Well, my method seems to work. You could have a look at it. Also I would encourage you to press CTRL+A and then CTRL+SHIFT+F.

Your for is also never closed, so you miss some code.
Also look at my comments to Doggy's code, some of them apply to yours as well.

AND i realized your error. Just do what I said above (and maybe look at my code) and you will fix it automatically.

The error is a logic one.
In your for: "y > 0; y--"
In your body: "ploc.subtract(0, 0.5, 0);"
See the error? No? Well, the y coordinate will decrease by one each iteration, but the pLoc one only by 0.5. This is the error.

 

ok i got it thanks to all that helped