Creating hollow circles

So if I want to create a circle solid, I'd just use this:

PHP:

function src(Position $centre, $radius, Block $block)
{
    for ($x = $centre->x - $radius; $x <= $centre->x + $radius; $x++) {
        // same for z
        if ($centre->distance(new Vector3($x, $centre->y, $z)) <= $radius) {
            // set block
        }
    }
}



But what about hollow spheres?

I ll try to figure it out too !

What about running it twice and subtracting radius by one and put block of air?

Yes, but consider the thickness variation for larger circles. (Rounding to integer will create holes)

@PEMapModder
http://forums.pocketmine.net/plugins/drawstuff.410/
function fncDrawSphere (line 548)
* lines 580-590 (forget about Y)

maybe you can learn something about that little piece of code from BC Yorkie

Idk. I never tested. But something in my brain is itchy about blank spots.

For a world editor, a fine solution is user-defined thickness. But I want to generate spleef arena walls with it, so there I'd something different.

https://github.com/PEMapModder/PEMa...rc/pemapmodder/utils/spaces/CylinderSpace.php

If you want a vertical circle you could use this:

PHP:

function circle(Position $pos, $radius, Block $block) {
    for($a = 0; $a <= 360; $a++) {
        $x = $pos->x + (cos(deg2rad($a)) * $radius);
        $y = $pos->y + (sin(deg2rad($a)) * $radius);
        $z = $pos->z;
        // set block here
    }
}

Not sure about horizontal though.

Switch y for z for horizontal !

It's hard to explain it, but I'll try.
First you generate one circle with the radius that you want the hollow sphere to have and store it into the memory.
Then you generate and draw radius amount of circles with a radius equal to the hight of the sphere minus the y value of the first generated circle at x = number of the circle.
I'll try to make an example code.

Btw, this thread content most of active developers plugin i imagine the dream team !!!

Ok I made a hollow sphere generator, it uses the Bresenham's circle algorithm which is one of the fastest ways to generate a circle. So this should also be one of the fastest ways to generate a hollow sphere. I couldn't test it yet, but it should work.
http://pastebin.com/j0Hr6HcC

The efficiency is too low, and gaps definitely would occur for large ones.

I always had problems with gaps in large circles. But I never knew how to fix it.

Looks very useful.

Anyway I don't think new Block($blockId) is correct.