Rust-Perlin-Noise

perlinnoise.rs

fn floor(a: float) -> float {
  let mut b = a as f64;
	b = float::floor(b);
	let c = b as float;
	return c;
}
fn permentation() -> ~[int] {
	let list = ~[151,160,137,91,90,15,131,13,201,95,96,53,194,233,7,225,140,36,
				   103,30,69,142,8,99,37,240,21,10,23,190,6,148,247,120,234,75,0,
				   26,197,62,94,252,219,203,117,35,11,32,57,177,33,88,237,149,56,
				   87,174,20,125,136,171,168,68,175,74,165,71,134,139,48,27,166,
				   77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,
				   46,245,40,244,102,143,54,65,25,63,161,1,216,80,73,209,76,132,
				   187,208,89,18,169,200,196,135,130,116,188,159,86,164,100,109,
				   198,173,186,3,64,52,217,226,250,124,123,5,202,38,147,118,126,
				   255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,223,183,
				   170,213,119,248,152,2,44,154,163,70,221,153,101,155,167,43,172,
				   9,129,22,39,253,19,98,108,110,79,113,224,232,178,185,112,104,
				   218,246,97,228,251,34,242,193,238,210,144,12,191,179,162,241,
				   81,51,145,235,249,14,239,107,49,192,214,31,181,199,106,157,184,
				   84,204,176,115,121,50,45,127,4,150,254,138,236,205,93,222,114,
				   67,29,24,72,243,141,128,195,78,66,215,61,156,180];

	return vec::concat([copy list, copy list]);
}
fn lerp(t: float, a: float,  b: float) -> float {
	return a + t * (b - a);
}
fn fade(t: float) -> float {
	return t * t * t * (t * (t * 6.0 - 15.0) + 10.0);
}
fn grad(hash: int, x: float, y: float, z: float) -> float {
	let hi = hash as int;
	let h = hi & 15;
	let u = if h < 8 { x } else { y };
	let v = if h < 4 { y } else { if h == 12 || h == 14 { x } else { z } };
	return (if h & 1 == 0 { u } else { -u }) + (if h & 2 == 0 { v } else { -v });
}
fn snoise(nx: float, ny: float, nz: float, p: ~[int]) -> float {
	let nxi = nx as int;
	let nyi = ny as int;
	let nzi = nz as int;

	let floopXi = nxi & 255;
	let floopYi = nyi & 255;
	let floopZi = nzi & 255;

	let x = floor(nx)-nx;
	let y = floor(ny)-ny;
	let z = floor(nz)-nz;

	let u = fade(x);
	let v = fade(y);
	let w = fade(z);

	let a = p[floopXi] + floopYi;
	let ai = a as int;
	let aa = p[ai] + floopZi;
	let ab = p[ai+1] + floopZi;
	let b = p[floopXi + 1] + floopYi;
	let bi = b as int;
	let ba = p[bi] + floopZi;
	let bb = p[bi + 1] + floopZi;

	let pAA = p[aa];
	let pAB = p[ab];
	let pBA = p[ba];
	let pBB = p[bb];
	let pAA1 = p[aa+1];
	let pAB1 = p[ab+1];
	let pBA1 = p[ba+1];
	let pBB1 = p[bb+1];

	let gradAA = grad(pAA, x, y, z);
	let gradBA = grad(pBA, x-1.0, y, z);
	let gradAB = grad(pAB, x, y-1.0, z);
	let gradBB = grad(pBB,x-1.0,y-1.0,z);
	let gradAA1 = grad(pAA1, x, y , z-1.0);
	let gradBA1 = grad(pBA1,x-1.0,y,z-1.0);
	let gradAB1 = grad(pAB1,x,y-1.0,z-1.0);
	let gradBB1 = grad(pBB1,x-1.0,y-1.0,z-1.0);

	return lerp(w,
		lerp(v, lerp(u, gradAA, gradBA), lerp(u, gradAB, gradBB)),
		lerp(v, lerp(u, gradAA1, gradBA1), lerp(u, gradAB1, gradBB1))
		);
}
fn main() {
	let x = 11.0;
	let y = 5.0;
	let z = 1.0;

	let max = 30;
	let min = 10;

	let seed = 0.12312313512341;
	let quality = 128.0;
	let delta = quality + seed;
	let perm = permentation();
	
	let sn = snoise((x / seed) / delta, (y / seed) / delta, (z / seed) / delta,perm);

	let sni = sn as int;

	let noise = (sni + 1) / 2 * (max - min) + min;
	
	io::println(fmt!("%?",noise));
}