diff --git a/src/test/bench/noise.rs b/src/test/bench/noise.rs index e9e59924acc..42918ae5aa0 100644 --- a/src/test/bench/noise.rs +++ b/src/test/bench/noise.rs @@ -8,128 +8,112 @@ // option. This file may not be copied, modified, or distributed // except according to those terms. -// Perlin noise benchmark from https://gist.github.com/1170424 +// Multi-language Perlin noise benchmark. +// See https://github.com/nsf/pnoise for timings and alternative implementations. -use std::f64; -use std::rand::Rng; -use std::rand; +use std::f32::consts::PI; +use std::rand::{Rng, StdRng}; struct Vec2 { x: f32, y: f32, } -#[inline(always)] fn lerp(a: f32, b: f32, v: f32) -> f32 { a * (1.0 - v) + b * v } -#[inline(always)] fn smooth(v: f32) -> f32 { v * v * (3.0 - 2.0 * v) } -fn random_gradient(r: &mut R) -> Vec2 { - let v = 2.0 * f64::consts::PI * r.gen(); - Vec2 { - x: v.cos() as f32, - y: v.sin() as f32, - } +fn random_gradient(r: &mut R) -> Vec2 { + let v = PI * 2.0 * r.gen(); + Vec2 { x: v.cos(), y: v.sin() } } fn gradient(orig: Vec2, grad: Vec2, p: Vec2) -> f32 { - let sp = Vec2 {x: p.x - orig.x, y: p.y - orig.y}; - grad.x * sp.x + grad.y * sp.y + (p.x - orig.x) * grad.x + (p.y - orig.y) * grad.y } struct Noise2DContext { rgradients: [Vec2, ..256], - permutations: [int, ..256], + permutations: [i32, ..256], } impl Noise2DContext { - pub fn new() -> Noise2DContext { - let mut r = rand::rng(); - let mut rgradients = [ Vec2 { x: 0.0, y: 0.0 }, ..256 ]; - for i in range(0, 256) { - rgradients[i] = random_gradient(&mut r); - } - let mut permutations = [ 0, ..256 ]; - for i in range(0, 256) { - permutations[i] = i; - } - r.shuffle_mut(permutations); + fn new() -> Noise2DContext { + let mut rng = StdRng::new(); - Noise2DContext { - rgradients: rgradients, - permutations: permutations, + let mut rgradients = [Vec2 { x: 0.0, y: 0.0 }, ..256]; + for x in rgradients.mut_iter() { + *x = random_gradient(&mut rng); } + + let mut permutations = [0i32, ..256]; + for (i, x) in permutations.mut_iter().enumerate() { + *x = i as i32; + } + rng.shuffle_mut(permutations); + + Noise2DContext { rgradients: rgradients, permutations: permutations } } - #[inline(always)] - pub fn get_gradient(&self, x: int, y: int) -> Vec2 { + fn get_gradient(&self, x: i32, y: i32) -> Vec2 { let idx = self.permutations[x & 255] + self.permutations[y & 255]; self.rgradients[idx & 255] } - #[inline] - pub fn get_gradients(&self, - gradients: &mut [Vec2, ..4], - origins: &mut [Vec2, ..4], - x: f32, - y: f32) { + fn get_gradients(&self, x: f32, y: f32) -> ([Vec2, ..4], [Vec2, ..4]) { let x0f = x.floor(); let y0f = y.floor(); - let x0 = x0f as int; - let y0 = y0f as int; + let x1f = x0f + 1.0; + let y1f = y0f + 1.0; + + let x0 = x0f as i32; + let y0 = y0f as i32; let x1 = x0 + 1; let y1 = y0 + 1; - gradients[0] = self.get_gradient(x0, y0); - gradients[1] = self.get_gradient(x1, y0); - gradients[2] = self.get_gradient(x0, y1); - gradients[3] = self.get_gradient(x1, y1); - - origins[0] = Vec2 {x: x0f + 0.0, y: y0f + 0.0}; - origins[1] = Vec2 {x: x0f + 1.0, y: y0f + 0.0}; - origins[2] = Vec2 {x: x0f + 0.0, y: y0f + 1.0}; - origins[3] = Vec2 {x: x0f + 1.0, y: y0f + 1.0}; + ([self.get_gradient(x0, y0), self.get_gradient(x1, y0), + self.get_gradient(x0, y1), self.get_gradient(x1, y1)], + [Vec2 { x: x0f, y: y0f }, Vec2 { x: x1f, y: y0f }, + Vec2 { x: x0f, y: y1f }, Vec2 { x: x1f, y: y1f }]) } - #[inline] - pub fn get(&self, x: f32, y: f32) -> f32 { + fn get(&self, x: f32, y: f32) -> f32 { let p = Vec2 {x: x, y: y}; - let mut gradients = [ Vec2 { x: 0.0, y: 0.0 }, ..4 ]; - let mut origins = [ Vec2 { x: 0.0, y: 0.0 }, ..4 ]; - self.get_gradients(&mut gradients, &mut origins, x, y); + let (gradients, origins) = self.get_gradients(x, y); + let v0 = gradient(origins[0], gradients[0], p); let v1 = gradient(origins[1], gradients[1], p); let v2 = gradient(origins[2], gradients[2], p); let v3 = gradient(origins[3], gradients[3], p); + let fx = smooth(x - origins[0].x); let vx0 = lerp(v0, v1, fx); let vx1 = lerp(v2, v3, fx); let fy = smooth(y - origins[0].y); + lerp(vx0, vx1, fy) } } fn main() { - let symbols = [" ", "░", "▒", "▓", "█", "█"]; + let symbols = [' ', '░', '▒', '▓', '█', '█']; let mut pixels = [0f32, ..256*256]; - let n2d = ~Noise2DContext::new(); - for _ in range(0, 100u) { + let n2d = Noise2DContext::new(); + + for _ in range(0, 100) { for y in range(0, 256) { for x in range(0, 256) { - let v = n2d.get( - x as f32 * 0.1f32, - y as f32 * 0.1f32 - ) * 0.5f32 + 0.5f32; - pixels[y*256+x] = v; - }; - }; - }; + let v = n2d.get(x as f32 * 0.1, y as f32 * 0.1); + pixels[y*256+x] = v * 0.5 + 0.5; + } + } + } for y in range(0, 256) { for x in range(0, 256) { - print!("{}", symbols[(pixels[y*256+x] / 0.2f32) as int]); + let idx = (pixels[y*256+x] / 0.2) as uint; + print!("{:c}", symbols[idx]); } - println!(""); + print!("\n"); } }