import "allocator/arena"; // From The Computer Language Benchmarks Game // http://benchmarksgame.alioth.debian.org type float = f64; // interchangeable f32/f64 for testing const SOLAR_MASS = (4.0 * Math.PI * Math.PI); const DAYS_PER_YEAR: float = 365.24; class Body { constructor( public x: float, public y: float, public z: float, public vx: float, public vy: float, public vz: float, public mass: float ) {} offsetMomentum(px: float, py: float, pz: float): this { this.vx = -px / SOLAR_MASS; this.vy = -py / SOLAR_MASS; this.vz = -pz / SOLAR_MASS; return this; } } function Sun(): Body { return new Body( 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, SOLAR_MASS ); } function Jupiter(): Body { return new Body( 4.84143144246472090e+00, -1.16032004402742839e+00, -1.03622044471123109e-01, 1.66007664274403694e-03 * DAYS_PER_YEAR, 7.69901118419740425e-03 * DAYS_PER_YEAR, -6.90460016972063023e-05 * DAYS_PER_YEAR, 9.54791938424326609e-04 * SOLAR_MASS ); } function Saturn(): Body { return new Body( 8.34336671824457987e+00, 4.12479856412430479e+00, -4.03523417114321381e-01, -2.76742510726862411e-03 * DAYS_PER_YEAR, 4.99852801234917238e-03 * DAYS_PER_YEAR, 2.30417297573763929e-05 * DAYS_PER_YEAR, 2.85885980666130812e-04 * SOLAR_MASS ); } function Uranus(): Body { return new Body( 1.28943695621391310e+01, -1.51111514016986312e+01, -2.23307578892655734e-01, 2.96460137564761618e-03 * DAYS_PER_YEAR, 2.37847173959480950e-03 * DAYS_PER_YEAR, -2.96589568540237556e-05 * DAYS_PER_YEAR, 4.36624404335156298e-05 * SOLAR_MASS ); } function Neptune(): Body { return new Body( 1.53796971148509165e+01, -2.59193146099879641e+01, 1.79258772950371181e-01, 2.68067772490389322e-03 * DAYS_PER_YEAR, 1.62824170038242295e-03 * DAYS_PER_YEAR, -9.51592254519715870e-05 * DAYS_PER_YEAR, 5.15138902046611451e-05 * SOLAR_MASS ); } class NBodySystem { constructor(public bodies: Body[]) { var px: float = 0.0; var py: float = 0.0; var pz: float = 0.0; var size = bodies.length; for (let i = 0; i < size; ++i) { let b = unchecked(bodies[i]); let m = b.mass; px += b.vx * m; py += b.vy * m; pz += b.vz * m; } bodies[0].offsetMomentum(px, py, pz); } advance(dt: float): void { var bodies = this.bodies; var size: u32 = bodies.length; // var buffer = changetype(bodies.buffer_); for (let i: u32 = 0; i < size; ++i) { let bodyi = unchecked(bodies[i]); // let bodyi = load(buffer + i * sizeof(), 8); let ix = bodyi.x; let iy = bodyi.y; let iz = bodyi.z; let bivx = bodyi.vx; let bivy = bodyi.vy; let bivz = bodyi.vz; let bodyim = bodyi.mass; for (let j: u32 = i + 1; j < size; ++j) { let bodyj = unchecked(bodies[j]); // let bodyj = load(buffer + j * sizeof(), 8); let dx = ix - bodyj.x; let dy = iy - bodyj.y; let dz = iz - bodyj.z; let distanceSq = dx * dx + dy * dy + dz * dz; let distance = Math.sqrt(distanceSq); let mag = dt / (distanceSq * distance); let bim = bodyim * mag; let bjm = bodyj.mass * mag; bivx -= dx * bjm; bivy -= dy * bjm; bivz -= dz * bjm; bodyj.vx += dx * bim; bodyj.vy += dy * bim; bodyj.vz += dz * bim; } bodyi.vx = bivx; bodyi.vy = bivy; bodyi.vz = bivz; bodyi.x += dt * bivx; bodyi.y += dt * bivy; bodyi.z += dt * bivz; } } energy(): float { var e: float = 0.0; var bodies = this.bodies; for (let i: u32 = 0, size: u32 = bodies.length; i < size; ++i) { let bodyi = unchecked(bodies[i]); let ix = bodyi.x; let iy = bodyi.y; let iz = bodyi.z; let vx = bodyi.vx; let vy = bodyi.vy; let vz = bodyi.vz; let bim = bodyi.mass; e += 0.5 * bim * (vx * vx + vy * vy + vz * vz); for (let j: u32 = i + 1; j < size; ++j) { let bodyj = unchecked(bodies[j]); let dx = ix - bodyj.x; let dy = iy - bodyj.y; let dz = iz - bodyj.z; let distance = Math.sqrt(dx * dx + dy * dy + dz * dz); e -= bim * bodyj.mass / distance; } } return e; } } var system: NBodySystem; export function init(): void { system = new NBodySystem([ Sun(), Jupiter(), Saturn(), Uranus(), Neptune() ]); } export function step(): float { system.advance(0.01); return system.energy(); } export function bench(steps: u32): void { for (let i: u32 = 0; i < steps; ++i) system.advance(0.01); }