jsx
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a faster, safer, easier JavaScript
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JavaScript
// the origina AOBench
// http://code.google.com/p/aobench/
"use strict";
var NSUBSAMPLES = 2
var NAO_SAMPLES = 8
function vec(x, y, z)
{
this.x = x;
this.y = y;
this.z = z;
}
function vadd(a, b)
{
return new vec(a.x + b.x, a.y + b.y, a.z + b.z);
}
function vsub(a, b)
{
return new vec(a.x - b.x, a.y - b.y, a.z - b.z);
}
function vcross(a, b)
{
return new vec(a.y * b.z - a.z * b.y,
a.z * b.x - a.x * b.z,
a.x * b.y - a.y * b.x);
}
function vdot(a, b)
{
return (a.x * b.x + a.y * b.y + a.z * b.z);
}
function vlength(a)
{
return Math.sqrt(a.x * a.x + a.y * a.y + a.z * a.z);
}
function vnormalize(a)
{
var len = vlength(a);
var v = new vec(a.x, a.y, a.z);
if (Math.abs(len) > 1.0e-17) {
v.x /= len;
v.y /= len;
v.z /= len;
}
return v;
}
function Sphere(center, radius)
{
this.center = center;
this.radius = radius;
this.intersect = function (ray, isect) {
// rs = ray.org - sphere.center
var rs = vsub(ray.org, this.center);
var B = vdot(rs, ray.dir);
var C = vdot(rs, rs) - (this.radius * this.radius);
var D = B * B - C;
if (D > 0.0) {
var t = -B - Math.sqrt(D);
if ( (t > 0.0) && (t < isect.t) ) {
isect.t = t;
isect.hit = true;
isect.p = new vec(ray.org.x + ray.dir.x * t,
ray.org.y + ray.dir.y * t,
ray.org.z + ray.dir.z * t);
// calculate normal.
var n = vsub(isect.p, this.center);
isect.n = vnormalize(n);
}
}
}
}
function Plane(p, n)
{
this.p = p;
this.n = n;
this.intersect = function (ray, isect) {
var d = -vdot(this.p, this.n);
var v = vdot(ray.dir, this.n);
if (Math.abs(v) < 1.0e-17) return; // no hit
var t = -(vdot(ray.org, n) + d) / v;
if ( (t > 0.0) && (t < isect.t) ) {
isect.hit = true;
isect.t = t;
isect.n = this.n;
isect.p = new vec( ray.org.x + t * ray.dir.x,
ray.org.y + t * ray.dir.y,
ray.org.z + t * ray.dir.z );
}
}
}
function Ray(org, dir)
{
this.org = org;
this.dir = dir;
}
function Isect()
{
this.t = 1000000.0; // far away
this.hit = false;
this.p = new vec(0.0, 0.0, 0.0)
this.n = new vec(0.0, 0.0, 0.0)
}
function clamp(f)
{
var i = f * 255.5;
if (i > 255.0) i = 255.0;
if (i < 0.0) i = 0.0;
return Math.round(i)
}
function orthoBasis(basis, n)
{
basis[2] = new vec(n.x, n.y, n.z)
basis[1] = new vec(0.0, 0.0, 0.0)
if ((n.x < 0.6) && (n.x > -0.6)) {
basis[1].x = 1.0;
} else if ((n.y < 0.6) && (n.y > -0.6)) {
basis[1].y = 1.0;
} else if ((n.z < 0.6) && (n.z > -0.6)) {
basis[1].z = 1.0;
} else {
basis[1].x = 1.0;
}
basis[0] = vcross(basis[1], basis[2]);
basis[0] = vnormalize(basis[0]);
basis[1] = vcross(basis[2], basis[0]);
basis[1] = vnormalize(basis[1]);
}
var spheres;
var plane;
function init_scene()
{
spheres = new Array(3);
spheres[0] = new Sphere(new vec(-2.0, 0.0, -3.5), 0.5);
spheres[1] = new Sphere(new vec(-0.5, 0.0, -3.0), 0.5);
spheres[2] = new Sphere(new vec(1.0, 0.0, -2.2), 0.5);
plane = new Plane(new vec(0.0, -0.5, 0.0), new vec(0.0, 1.0, 0.0));
}
function ambient_occlusion(isect)
{
var basis = new Array(3);
orthoBasis(basis, isect.n);
var ntheta = NAO_SAMPLES;
var nphi = NAO_SAMPLES;
var eps = 0.0001;
var occlusion = 0.0;
var p = new vec(isect.p.x + eps * isect.n.x,
isect.p.y + eps * isect.n.y,
isect.p.z + eps * isect.n.z);
for (var j = 0; j < nphi; j++) {
for (var i = 0; i < ntheta; i++) {
var r = Math.random();
var phi = 2.0 * Math.PI * Math.random();
var x = Math.cos(phi) * Math.sqrt(1.0 - r);
var y = Math.sin(phi) * Math.sqrt(1.0 - r);
var z = Math.sqrt(r);
// local -> global
var rx = x * basis[0].x + y * basis[1].x + z * basis[2].x;
var ry = x * basis[0].y + y * basis[1].y + z * basis[2].y;
var rz = x * basis[0].z + y * basis[1].z + z * basis[2].z;
var raydir = new vec(rx, ry, rz);
var ray = new Ray(p, raydir);
var occIsect = new Isect();
spheres[0].intersect(ray, occIsect);
spheres[1].intersect(ray, occIsect);
spheres[2].intersect(ray, occIsect);
plane.intersect(ray, occIsect);
if (occIsect.hit) occlusion += 1.0;
}
}
// [0.0, 1.0]
occlusion = (ntheta * nphi - occlusion) / (ntheta * nphi);
return new vec(occlusion, occlusion, occlusion);
}
function render(fill, w, h, nsubsamples)
{
for (var y = 0; y < h; y++) {
for (var x = 0; x < w; x++) {
var rad = new vec(0.0, 0.0, 0.0);
// subsampling
for (var v = 0; v < nsubsamples; v++) {
for (var u = 0; u < nsubsamples; u++) {
var px = (x + (u / nsubsamples) - (w / 2.0))/(w / 2.0);
var py = -(y + (v / nsubsamples) - (h / 2.0))/(h / 2.0);
var eye = vnormalize(new vec(px, py, -1.0));
var ray = new Ray(new vec(0.0, 0.0, 0.0), eye);
var isect = new Isect();
spheres[0].intersect(ray, isect);
spheres[1].intersect(ray, isect);
spheres[2].intersect(ray, isect);
plane.intersect(ray, isect);
if (isect.hit) {
var col = ambient_occlusion(isect);
rad.x += col.x;
rad.y += col.y;
rad.z += col.z;
}
}
}
var r = clamp(rad.x / (nsubsamples * nsubsamples));
var g = clamp(rad.y / (nsubsamples * nsubsamples));
var b = clamp(rad.z / (nsubsamples * nsubsamples));
// use fill rect
fill(x, y, r, g, b);
}
}
}
if (typeof window !== "undefined") {
window.onload = function aobench_start()
{
var canvas = document.getElementById("world");
var ctx = canvas.getContext("2d");
var start = Date.now();
init_scene();
render(function (x, y, r, g, b) {
ctx.fillStyle = "rgb(" + r + "," + g + "," + b + ")";
ctx.fillRect (x, y, 1, 1);
}, canvas.width, canvas.height, 1)
var elapsed = Date.now() - start;
document.getElementById("status").innerHTML = "Time = " + elapsed + "[ms]";
//img = ctx.getImageData(10, 10, 50, 50)
//document.write(img.data[41]);
//ret = ctx.putImagedata(img, 10, 10);
//print(ret);
}
}
else {
exports.render = render;
}