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/* | |
* Copyright (C) 2007 Apple Inc. All rights reserved. | |
* | |
* Redistribution and use in source and binary forms, with or without | |
* modification, are permitted provided that the following conditions | |
* are met: | |
* 1. Redistributions of source code must retain the above copyright | |
* notice, this list of conditions and the following disclaimer. | |
* 2. Redistributions in binary form must reproduce the above copyright | |
* notice, this list of conditions and the following disclaimer in the | |
* documentation and/or other materials provided with the distribution. | |
* | |
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY | |
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR | |
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR | |
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | |
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, | |
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR | |
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY | |
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | |
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
*/ | |
function createVector(x,y,z) { | |
return new Array(x,y,z); | |
} | |
function sqrLengthVector(self) { | |
return self[0] * self[0] + self[1] * self[1] + self[2] * self[2]; | |
} | |
function lengthVector(self) { | |
return Math.sqrt(self[0] * self[0] + self[1] * self[1] + self[2] * self[2]); | |
} | |
function addVector(self, v) { | |
self[0] += v[0]; | |
self[1] += v[1]; | |
self[2] += v[2]; | |
return self; | |
} | |
function subVector(self, v) { | |
self[0] -= v[0]; | |
self[1] -= v[1]; | |
self[2] -= v[2]; | |
return self; | |
} | |
function scaleVector(self, scale) { | |
self[0] *= scale; | |
self[1] *= scale; | |
self[2] *= scale; | |
return self; | |
} | |
function normaliseVector(self) { | |
var len = Math.sqrt(self[0] * self[0] + self[1] * self[1] + self[2] * self[2]); | |
self[0] /= len; | |
self[1] /= len; | |
self[2] /= len; | |
return self; | |
} | |
function add(v1, v2) { | |
return new Array(v1[0] + v2[0], v1[1] + v2[1], v1[2] + v2[2]); | |
} | |
function sub(v1, v2) { | |
return new Array(v1[0] - v2[0], v1[1] - v2[1], v1[2] - v2[2]); | |
} | |
function scalev(v1, v2) { | |
return new Array(v1[0] * v2[0], v1[1] * v2[1], v1[2] * v2[2]); | |
} | |
function dot(v1, v2) { | |
return v1[0] * v2[0] + v1[1] * v2[1] + v1[2] * v2[2]; | |
} | |
function scale(v, scale) { | |
return [v[0] * scale, v[1] * scale, v[2] * scale]; | |
} | |
function cross(v1, v2) { | |
return [v1[1] * v2[2] - v1[2] * v2[1], | |
v1[2] * v2[0] - v1[0] * v2[2], | |
v1[0] * v2[1] - v1[1] * v2[0]]; | |
} | |
function normalise(v) { | |
var len = lengthVector(v); | |
return [v[0] / len, v[1] / len, v[2] / len]; | |
} | |
function transformMatrix(self, v) { | |
var vals = self; | |
var x = vals[0] * v[0] + vals[1] * v[1] + vals[2] * v[2] + vals[3]; | |
var y = vals[4] * v[0] + vals[5] * v[1] + vals[6] * v[2] + vals[7]; | |
var z = vals[8] * v[0] + vals[9] * v[1] + vals[10] * v[2] + vals[11]; | |
return [x, y, z]; | |
} | |
function invertMatrix(self) { | |
var temp = new Array(16); | |
var tx = -self[3]; | |
var ty = -self[7]; | |
var tz = -self[11]; | |
for (h = 0; h < 3; h++) | |
for (v = 0; v < 3; v++) | |
temp[h + v * 4] = self[v + h * 4]; | |
for (i = 0; i < 11; i++) | |
self[i] = temp[i]; | |
self[3] = tx * self[0] + ty * self[1] + tz * self[2]; | |
self[7] = tx * self[4] + ty * self[5] + tz * self[6]; | |
self[11] = tx * self[8] + ty * self[9] + tz * self[10]; | |
return self; | |
} | |
// Triangle intersection using barycentric coord method | |
function Triangle(p1, p2, p3) { | |
var edge1 = sub(p3, p1); | |
var edge2 = sub(p2, p1); | |
var normal = cross(edge1, edge2); | |
if (Math.abs(normal[0]) > Math.abs(normal[1])) | |
if (Math.abs(normal[0]) > Math.abs(normal[2])) | |
this.axis = 0; | |
else | |
this.axis = 2; | |
else | |
if (Math.abs(normal[1]) > Math.abs(normal[2])) | |
this.axis = 1; | |
else | |
this.axis = 2; | |
var u = (this.axis + 1) % 3; | |
var v = (this.axis + 2) % 3; | |
var u1 = edge1[u]; | |
var v1 = edge1[v]; | |
var u2 = edge2[u]; | |
var v2 = edge2[v]; | |
this.normal = normalise(normal); | |
this.nu = normal[u] / normal[this.axis]; | |
this.nv = normal[v] / normal[this.axis]; | |
this.nd = dot(normal, p1) / normal[this.axis]; | |
var det = u1 * v2 - v1 * u2; | |
this.eu = p1[u]; | |
this.ev = p1[v]; | |
this.nu1 = u1 / det; | |
this.nv1 = -v1 / det; | |
this.nu2 = v2 / det; | |
this.nv2 = -u2 / det; | |
this.material = [0.7, 0.7, 0.7]; | |
} | |
Triangle.prototype.intersect = function(orig, dir, near, far) { | |
var u = (this.axis + 1) % 3; | |
var v = (this.axis + 2) % 3; | |
var d = dir[this.axis] + this.nu * dir[u] + this.nv * dir[v]; | |
var t = (this.nd - orig[this.axis] - this.nu * orig[u] - this.nv * orig[v]) / d; | |
if (t < near || t > far) | |
return null; | |
var Pu = orig[u] + t * dir[u] - this.eu; | |
var Pv = orig[v] + t * dir[v] - this.ev; | |
var a2 = Pv * this.nu1 + Pu * this.nv1; | |
if (a2 < 0) | |
return null; | |
var a3 = Pu * this.nu2 + Pv * this.nv2; | |
if (a3 < 0) | |
return null; | |
if ((a2 + a3) > 1) | |
return null; | |
return t; | |
} | |
function Scene(a_triangles) { | |
this.triangles = a_triangles; | |
this.lights = []; | |
this.ambient = [0,0,0]; | |
this.background = [0.8,0.8,1]; | |
} | |
var zero = new Array(0,0,0); | |
Scene.prototype.intersect = function(origin, dir, near, far) { | |
var closest = null; | |
for (i = 0; i < this.triangles.length; i++) { | |
var triangle = this.triangles[i]; | |
var d = triangle.intersect(origin, dir, near, far); | |
if (d == null || d > far || d < near) | |
continue; | |
far = d; | |
closest = triangle; | |
} | |
if (!closest) | |
return [this.background[0],this.background[1],this.background[2]]; | |
var normal = closest.normal; | |
var hit = add(origin, scale(dir, far)); | |
if (dot(dir, normal) > 0) | |
normal = [-normal[0], -normal[1], -normal[2]]; | |
var colour = null; | |
if (closest.shader) { | |
colour = closest.shader(closest, hit, dir); | |
} else { | |
colour = closest.material; | |
} | |
// do reflection | |
var reflected = null; | |
if (colour.reflection > 0.001) { | |
var reflection = addVector(scale(normal, -2*dot(dir, normal)), dir); | |
reflected = this.intersect(hit, reflection, 0.0001, 1000000); | |
if (colour.reflection >= 0.999999) | |
return reflected; | |
} | |
var l = [this.ambient[0], this.ambient[1], this.ambient[2]]; | |
for (var i = 0; i < this.lights.length; i++) { | |
var light = this.lights[i]; | |
var toLight = sub(light, hit); | |
var distance = lengthVector(toLight); | |
scaleVector(toLight, 1.0/distance); | |
distance -= 0.0001; | |
if (this.blocked(hit, toLight, distance)) | |
continue; | |
var nl = dot(normal, toLight); | |
if (nl > 0) | |
addVector(l, scale(light.colour, nl)); | |
} | |
l = scalev(l, colour); | |
if (reflected) { | |
l = addVector(scaleVector(l, 1 - colour.reflection), scaleVector(reflected, colour.reflection)); | |
} | |
return l; | |
} | |
Scene.prototype.blocked = function(O, D, far) { | |
var near = 0.0001; | |
var closest = null; | |
for (i = 0; i < this.triangles.length; i++) { | |
var triangle = this.triangles[i]; | |
var d = triangle.intersect(O, D, near, far); | |
if (d == null || d > far || d < near) | |
continue; | |
return true; | |
} | |
return false; | |
} | |
// this camera code is from notes i made ages ago, it is from *somewhere* -- i cannot remember where | |
// that somewhere is | |
function Camera(origin, lookat, up) { | |
var zaxis = normaliseVector(subVector(lookat, origin)); | |
var xaxis = normaliseVector(cross(up, zaxis)); | |
var yaxis = normaliseVector(cross(xaxis, subVector([0,0,0], zaxis))); | |
var m = new Array(16); | |
m[0] = xaxis[0]; m[1] = xaxis[1]; m[2] = xaxis[2]; | |
m[4] = yaxis[0]; m[5] = yaxis[1]; m[6] = yaxis[2]; | |
m[8] = zaxis[0]; m[9] = zaxis[1]; m[10] = zaxis[2]; | |
invertMatrix(m); | |
m[3] = 0; m[7] = 0; m[11] = 0; | |
this.origin = origin; | |
this.directions = new Array(4); | |
this.directions[0] = normalise([-0.7, 0.7, 1]); | |
this.directions[1] = normalise([ 0.7, 0.7, 1]); | |
this.directions[2] = normalise([ 0.7, -0.7, 1]); | |
this.directions[3] = normalise([-0.7, -0.7, 1]); | |
this.directions[0] = transformMatrix(m, this.directions[0]); | |
this.directions[1] = transformMatrix(m, this.directions[1]); | |
this.directions[2] = transformMatrix(m, this.directions[2]); | |
this.directions[3] = transformMatrix(m, this.directions[3]); | |
} | |
Camera.prototype.generateRayPair = function(y) { | |
rays = new Array(new Object(), new Object()); | |
rays[0].origin = this.origin; | |
rays[1].origin = this.origin; | |
rays[0].dir = addVector(scale(this.directions[0], y), scale(this.directions[3], 1 - y)); | |
rays[1].dir = addVector(scale(this.directions[1], y), scale(this.directions[2], 1 - y)); | |
return rays; | |
} | |
function renderRows(camera, scene, pixels, width, height, starty, stopy) { | |
for (var y = starty; y < stopy; y++) { | |
var rays = camera.generateRayPair(y / height); | |
for (var x = 0; x < width; x++) { | |
var xp = x / width; | |
var origin = addVector(scale(rays[0].origin, xp), scale(rays[1].origin, 1 - xp)); | |
var dir = normaliseVector(addVector(scale(rays[0].dir, xp), scale(rays[1].dir, 1 - xp))); | |
var l = scene.intersect(origin, dir); | |
pixels[y][x] = l; | |
} | |
} | |
} | |
Camera.prototype.render = function(scene, pixels, width, height) { | |
var cam = this; | |
var row = 0; | |
renderRows(cam, scene, pixels, width, height, 0, height); | |
} | |
function raytraceScene() | |
{ | |
var startDate = new Date().getTime(); | |
var numTriangles = 2 * 6; | |
var triangles = new Array();//numTriangles); | |
var tfl = createVector(-10, 10, -10); | |
var tfr = createVector( 10, 10, -10); | |
var tbl = createVector(-10, 10, 10); | |
var tbr = createVector( 10, 10, 10); | |
var bfl = createVector(-10, -10, -10); | |
var bfr = createVector( 10, -10, -10); | |
var bbl = createVector(-10, -10, 10); | |
var bbr = createVector( 10, -10, 10); | |
// cube!!! | |
// front | |
var i = 0; | |
triangles[i++] = new Triangle(tfl, tfr, bfr); | |
triangles[i++] = new Triangle(tfl, bfr, bfl); | |
// back | |
triangles[i++] = new Triangle(tbl, tbr, bbr); | |
triangles[i++] = new Triangle(tbl, bbr, bbl); | |
// triangles[i-1].material = [0.7,0.2,0.2]; | |
// triangles[i-1].material.reflection = 0.8; | |
// left | |
triangles[i++] = new Triangle(tbl, tfl, bbl); | |
// triangles[i-1].reflection = 0.6; | |
triangles[i++] = new Triangle(tfl, bfl, bbl); | |
// triangles[i-1].reflection = 0.6; | |
// right | |
triangles[i++] = new Triangle(tbr, tfr, bbr); | |
triangles[i++] = new Triangle(tfr, bfr, bbr); | |
// top | |
triangles[i++] = new Triangle(tbl, tbr, tfr); | |
triangles[i++] = new Triangle(tbl, tfr, tfl); | |
// bottom | |
triangles[i++] = new Triangle(bbl, bbr, bfr); | |
triangles[i++] = new Triangle(bbl, bfr, bfl); | |
//Floor!!!! | |
var green = createVector(0.0, 0.4, 0.0); | |
var grey = createVector(0.4, 0.4, 0.4); | |
grey.reflection = 1.0; | |
var floorShader = function(tri, pos, view) { | |
var x = ((pos[0]/32) % 2 + 2) % 2; | |
var z = ((pos[2]/32 + 0.3) % 2 + 2) % 2; | |
if (x < 1 != z < 1) { | |
//in the real world we use the fresnel term... | |
// var angle = 1-dot(view, tri.normal); | |
// angle *= angle; | |
// angle *= angle; | |
// angle *= angle; | |
//grey.reflection = angle; | |
return grey; | |
} else | |
return green; | |
} | |
var ffl = createVector(-1000, -30, -1000); | |
var ffr = createVector( 1000, -30, -1000); | |
var fbl = createVector(-1000, -30, 1000); | |
var fbr = createVector( 1000, -30, 1000); | |
triangles[i++] = new Triangle(fbl, fbr, ffr); | |
triangles[i-1].shader = floorShader; | |
triangles[i++] = new Triangle(fbl, ffr, ffl); | |
triangles[i-1].shader = floorShader; | |
var _scene = new Scene(triangles); | |
_scene.lights[0] = createVector(20, 38, -22); | |
_scene.lights[0].colour = createVector(0.7, 0.3, 0.3); | |
_scene.lights[1] = createVector(-23, 40, 17); | |
_scene.lights[1].colour = createVector(0.7, 0.3, 0.3); | |
_scene.lights[2] = createVector(23, 20, 17); | |
_scene.lights[2].colour = createVector(0.7, 0.7, 0.7); | |
_scene.ambient = createVector(0.1, 0.1, 0.1); | |
// _scene.background = createVector(0.7, 0.7, 1.0); | |
var size = 30; | |
var pixels = new Array(); | |
for (var y = 0; y < size; y++) { | |
pixels[y] = new Array(); | |
for (var x = 0; x < size; x++) { | |
pixels[y][x] = 0; | |
} | |
} | |
var _camera = new Camera(createVector(-40, 40, 40), createVector(0, 0, 0), createVector(0, 1, 0)); | |
_camera.render(_scene, pixels, size, size); | |
return pixels; | |
} | |
function arrayToCanvasCommands(pixels) | |
{ | |
var s = '<canvas id="renderCanvas" width="30px" height="30px"></canvas><scr' + 'ipt>\nvar pixels = ['; | |
var size = 30; | |
for (var y = 0; y < size; y++) { | |
s += "["; | |
for (var x = 0; x < size; x++) { | |
s += "[" + pixels[y][x] + "],"; | |
} | |
s+= "],"; | |
} | |
s += '];\n var canvas = document.getElementById("renderCanvas").getContext("2d");\n\ | |
\n\ | |
\n\ | |
var size = 30;\n\ | |
canvas.fillStyle = "red";\n\ | |
canvas.fillRect(0, 0, size, size);\n\ | |
canvas.scale(1, -1);\n\ | |
canvas.translate(0, -size);\n\ | |
\n\ | |
if (!canvas.setFillColor)\n\ | |
canvas.setFillColor = function(r, g, b, a) {\n\ | |
this.fillStyle = "rgb("+[Math.floor(r * 255), Math.floor(g * 255), Math.floor(b * 255)]+")";\n\ | |
}\n\ | |
\n\ | |
for (var y = 0; y < size; y++) {\n\ | |
for (var x = 0; x < size; x++) {\n\ | |
var l = pixels[y][x];\n\ | |
canvas.setFillColor(l[0], l[1], l[2], 1);\n\ | |
canvas.fillRect(x, y, 1, 1);\n\ | |
}\n\ | |
}</scr' + 'ipt>'; | |
return s; | |
} | |
testOutput = arrayToCanvasCommands(raytraceScene()); | |
log(testOutput); | |
//var expectedLength = 20970; | |
//if (testOutput.length != expectedLength) | |
// throw "Error: bad result: expected length " + expectedLength + " but got " + testOutput.length; |
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