I'm trying to do a simple scene using rayTracing with js. I'm trying to draw a sphere and calculate the colors.
The code works fine without calculating the colors. Only drawing the sphere with plane colors when whe detect the sphere using de ray.
However, when I trie to put the colors I've some errors. It says that vec 3 is undeclared and I can't find why. I think it's a very stupid mistake but I can't find it. Can u help me please?
Also if you know and want you can give me some advices or corrections to do the task I want to do.
PD: The vec3 js it's one I found in Internet with some modifications. Sorry for my english I'm from Spain.
/* Copyright (c) 2013, Brandon Jones, Colin MacKenzie IV. All rights reserved.
Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
* 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 THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 THE COPYRIGHT HOLDER 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. */
/**
* @class 3 Dimensional Vector
* @name vec3
*/
var vec3 = {};
vec3.ZERO = { x: 0, y: 0, z: 0 };
/**
* Creates a new, empty vec3
*
* @returns {vec3} a new 3D vector
*/
vec3.create = function() {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = 0;
out[1] = 0;
out[2] = 0;
return out;
};
/**
* Creates a new vec3 initialized with values from an existing vector
*
* @param {vec3} a vector to clone
* @returns {vec3} a new 3D vector
*/
vec3.clone = function(a) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = a[0];
out[1] = a[1];
out[2] = a[2];
return out;
};
vec3.unitVector = function(a){
return vec3.scale(a, 1/vec3.len(a));
};
/**
* Creates a new vec3 initialized with the given values
*
* @param {Number} x X component
* @param {Number} y Y component
* @param {Number} z Z component
* @returns {vec3} a new 3D vector
*/
vec3.fromValues = function(x, y, z) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = x;
out[1] = y;
out[2] = z;
return out;
};
/**
* Copy the values from one vec3 to another
*
* @param {vec3} out the receiving vector
* @param {vec3} a the source vector
* @returns {vec3} out
*/
vec3.copy = function(a) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = a[0];
out[1] = a[1];
out[2] = a[2];
return out;
};
/**
* Set the components of a vec3 to the given values
*
* @param {vec3} out the receiving vector
* @param {Number} x X component
* @param {Number} y Y component
* @param {Number} z Z component
* @returns {vec3} out
*/
vec3.set = function(x, y, z) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = x;
out[1] = y;
out[2] = z;
return out;
};
/**
* Adds two vec3's
*
* @param {vec3} out the receiving vector
* @param {vec3} a the first operand
* @param {vec3} b the second operand
* @returns {vec3} out
*/
vec3.add = function(a, b) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = a[0] + b[0];
out[1] = a[1] + b[1];
out[2] = a[2] + b[2];
return out;
};
vec3.unitVector = function(a){
return vec3.scale(a, 1/vec3.len(a));
};
vec3.reflectThrough = function(a, normal){
var d = vec3.scale(normal, vec.dot(a,normal));
return vec3.substract(vec3.scale(d,2),a);
};
/**
* Adds three vec3's
*
* @param {vec3} out the receiving vector
* @param {vec3} a the first operand
* @param {vec3} b the second operand
* @returns {vec3} out
*/
vec3.add3 = function(a, b, c) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = a[0] + b[0] + c[0];
out[1] = a[1] + b[1] + c[1];
out[2] = a[2] + b[2] + c[2];
return out;
};
/**
* Subtracts vector b from vector a
*
* @param {vec3} out the receiving vector
* @param {vec3} a the first operand
* @param {vec3} b the second operand
* @returns {vec3} out
*/
vec3.subtract = function(a, b) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = a[0] - b[0];
out[1] = a[1] - b[1];
out[2] = a[2] - b[2];
return out;
};
/**
* Alias for {@link vec3.subtract}
* @function
*/
vec3.sub = vec3.subtract;
/**
* Multiplies two vec3's
*
* @param {vec3} out the receiving vector
* @param {vec3} a the first operand
* @param {vec3} b the second operand
* @returns {vec3} out
*/
vec3.multiply = function(a, b) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = a[0] * b[0];
out[1] = a[1] * b[1];
out[2] = a[2] * b[2];
return out;
};
/**
* Alias for {@link vec3.multiply}
* @function
*/
vec3.mul = vec3.multiply;
/**
* Divides two vec3's
*
* @param {vec3} out the receiving vector
* @param {vec3} a the first operand
* @param {vec3} b the second operand
* @returns {vec3} out
*/
vec3.divide = function(a, b) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = a[0] / b[0];
out[1] = a[1] / b[1];
out[2] = a[2] / b[2];
return out;
};
/**
* Alias for {@link vec3.divide}
* @function
*/
vec3.div = vec3.divide;
/**
* Returns the minimum of two vec3's
*
* @param {vec3} out the receiving vector
* @param {vec3} a the first operand
* @param {vec3} b the second operand
* @returns {vec3} out
*/
vec3.min = function(a, b) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = Math.min(a[0], b[0]);
out[1] = Math.min(a[1], b[1]);
out[2] = Math.min(a[2], b[2]);
return out;
};
/**
* Returns the maximum of two vec3's
*
* @param {vec3} out the receiving vector
* @param {vec3} a the first operand
* @param {vec3} b the second operand
* @returns {vec3} out
*/
vec3.max = function(a, b) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = Math.max(a[0], b[0]);
out[1] = Math.max(a[1], b[1]);
out[2] = Math.max(a[2], b[2]);
return out;
};
/**
* Scales a vec3 by a scalar number
*
* @param {vec3} out the receiving vector
* @param {vec3} a the vector to scale
* @param {Number} b amount to scale the vector by
* @returns {vec3} out
*/
vec3.scale = function(a, b) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = a[0] * b;
out[1] = a[1] * b;
out[2] = a[2] * b;
return out;
};
/**
* Adds two vec3's after scaling the second operand by a scalar value
*
* @param {vec3} out the receiving vector
* @param {vec3} a the first operand
* @param {vec3} b the second operand
* @param {Number} scale the amount to scale b by before adding
* @returns {vec3} out
*/
vec3.scaleAndAdd = function(a, b, scale) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = a[0] + (b[0] * scale);
out[1] = a[1] + (b[1] * scale);
out[2] = a[2] + (b[2] * scale);
return out;
};
/**
* Calculates the euclidian distance between two vec3's
*
* @param {vec3} a the first operand
* @param {vec3} b the second operand
* @returns {Number} distance between a and b
*/
vec3.distance = function(a, b) {
var x = b[0] - a[0],
y = b[1] - a[1],
z = b[2] - a[2];
return Math.sqrt(x*x + y*y + z*z);
};
/**
* Alias for {@link vec3.distance}
* @function
*/
vec3.dist = vec3.distance;
/**
* Calculates the squared euclidian distance between two vec3's
*
* @param {vec3} a the first operand
* @param {vec3} b the second operand
* @returns {Number} squared distance between a and b
*/
vec3.squaredDistance = function(a, b) {
var x = b[0] - a[0],
y = b[1] - a[1],
z = b[2] - a[2];
return x*x + y*y + z*z;
};
/**
* Alias for {@link vec3.squaredDistance}
* @function
*/
vec3.sqrDist = vec3.squaredDistance;
/**
* Calculates the length of a vec3
*
* @param {vec3} a vector to calculate length of
* @returns {Number} length of a
*/
vec3.length = function (a) {
var x = a[0],
y = a[1],
z = a[2];
return Math.sqrt(x*x + y*y + z*z);
};
/**
* Alias for {@link vec3.length}
* @function
*/
vec3.len = vec3.length;
/**
* Calculates the squared length of a vec3
*
* @param {vec3} a vector to calculate squared length of
* @returns {Number} squared length of a
*/
vec3.squaredLength = function (a) {
var x = a[0],
y = a[1],
z = a[2];
return x*x + y*y + z*z;
};
/**
* Alias for {@link vec3.squaredLength}
* @function
*/
vec3.sqrLen = vec3.squaredLength;
/**
* Negates the components of a vec3
*
* @param {vec3} out the receiving vector
* @param {vec3} a vector to negate
* @returns {vec3} out
*/
vec3.negate = function(a) {
var out = new GLMAT_ARRAY_TYPE(3);
out[0] = -a[0];
out[1] = -a[1];
out[2] = -a[2];
return out;
};
/**
* Normalize a vec3
*
* @param {vec3} out the receiving vector
* @param {vec3} a vector to normalize
* @returns {vec3} out
*/
vec3.normalize = function(a) {
var out = new GLMAT_ARRAY_TYPE(3);
var x = a[0],
y = a[1],
z = a[2];
var len = x*x + y*y + z*z;
if (len > 0) {
//TODO: evaluate use of glm_invsqrt here?
len = 1 / Math.sqrt(len);
out[0] = a[0] * len;
out[1] = a[1] * len;
out[2] = a[2] * len;
}
return out;
};
/**
* Calculates the dot product of two vec3's
*
* @param {vec3} a the first operand
* @param {vec3} b the second operand
* @returns {Number} dot product of a and b
*/
vec3.dot = function (a, b) {
return a[0] * b[0] + a[1] * b[1] + a[2] * b[2];
};
/**
* Computes the cross product of two vec3's
*
* @param {vec3} out the receiving vector
* @param {vec3} a the first operand
* @param {vec3} b the second operand
* @returns {vec3} out
*/
vec3.cross = function(a, b) {
var out = new GLMAT_ARRAY_TYPE(3);
var ax = a[0], ay = a[1], az = a[2],
bx = b[0], by = b[1], bz = b[2];
out[0] = ay * bz - az * by;
out[1] = az * bx - ax * bz;
out[2] = ax * by - ay * bx;
return out;
};
/**
* Performs a linear interpolation between two vec3's
*
* @param {vec3} out the receiving vector
* @param {vec3} a the first operand
* @param {vec3} b the second operand
* @param {Number} t interpolation amount between the two inputs
* @returns {vec3} out
*/
vec3.lerp = function (a, b, t) {
var out = new GLMAT_ARRAY_TYPE(3);
var ax = a[0],
ay = a[1],
az = a[2];
out[0] = ax + t * (b[0] - ax);
out[1] = ay + t * (b[1] - ay);
out[2] = az + t * (b[2] - az);
return out;
};
/**
* Generates a random vector with the given scale
*
* @param {vec3} out the receiving vector
* @param {Number} [scale] Length of the resulting vector. If ommitted, a unit vector will be returned
* @returns {vec3} out
*/
vec3.random = function (scale) {
var out = new GLMAT_ARRAY_TYPE(3);
scale = scale || 1.0;
var r = GLMAT_RANDOM() * 2.0 * Math.PI;
var z = (GLMAT_RANDOM() * 2.0) - 1.0;
var zScale = Math.sqrt(1.0-z*z) * scale;
out[0] = Math.cos(r) * zScale;
out[1] = Math.sin(r) * zScale;
out[2] = z * scale;
return out;
};
/**
* Transforms the vec3 with a mat4.
* 4th vector component is implicitly '1'
*
* @param {vec3} out the receiving vector
* @param {vec3} a the vector to transform
* @param {mat4} m matrix to transform with
* @returns {vec3} out
*/
vec3.transformMat4 = function(a, m) {
var out = new GLMAT_ARRAY_TYPE(3);
var x = a[0], y = a[1], z = a[2];
out[0] = m[0] * x + m[4] * y + m[8] * z + m[12];
out[1] = m[1] * x + m[5] * y + m[9] * z + m[13];
out[2] = m[2] * x + m[6] * y + m[10] * z + m[14];
return out;
};
/**
* Transforms the vec3 with a mat3.
*
* @param {vec3} out the receiving vector
* @param {vec3} a the vector to transform
* @param {mat4} m the 3x3 matrix to transform with
* @returns {vec3} out
*/
vec3.transformMat3 = function(a, m) {
var out = new GLMAT_ARRAY_TYPE(3);
var x = a[0], y = a[1], z = a[2];
out[0] = x * m[0] + y * m[3] + z * m[6];
out[1] = x * m[1] + y * m[4] + z * m[7];
out[2] = x * m[2] + y * m[5] + z * m[8];
return out;
};
/**
* Transforms the vec3 with a quat
*
* @param {vec3} out the receiving vector
* @param {vec3} a the vector to transform
* @param {quat} q quaternion to transform with
* @returns {vec3} out
*/
vec3.transformQuat = function(a, q) {
var out = new GLMAT_ARRAY_TYPE(3);
// benchmarks: http://jsperf.com/quaternion-transform-vec3-implementations
var x = a[0], y = a[1], z = a[2],
qx = q[0], qy = q[1], qz = q[2], qw = q[3],
// calculate quat * vec
ix = qw * x + qy * z - qz * y,
iy = qw * y + qz * x - qx * z,
iz = qw * z + qx * y - qy * x,
iw = -qx * x - qy * y - qz * z;
// calculate result * inverse quat
out[0] = ix * qw + iw * -qx + iy * -qz - iz * -qy;
out[1] = iy * qw + iw * -qy + iz * -qx - ix * -qz;
out[2] = iz * qw + iw * -qz + ix * -qy - iy * -qx;
return out;
};
/**
* Perform some operation over an array of vec3s.
*
* @param {Array} a the array of vectors to iterate over
* @param {Number} stride Number of elements between the start of each vec3. If 0 assumes tightly packed
* @param {Number} offset Number of elements to skip at the beginning of the array
* @param {Number} count Number of vec3s to iterate over. If 0 iterates over entire array
* @param {Function} fn Function to call for each vector in the array
* @param {Object} [arg] additional argument to pass to fn
* @returns {Array} a
* @function
*/
vec3.forEach = (function() {
var vec = vec3.create();
return function(a, stride, offset, count, fn, arg) {
var i, l;
if(!stride) {
stride = 3;
}
if(!offset) {
offset = 0;
}
if(count) {
l = Math.min((count * stride) + offset, a.length);
} else {
l = a.length;
}
for(i = offset; i < l; i += stride) {
vec[0] = a[i]; vec[1] = a[i+1]; vec[2] = a[i+2];
fn(vec, vec, arg);
a[i] = vec[0]; a[i+1] = vec[1]; a[i+2] = vec[2];
}
return a;
};
})();
/**
* Returns a string representation of a vector
*
* @param {vec3} vec vector to represent as a string
* @returns {String} string representation of the vector
*/
vec3.str = function (a) {
return 'vec3(' + a[0] + ', ' + a[1] + ', ' + a[2] + ')';
};
if(typeof(exports) !== 'undefined') {
exports.vec3 = vec3;
}
HTML
<html>
<head>
<title>Ray Tracing Example</title>
</head>
<body>
<h1>Ray Tracing</h1>
<table>
<th>
<canvas id="glcanvas" style="border: solid;" width="400" height="400"></canvas>
<button onclick="start()"> Start </button>
</th>
</table>
<p style="text-indent:85px;">Camera Position: [0, 0, 0]</p>
<script type="text/javascript" src="raytracingV2.js"></script>
<script src="gl-matrix/common.js"></script>
<script type="text/javascript" src="gl-matrix/vec3.js"></script>
<script type="text/javascript" src="gl-matrix/vec2.js"></script>
<script type="text/javascript" src="gl-matrix/vec4.js"></script>
<script type="text/javascript" src="gl-matrix/vec4.js"></script>
<script type="text/javascript" src="gl-matrix/mat4.js"></script>
<script type="text/javascript" src="gl-matrix/mat3.js"></script>
<script type="text/javascript" src="gl-matrix/quat.js"></script>
<script type="text/javascript">
function start () {
// Inicialitzem el RayTracing
inicialitzar(Scene);
}
var Screen = {
width : 0,
height : 0,
canvas : null,
context : null,
buffer : null,
};
var Scene = {
Fons: [0, 0, 0],
Shapes: [
{
id : "pla_groc",
tipus : "pla",
normal : [0,1,0],
point : {
x: 0,
y: 3.5,
z: -3,
},
// Material:
// Rd, Rs, Ra (colors)
// alpha specular (float)
// Reflexion and/or Transmision (float)
},
{
id : "pla_blau",
tipus : "pla",
normal : [0,0,1],
point : {
x: 0,
y: 0,
z: 0,
},
// Material:
// Rd, Rs, Ra (colors)
// alpha specular (float)
// Reflexion and/or Transmision (float)
},
{
id : "esfera_blava",
tipus : "esfera",
radi : 1.5,
centre : [-1.5,1.3,1],
point : [-1.5,1.3,1],
color:{
x: 155,
y: 200,
z: 155,
},
specular: 0.2,
lambert: 0.7,
ambient: 0.1,
// Material:
// Rd, Rs, Ra (colors)
// alpha specular (float)
// Reflexion and/or Transmision (float)
},
],
Camera: {
position: [0,0,0], // posicio camera
up : [0,1,0], // vector amunt
centre : [0,0,-1], // centre escena
fov : 60, // field of view
X : vec3.create(),
Z : vec3.create(),
Y : vec3.create(),
},
Lights: [
{
position: vec3.create(), // S'emplena segons els valors entrats
color : vec3.create(), // S'emplena segons els valors entrats
},
{
position: vec3.create(), // S'emplena segons els valors entrats
color : vec3.create(), // S'emplena segons els valors entrats
},
]
};
</script>
</body>
</html>
JS
// RAY TRACING - example //
const { vec3 } = require("./gl-matrix/vec3");
// Inicialitzem el RayTracing
function inicialitzar(Scene) {
// Parametres de les llums
// Put it interactively
Scene.Lights[0].position = [0, 0, 0];
Scene.Lights[0].color = [0.67, 0.67, 0.67, 1];
Screen.canvas = document.getElementById("glcanvas");
if (Screen.canvas == null) {
alert("Invalid element: " + id);
return;
}
Screen.context = Screen.canvas.getContext("2d");
if(Screen.context == null){
alert("Could not get context");
return;
}
Screen.width = Screen.canvas.width;
Screen.height = Screen.canvas.height;
Screen.buffer = Screen.context.createImageData(Screen.width,Screen.height);
// Calculem els eixos de la camera
calcularEixos(Scene);
// Calculem els increments i P0 (GLOBALS)
incX = calcularIncrementX(Scene.Camera,Screen);
incY = calcularIncrementY(Scene.Camera,Screen);
P0 = calcularP0(incX,incY,Scene.Camera,Screen);
// Executem RayTracing
rayTracing(Scene, Screen);
Screen.context.putImageData(Screen.buffer, 0, 0);
};
function sphereIntersection(sphere, ray){
var eye_to_center = vec3.subtract(sphere.point, vec3.clone(ray));
var v = vec3.dot(eye_to_center, vec3.clone(ray));
var eoDot = vec3.dot(eye_to_center,eye_to_center);
var discriminant = sphere.radi * sphere.radi -eoDot + v * v;
if (discriminant<0){
return;
}else{
return v - Math.sqrt(discriminant);
}
}
// Calcular increment de X
function calcularIncrementX(Cam,Scr) {
var rati = (Scr.height/Scr.width);
var theta = (Cam.fov * Math.PI / 180);
var w = 2*Math.tan(theta/2); // Calculem w' = 2*tg(theta/2)
var h = w*rati; // Calculem h' = w'*rati
var aux = w/Scr.width; // w'/W
var incX = vec3.scale(Cam.X,aux); // Calculem increment de X (X * 2*tg(theta/2)/W)
return incX;
}
// Calcular increment de Y
function calcularIncrementY(Cam,Scr) {
var rati = (Scr.height/Scr.width);
var theta = (Cam.fov * Math.PI / 180);
var w = 2*Math.tan(theta/2); // Calculem w' = 2*tg(theta/2)
var h = w*rati; // Calculem h' = w'*rati
var aux = rati*w/Scr.height; // rati*w'/H
var incY = vec3.scale(Cam.Y,aux); // Calculem increment de Y (Y * 2*tg(theta/2)/W)
return incY;
}
function isLightVisible(pt, scene, light){
var distObject = intersectarScene(
{
point:pt,
vector: vec3.unitVector(vec3.substract(pt, light)),
},
scene
);
return distObject[0] > -0.005;
}
function surface(ray, scene, object, pointAtTime, normal, depth){
var b = object.color;
var c = vec3.ZERO;
var lambertAmount = 0;
if (object.lambert){
for (var i = 0; i<scene.Lights.length; i++){
var lightPoint = scene.lights[i];
if (!isLightVisible(pointAtTime, scene, lightPoint)) continue;
var contribution = vec3.dot(vec3.unitVector(vec3.subtract(lightPoint, pointAtTime)), normal);
if (contribution > 0) lambertAmount += contribution;
}
}
if (object.specular){
var reflectedRay = {
point: pointAtTime,
vector: vec3.reflectThrough(vec3.clone(ray), normal),
};
var reflectedColor = trace(reflectedRay, scene, ++depth);
if(reflectedColor){
c = vec3.add(c, vec3.scale(reflectedColor, object.specular));
}
}
lambertAmount = Math.min(1,lambertAmount);
return vec3.add3(c, vec3.scale(b, lambertAmount * object.lambert), vec3.scale(b, object.ambient));
}
// Calcular P0
function calcularP0(incX,incY,Cam,Scr) {
var P = vec3.subtract(Cam.position,Cam.Z); // Calculem P (O - Z)
var aux = vec3.scale(incX,((Scr.width-1)/2)); // Increment de X * (W-1)/2
var aux2 = vec3.scale(incY,((Scr.height-1)/2)); // Increment de Y * (H-1)/2
var aux3 = vec3.subtract(P,aux); // P - Increment de X * (W-1)/2
var P0 = vec3.add(aux3,aux2); // Calculem P0 (P - Increment de X * (W-1)/2 + Increment de Y * (H-1)/2)
return P0;
}
// Calcular els eixos de la camera
function calcularEixos(Scene) {
Scene.Camera.Z = vec3.normalize(vec3.subtract(Scene.Camera.position, Scene.Camera.centre)); // |O - C|
Scene.Camera.X = vec3.normalize(vec3.cross(Scene.Camera.up, Scene.Camera.Z)); // |up x Z|
Scene.Camera.Y = vec3.cross(Scene.Camera.Z, Scene.Camera.X); // Z x X
}
function plot(x,y,color){
var index = (x+y*Screen.buffer.width)*4;
Screen.buffer.data[index+0] = color[0] * 255;
Screen.buffer.data[index+1] = color[1] * 255;
Screen.buffer.data[index+2] = color[2] * 255;
Screen.buffer.data[index+3] = 255;
return index;
}
function sphereNormal(sphere, pos) {
return vec3.unitVector(vec3.subtract(pos, sphere.point));
}
function intersectarScene(scene, ray) {
var object = scene.Shapes[2];
var closest = [Infinity, null];
var dist = sphereIntersection(object, ray);
if (dist !== undefined && dist < closest[0]) {
closest = [dist, object];
}
return closest;
}
function trace(ray, scene, depth){
if (depth > 3) return;
var distObject = intersectarScene(ray,scene);
if (distObject[0] === Infinity) {
return Vector.WHITE;
}
var dist = distObject[0];
var object = distObject[1];
var pointAtTime = vector3.add(ray.point, Vector.scale(vec3.clone(ray), dist));
return surface(ray,scene,object,pointAtTime, sphereNormal(object, pointAtTime), depth);
}
// Pintar cada pixel
function rayTracing(Scene, Screen) {
console.log(incX);
for(var x = 0; x < Screen.width; x++){
for (y = 0; y < Screen.height; y++){
var rDirection = computeRay(incX,incY,P0,Scene.Camera,x,y);
var color = trace(rDirection, Scene, 0);
plot(x,y,color);
}
}
}
// Computar el raig
function computeRay(incX,incY,P0,Cam,x,y){
// Calculem la direccio per a cada pixel
var aux = vec3.scale(incX,x); // Increment de X * x
var aux2 = vec3.scale(incY,y); // Increment de Y * y
var aux3 = vec3.add(P0,aux); // P0 + Increment de X * x
var aux4 = vec3.subtract(aux3,aux2); // P0 + Increment de X * x - Increment de Y * y
var ray = vec3.subtract(aux4,Cam.position); // Obtenim raig (P0 + Increment de X * x - Increment de Y * y - O)
var rayNorm = vec3.normalize(ray); // Normalitzem el raig
return rayNorm;
}
