Cesium-Examples/examples/webglEx/glMatrix-0.9.6.js
2025-03-11 17:51:04 +08:00

1835 lines
41 KiB
JavaScript

/*
* glMatrix.js - High performance matrix and vector operations for WebGL
* version 0.9.6
*/
/*
* Copyright (c) 2011 Brandon Jones
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
*
* 2. Altered source versions must be plainly marked as such, and must not
* be misrepresented as being the original software.
*
* 3. This notice may not be removed or altered from any source
* distribution.
*/
// Fallback for systems that don't support WebGL
if(typeof Float32Array != 'undefined') {
glMatrixArrayType = Float32Array;
} else if(typeof WebGLFloatArray != 'undefined') {
glMatrixArrayType = WebGLFloatArray; // This is officially deprecated and should dissapear in future revisions.
} else {
glMatrixArrayType = Array;
}
/*
* vec3 - 3 Dimensional Vector
*/
var vec3 = {};
/*
* vec3.create
* Creates a new instance of a vec3 using the default array type
* Any javascript array containing at least 3 numeric elements can serve as a vec3
*
* Params:
* vec - Optional, vec3 containing values to initialize with
*
* Returns:
* New vec3
*/
vec3.create = function(vec) {
var dest = new glMatrixArrayType(3);
if(vec) {
dest[0] = vec[0];
dest[1] = vec[1];
dest[2] = vec[2];
}
return dest;
};
/*
* vec3.set
* Copies the values of one vec3 to another
*
* Params:
* vec - vec3 containing values to copy
* dest - vec3 receiving copied values
*
* Returns:
* dest
*/
vec3.set = function(vec, dest) {
dest[0] = vec[0];
dest[1] = vec[1];
dest[2] = vec[2];
return dest;
};
/*
* vec3.add
* Performs a vector addition
*
* Params:
* vec - vec3, first operand
* vec2 - vec3, second operand
* dest - Optional, vec3 receiving operation result. If not specified result is written to vec
*
* Returns:
* dest if specified, vec otherwise
*/
vec3.add = function(vec, vec2, dest) {
if(!dest || vec == dest) {
vec[0] += vec2[0];
vec[1] += vec2[1];
vec[2] += vec2[2];
return vec;
}
dest[0] = vec[0] + vec2[0];
dest[1] = vec[1] + vec2[1];
dest[2] = vec[2] + vec2[2];
return dest;
};
/*
* vec3.subtract
* Performs a vector subtraction
*
* Params:
* vec - vec3, first operand
* vec2 - vec3, second operand
* dest - Optional, vec3 receiving operation result. If not specified result is written to vec
*
* Returns:
* dest if specified, vec otherwise
*/
vec3.subtract = function(vec, vec2, dest) {
if(!dest || vec == dest) {
vec[0] -= vec2[0];
vec[1] -= vec2[1];
vec[2] -= vec2[2];
return vec;
}
dest[0] = vec[0] - vec2[0];
dest[1] = vec[1] - vec2[1];
dest[2] = vec[2] - vec2[2];
return dest;
};
/*
* vec3.negate
* Negates the components of a vec3
*
* Params:
* vec - vec3 to negate
* dest - Optional, vec3 receiving operation result. If not specified result is written to vec
*
* Returns:
* dest if specified, vec otherwise
*/
vec3.negate = function(vec, dest) {
if(!dest) { dest = vec; }
dest[0] = -vec[0];
dest[1] = -vec[1];
dest[2] = -vec[2];
return dest;
};
/*
* vec3.scale
* Multiplies the components of a vec3 by a scalar value
*
* Params:
* vec - vec3 to scale
* val - Numeric value to scale by
* dest - Optional, vec3 receiving operation result. If not specified result is written to vec
*
* Returns:
* dest if specified, vec otherwise
*/
vec3.scale = function(vec, val, dest) {
if(!dest || vec == dest) {
vec[0] *= val;
vec[1] *= val;
vec[2] *= val;
return vec;
}
dest[0] = vec[0]*val;
dest[1] = vec[1]*val;
dest[2] = vec[2]*val;
return dest;
};
/*
* vec3.normalize
* Generates a unit vector of the same direction as the provided vec3
* If vector length is 0, returns [0, 0, 0]
*
* Params:
* vec - vec3 to normalize
* dest - Optional, vec3 receiving operation result. If not specified result is written to vec
*
* Returns:
* dest if specified, vec otherwise
*/
vec3.normalize = function(vec, dest) {
if(!dest) { dest = vec; }
var x = vec[0], y = vec[1], z = vec[2];
var len = Math.sqrt(x*x + y*y + z*z);
if (!len) {
dest[0] = 0;
dest[1] = 0;
dest[2] = 0;
return dest;
} else if (len == 1) {
dest[0] = x;
dest[1] = y;
dest[2] = z;
return dest;
}
len = 1 / len;
dest[0] = x*len;
dest[1] = y*len;
dest[2] = z*len;
return dest;
};
/*
* vec3.cross
* Generates the cross product of two vec3s
*
* Params:
* vec - vec3, first operand
* vec2 - vec3, second operand
* dest - Optional, vec3 receiving operation result. If not specified result is written to vec
*
* Returns:
* dest if specified, vec otherwise
*/
vec3.cross = function(vec, vec2, dest){
if(!dest) { dest = vec; }
var x = vec[0], y = vec[1], z = vec[2];
var x2 = vec2[0], y2 = vec2[1], z2 = vec2[2];
dest[0] = y*z2 - z*y2;
dest[1] = z*x2 - x*z2;
dest[2] = x*y2 - y*x2;
return dest;
};
/*
* vec3.length
* Caclulates the length of a vec3
*
* Params:
* vec - vec3 to calculate length of
*
* Returns:
* Length of vec
*/
vec3.length = function(vec){
var x = vec[0], y = vec[1], z = vec[2];
return Math.sqrt(x*x + y*y + z*z);
};
/*
* vec3.dot
* Caclulates the dot product of two vec3s
*
* Params:
* vec - vec3, first operand
* vec2 - vec3, second operand
*
* Returns:
* Dot product of vec and vec2
*/
vec3.dot = function(vec, vec2){
return vec[0]*vec2[0] + vec[1]*vec2[1] + vec[2]*vec2[2];
};
/*
* vec3.direction
* Generates a unit vector pointing from one vector to another
*
* Params:
* vec - origin vec3
* vec2 - vec3 to point to
* dest - Optional, vec3 receiving operation result. If not specified result is written to vec
*
* Returns:
* dest if specified, vec otherwise
*/
vec3.direction = function(vec, vec2, dest) {
if(!dest) { dest = vec; }
var x = vec[0] - vec2[0];
var y = vec[1] - vec2[1];
var z = vec[2] - vec2[2];
var len = Math.sqrt(x*x + y*y + z*z);
if (!len) {
dest[0] = 0;
dest[1] = 0;
dest[2] = 0;
return dest;
}
len = 1 / len;
dest[0] = x * len;
dest[1] = y * len;
dest[2] = z * len;
return dest;
};
/*
* vec3.lerp
* Performs a linear interpolation between two vec3
*
* Params:
* vec - vec3, first vector
* vec2 - vec3, second vector
* lerp - interpolation amount between the two inputs
* dest - Optional, vec3 receiving operation result. If not specified result is written to vec
*
* Returns:
* dest if specified, vec otherwise
*/
vec3.lerp = function(vec, vec2, lerp, dest){
if(!dest) { dest = vec; }
dest[0] = vec[0] + lerp * (vec2[0] - vec[0]);
dest[1] = vec[1] + lerp * (vec2[1] - vec[1]);
dest[2] = vec[2] + lerp * (vec2[2] - vec[2]);
return dest;
}
/*
* vec3.str
* Returns a string representation of a vector
*
* Params:
* vec - vec3 to represent as a string
*
* Returns:
* string representation of vec
*/
vec3.str = function(vec) {
return '[' + vec[0] + ', ' + vec[1] + ', ' + vec[2] + ']';
};
/*
* mat3 - 3x3 Matrix
*/
var mat3 = {};
/*
* mat3.create
* Creates a new instance of a mat3 using the default array type
* Any javascript array containing at least 9 numeric elements can serve as a mat3
*
* Params:
* mat - Optional, mat3 containing values to initialize with
*
* Returns:
* New mat3
*/
mat3.create = function(mat) {
var dest = new glMatrixArrayType(9);
if(mat) {
dest[0] = mat[0];
dest[1] = mat[1];
dest[2] = mat[2];
dest[3] = mat[3];
dest[4] = mat[4];
dest[5] = mat[5];
dest[6] = mat[6];
dest[7] = mat[7];
dest[8] = mat[8];
}
return dest;
};
/*
* mat3.set
* Copies the values of one mat3 to another
*
* Params:
* mat - mat3 containing values to copy
* dest - mat3 receiving copied values
*
* Returns:
* dest
*/
mat3.set = function(mat, dest) {
dest[0] = mat[0];
dest[1] = mat[1];
dest[2] = mat[2];
dest[3] = mat[3];
dest[4] = mat[4];
dest[5] = mat[5];
dest[6] = mat[6];
dest[7] = mat[7];
dest[8] = mat[8];
return dest;
};
/*
* mat3.identity
* Sets a mat3 to an identity matrix
*
* Params:
* dest - mat3 to set
*
* Returns:
* dest
*/
mat3.identity = function(dest) {
dest[0] = 1;
dest[1] = 0;
dest[2] = 0;
dest[3] = 0;
dest[4] = 1;
dest[5] = 0;
dest[6] = 0;
dest[7] = 0;
dest[8] = 1;
return dest;
};
/*
* mat4.transpose
* Transposes a mat3 (flips the values over the diagonal)
*
* Params:
* mat - mat3 to transpose
* dest - Optional, mat3 receiving transposed values. If not specified result is written to mat
*
* Returns:
* dest is specified, mat otherwise
*/
mat3.transpose = function(mat, dest) {
// If we are transposing ourselves we can skip a few steps but have to cache some values
if(!dest || mat == dest) {
var a01 = mat[1], a02 = mat[2];
var a12 = mat[5];
mat[1] = mat[3];
mat[2] = mat[6];
mat[3] = a01;
mat[5] = mat[7];
mat[6] = a02;
mat[7] = a12;
return mat;
}
dest[0] = mat[0];
dest[1] = mat[3];
dest[2] = mat[6];
dest[3] = mat[1];
dest[4] = mat[4];
dest[5] = mat[7];
dest[6] = mat[2];
dest[7] = mat[5];
dest[8] = mat[8];
return dest;
};
/*
* mat3.toMat4
* Copies the elements of a mat3 into the upper 3x3 elements of a mat4
*
* Params:
* mat - mat3 containing values to copy
* dest - Optional, mat4 receiving copied values
*
* Returns:
* dest if specified, a new mat4 otherwise
*/
mat3.toMat4 = function(mat, dest) {
if(!dest) { dest = mat4.create(); }
dest[0] = mat[0];
dest[1] = mat[1];
dest[2] = mat[2];
dest[3] = 0;
dest[4] = mat[3];
dest[5] = mat[4];
dest[6] = mat[5];
dest[7] = 0;
dest[8] = mat[6];
dest[9] = mat[7];
dest[10] = mat[8];
dest[11] = 0;
dest[12] = 0;
dest[13] = 0;
dest[14] = 0;
dest[15] = 1;
return dest;
}
/*
* mat3.str
* Returns a string representation of a mat3
*
* Params:
* mat - mat3 to represent as a string
*
* Returns:
* string representation of mat
*/
mat3.str = function(mat) {
return '[' + mat[0] + ', ' + mat[1] + ', ' + mat[2] +
', ' + mat[3] + ', '+ mat[4] + ', ' + mat[5] +
', ' + mat[6] + ', ' + mat[7] + ', '+ mat[8] + ']';
};
/*
* mat4 - 4x4 Matrix
*/
var mat4 = {};
/*
* mat4.create
* Creates a new instance of a mat4 using the default array type
* Any javascript array containing at least 16 numeric elements can serve as a mat4
*
* Params:
* mat - Optional, mat4 containing values to initialize with
*
* Returns:
* New mat4
*/
mat4.create = function(mat) {
var dest = new glMatrixArrayType(16);
if(mat) {
dest[0] = mat[0];
dest[1] = mat[1];
dest[2] = mat[2];
dest[3] = mat[3];
dest[4] = mat[4];
dest[5] = mat[5];
dest[6] = mat[6];
dest[7] = mat[7];
dest[8] = mat[8];
dest[9] = mat[9];
dest[10] = mat[10];
dest[11] = mat[11];
dest[12] = mat[12];
dest[13] = mat[13];
dest[14] = mat[14];
dest[15] = mat[15];
}
return dest;
};
/*
* mat4.set
* Copies the values of one mat4 to another
*
* Params:
* mat - mat4 containing values to copy
* dest - mat4 receiving copied values
*
* Returns:
* dest
*/
mat4.set = function(mat, dest) {
dest[0] = mat[0];
dest[1] = mat[1];
dest[2] = mat[2];
dest[3] = mat[3];
dest[4] = mat[4];
dest[5] = mat[5];
dest[6] = mat[6];
dest[7] = mat[7];
dest[8] = mat[8];
dest[9] = mat[9];
dest[10] = mat[10];
dest[11] = mat[11];
dest[12] = mat[12];
dest[13] = mat[13];
dest[14] = mat[14];
dest[15] = mat[15];
return dest;
};
/*
* mat4.identity
* Sets a mat4 to an identity matrix
*
* Params:
* dest - mat4 to set
*
* Returns:
* dest
*/
mat4.identity = function(dest) {
dest[0] = 1;
dest[1] = 0;
dest[2] = 0;
dest[3] = 0;
dest[4] = 0;
dest[5] = 1;
dest[6] = 0;
dest[7] = 0;
dest[8] = 0;
dest[9] = 0;
dest[10] = 1;
dest[11] = 0;
dest[12] = 0;
dest[13] = 0;
dest[14] = 0;
dest[15] = 1;
return dest;
};
/*
* mat4.transpose
* Transposes a mat4 (flips the values over the diagonal)
*
* Params:
* mat - mat4 to transpose
* dest - Optional, mat4 receiving transposed values. If not specified result is written to mat
*
* Returns:
* dest is specified, mat otherwise
*/
mat4.transpose = function(mat, dest) {
// If we are transposing ourselves we can skip a few steps but have to cache some values
if(!dest || mat == dest) {
var a01 = mat[1], a02 = mat[2], a03 = mat[3];
var a12 = mat[6], a13 = mat[7];
var a23 = mat[11];
mat[1] = mat[4];
mat[2] = mat[8];
mat[3] = mat[12];
mat[4] = a01;
mat[6] = mat[9];
mat[7] = mat[13];
mat[8] = a02;
mat[9] = a12;
mat[11] = mat[14];
mat[12] = a03;
mat[13] = a13;
mat[14] = a23;
return mat;
}
dest[0] = mat[0];
dest[1] = mat[4];
dest[2] = mat[8];
dest[3] = mat[12];
dest[4] = mat[1];
dest[5] = mat[5];
dest[6] = mat[9];
dest[7] = mat[13];
dest[8] = mat[2];
dest[9] = mat[6];
dest[10] = mat[10];
dest[11] = mat[14];
dest[12] = mat[3];
dest[13] = mat[7];
dest[14] = mat[11];
dest[15] = mat[15];
return dest;
};
/*
* mat4.determinant
* Calculates the determinant of a mat4
*
* Params:
* mat - mat4 to calculate determinant of
*
* Returns:
* determinant of mat
*/
mat4.determinant = function(mat) {
// Cache the matrix values (makes for huge speed increases!)
var a00 = mat[0], a01 = mat[1], a02 = mat[2], a03 = mat[3];
var a10 = mat[4], a11 = mat[5], a12 = mat[6], a13 = mat[7];
var a20 = mat[8], a21 = mat[9], a22 = mat[10], a23 = mat[11];
var a30 = mat[12], a31 = mat[13], a32 = mat[14], a33 = mat[15];
return a30*a21*a12*a03 - a20*a31*a12*a03 - a30*a11*a22*a03 + a10*a31*a22*a03 +
a20*a11*a32*a03 - a10*a21*a32*a03 - a30*a21*a02*a13 + a20*a31*a02*a13 +
a30*a01*a22*a13 - a00*a31*a22*a13 - a20*a01*a32*a13 + a00*a21*a32*a13 +
a30*a11*a02*a23 - a10*a31*a02*a23 - a30*a01*a12*a23 + a00*a31*a12*a23 +
a10*a01*a32*a23 - a00*a11*a32*a23 - a20*a11*a02*a33 + a10*a21*a02*a33 +
a20*a01*a12*a33 - a00*a21*a12*a33 - a10*a01*a22*a33 + a00*a11*a22*a33;
};
/*
* mat4.inverse
* Calculates the inverse matrix of a mat4
*
* Params:
* mat - mat4 to calculate inverse of
* dest - Optional, mat4 receiving inverse matrix. If not specified result is written to mat
*
* Returns:
* dest is specified, mat otherwise
*/
mat4.inverse = function(mat, dest) {
if(!dest) { dest = mat; }
// Cache the matrix values (makes for huge speed increases!)
var a00 = mat[0], a01 = mat[1], a02 = mat[2], a03 = mat[3];
var a10 = mat[4], a11 = mat[5], a12 = mat[6], a13 = mat[7];
var a20 = mat[8], a21 = mat[9], a22 = mat[10], a23 = mat[11];
var a30 = mat[12], a31 = mat[13], a32 = mat[14], a33 = mat[15];
var b00 = a00*a11 - a01*a10;
var b01 = a00*a12 - a02*a10;
var b02 = a00*a13 - a03*a10;
var b03 = a01*a12 - a02*a11;
var b04 = a01*a13 - a03*a11;
var b05 = a02*a13 - a03*a12;
var b06 = a20*a31 - a21*a30;
var b07 = a20*a32 - a22*a30;
var b08 = a20*a33 - a23*a30;
var b09 = a21*a32 - a22*a31;
var b10 = a21*a33 - a23*a31;
var b11 = a22*a33 - a23*a32;
// Calculate the determinant (inlined to avoid double-caching)
var invDet = 1/(b00*b11 - b01*b10 + b02*b09 + b03*b08 - b04*b07 + b05*b06);
dest[0] = (a11*b11 - a12*b10 + a13*b09)*invDet;
dest[1] = (-a01*b11 + a02*b10 - a03*b09)*invDet;
dest[2] = (a31*b05 - a32*b04 + a33*b03)*invDet;
dest[3] = (-a21*b05 + a22*b04 - a23*b03)*invDet;
dest[4] = (-a10*b11 + a12*b08 - a13*b07)*invDet;
dest[5] = (a00*b11 - a02*b08 + a03*b07)*invDet;
dest[6] = (-a30*b05 + a32*b02 - a33*b01)*invDet;
dest[7] = (a20*b05 - a22*b02 + a23*b01)*invDet;
dest[8] = (a10*b10 - a11*b08 + a13*b06)*invDet;
dest[9] = (-a00*b10 + a01*b08 - a03*b06)*invDet;
dest[10] = (a30*b04 - a31*b02 + a33*b00)*invDet;
dest[11] = (-a20*b04 + a21*b02 - a23*b00)*invDet;
dest[12] = (-a10*b09 + a11*b07 - a12*b06)*invDet;
dest[13] = (a00*b09 - a01*b07 + a02*b06)*invDet;
dest[14] = (-a30*b03 + a31*b01 - a32*b00)*invDet;
dest[15] = (a20*b03 - a21*b01 + a22*b00)*invDet;
return dest;
};
/*
* mat4.toRotationMat
* Copies the upper 3x3 elements of a mat4 into another mat4
*
* Params:
* mat - mat4 containing values to copy
* dest - Optional, mat4 receiving copied values
*
* Returns:
* dest is specified, a new mat4 otherwise
*/
mat4.toRotationMat = function(mat, dest) {
if(!dest) { dest = mat4.create(); }
dest[0] = mat[0];
dest[1] = mat[1];
dest[2] = mat[2];
dest[3] = mat[3];
dest[4] = mat[4];
dest[5] = mat[5];
dest[6] = mat[6];
dest[7] = mat[7];
dest[8] = mat[8];
dest[9] = mat[9];
dest[10] = mat[10];
dest[11] = mat[11];
dest[12] = 0;
dest[13] = 0;
dest[14] = 0;
dest[15] = 1;
return dest;
};
/*
* mat4.toMat3
* Copies the upper 3x3 elements of a mat4 into a mat3
*
* Params:
* mat - mat4 containing values to copy
* dest - Optional, mat3 receiving copied values
*
* Returns:
* dest is specified, a new mat3 otherwise
*/
mat4.toMat3 = function(mat, dest) {
if(!dest) { dest = mat3.create(); }
dest[0] = mat[0];
dest[1] = mat[1];
dest[2] = mat[2];
dest[3] = mat[4];
dest[4] = mat[5];
dest[5] = mat[6];
dest[6] = mat[8];
dest[7] = mat[9];
dest[8] = mat[10];
return dest;
};
/*
* mat4.toInverseMat3
* Calculates the inverse of the upper 3x3 elements of a mat4 and copies the result into a mat3
* The resulting matrix is useful for calculating transformed normals
*
* Params:
* mat - mat4 containing values to invert and copy
* dest - Optional, mat3 receiving values
*
* Returns:
* dest is specified, a new mat3 otherwise
*/
mat4.toInverseMat3 = function(mat, dest) {
// Cache the matrix values (makes for huge speed increases!)
var a00 = mat[0], a01 = mat[1], a02 = mat[2];
var a10 = mat[4], a11 = mat[5], a12 = mat[6];
var a20 = mat[8], a21 = mat[9], a22 = mat[10];
var b01 = a22*a11-a12*a21;
var b11 = -a22*a10+a12*a20;
var b21 = a21*a10-a11*a20;
var d = a00*b01 + a01*b11 + a02*b21;
if (!d) { return null; }
var id = 1/d;
if(!dest) { dest = mat3.create(); }
dest[0] = b01*id;
dest[1] = (-a22*a01 + a02*a21)*id;
dest[2] = (a12*a01 - a02*a11)*id;
dest[3] = b11*id;
dest[4] = (a22*a00 - a02*a20)*id;
dest[5] = (-a12*a00 + a02*a10)*id;
dest[6] = b21*id;
dest[7] = (-a21*a00 + a01*a20)*id;
dest[8] = (a11*a00 - a01*a10)*id;
return dest;
};
/*
* mat4.multiply
* Performs a matrix multiplication
*
* Params:
* mat - mat4, first operand
* mat2 - mat4, second operand
* dest - Optional, mat4 receiving operation result. If not specified result is written to mat
*
* Returns:
* dest if specified, mat otherwise
*/
mat4.multiply = function(mat, mat2, dest) {
if(!dest) { dest = mat }
// Cache the matrix values (makes for huge speed increases!)
var a00 = mat[0], a01 = mat[1], a02 = mat[2], a03 = mat[3];
var a10 = mat[4], a11 = mat[5], a12 = mat[6], a13 = mat[7];
var a20 = mat[8], a21 = mat[9], a22 = mat[10], a23 = mat[11];
var a30 = mat[12], a31 = mat[13], a32 = mat[14], a33 = mat[15];
var b00 = mat2[0], b01 = mat2[1], b02 = mat2[2], b03 = mat2[3];
var b10 = mat2[4], b11 = mat2[5], b12 = mat2[6], b13 = mat2[7];
var b20 = mat2[8], b21 = mat2[9], b22 = mat2[10], b23 = mat2[11];
var b30 = mat2[12], b31 = mat2[13], b32 = mat2[14], b33 = mat2[15];
dest[0] = b00*a00 + b01*a10 + b02*a20 + b03*a30;
dest[1] = b00*a01 + b01*a11 + b02*a21 + b03*a31;
dest[2] = b00*a02 + b01*a12 + b02*a22 + b03*a32;
dest[3] = b00*a03 + b01*a13 + b02*a23 + b03*a33;
dest[4] = b10*a00 + b11*a10 + b12*a20 + b13*a30;
dest[5] = b10*a01 + b11*a11 + b12*a21 + b13*a31;
dest[6] = b10*a02 + b11*a12 + b12*a22 + b13*a32;
dest[7] = b10*a03 + b11*a13 + b12*a23 + b13*a33;
dest[8] = b20*a00 + b21*a10 + b22*a20 + b23*a30;
dest[9] = b20*a01 + b21*a11 + b22*a21 + b23*a31;
dest[10] = b20*a02 + b21*a12 + b22*a22 + b23*a32;
dest[11] = b20*a03 + b21*a13 + b22*a23 + b23*a33;
dest[12] = b30*a00 + b31*a10 + b32*a20 + b33*a30;
dest[13] = b30*a01 + b31*a11 + b32*a21 + b33*a31;
dest[14] = b30*a02 + b31*a12 + b32*a22 + b33*a32;
dest[15] = b30*a03 + b31*a13 + b32*a23 + b33*a33;
return dest;
};
/*
* mat4.multiplyVec3
* Transforms a vec3 with the given matrix
* 4th vector component is implicitly '1'
*
* Params:
* mat - mat4 to transform the vector with
* vec - vec3 to transform
* dest - Optional, vec3 receiving operation result. If not specified result is written to vec
*
* Returns:
* dest if specified, vec otherwise
*/
mat4.multiplyVec3 = function(mat, vec, dest) {
if(!dest) { dest = vec }
var x = vec[0], y = vec[1], z = vec[2];
dest[0] = mat[0]*x + mat[4]*y + mat[8]*z + mat[12];
dest[1] = mat[1]*x + mat[5]*y + mat[9]*z + mat[13];
dest[2] = mat[2]*x + mat[6]*y + mat[10]*z + mat[14];
return dest;
};
/*
* mat4.multiplyVec4
* Transforms a vec4 with the given matrix
*
* Params:
* mat - mat4 to transform the vector with
* vec - vec4 to transform
* dest - Optional, vec4 receiving operation result. If not specified result is written to vec
*
* Returns:
* dest if specified, vec otherwise
*/
mat4.multiplyVec4 = function(mat, vec, dest) {
if(!dest) { dest = vec }
var x = vec[0], y = vec[1], z = vec[2], w = vec[3];
dest[0] = mat[0]*x + mat[4]*y + mat[8]*z + mat[12]*w;
dest[1] = mat[1]*x + mat[5]*y + mat[9]*z + mat[13]*w;
dest[2] = mat[2]*x + mat[6]*y + mat[10]*z + mat[14]*w;
dest[3] = mat[3]*x + mat[7]*y + mat[11]*z + mat[15]*w;
return dest;
};
/*
* mat4.translate
* Translates a matrix by the given vector
*
* Params:
* mat - mat4 to translate
* vec - vec3 specifying the translation
* dest - Optional, mat4 receiving operation result. If not specified result is written to mat
*
* Returns:
* dest if specified, mat otherwise
*/
mat4.translate = function(mat, vec, dest) {
var x = vec[0], y = vec[1], z = vec[2];
if(!dest || mat == dest) {
mat[12] = mat[0]*x + mat[4]*y + mat[8]*z + mat[12];
mat[13] = mat[1]*x + mat[5]*y + mat[9]*z + mat[13];
mat[14] = mat[2]*x + mat[6]*y + mat[10]*z + mat[14];
mat[15] = mat[3]*x + mat[7]*y + mat[11]*z + mat[15];
return mat;
}
var a00 = mat[0], a01 = mat[1], a02 = mat[2], a03 = mat[3];
var a10 = mat[4], a11 = mat[5], a12 = mat[6], a13 = mat[7];
var a20 = mat[8], a21 = mat[9], a22 = mat[10], a23 = mat[11];
dest[0] = a00;
dest[1] = a01;
dest[2] = a02;
dest[3] = a03;
dest[4] = a10;
dest[5] = a11;
dest[6] = a12;
dest[7] = a13;
dest[8] = a20;
dest[9] = a21;
dest[10] = a22;
dest[11] = a23;
dest[12] = a00*x + a10*y + a20*z + mat[12];
dest[13] = a01*x + a11*y + a21*z + mat[13];
dest[14] = a02*x + a12*y + a22*z + mat[14];
dest[15] = a03*x + a13*y + a23*z + mat[15];
return dest;
};
/*
* mat4.scale
* Scales a matrix by the given vector
*
* Params:
* mat - mat4 to scale
* vec - vec3 specifying the scale for each axis
* dest - Optional, mat4 receiving operation result. If not specified result is written to mat
*
* Returns:
* dest if specified, mat otherwise
*/
mat4.scale = function(mat, vec, dest) {
var x = vec[0], y = vec[1], z = vec[2];
if(!dest || mat == dest) {
mat[0] *= x;
mat[1] *= x;
mat[2] *= x;
mat[3] *= x;
mat[4] *= y;
mat[5] *= y;
mat[6] *= y;
mat[7] *= y;
mat[8] *= z;
mat[9] *= z;
mat[10] *= z;
mat[11] *= z;
return mat;
}
dest[0] = mat[0]*x;
dest[1] = mat[1]*x;
dest[2] = mat[2]*x;
dest[3] = mat[3]*x;
dest[4] = mat[4]*y;
dest[5] = mat[5]*y;
dest[6] = mat[6]*y;
dest[7] = mat[7]*y;
dest[8] = mat[8]*z;
dest[9] = mat[9]*z;
dest[10] = mat[10]*z;
dest[11] = mat[11]*z;
dest[12] = mat[12];
dest[13] = mat[13];
dest[14] = mat[14];
dest[15] = mat[15];
return dest;
};
/*
* mat4.rotate
* Rotates a matrix by the given angle around the specified axis
* If rotating around a primary axis (X,Y,Z) one of the specialized rotation functions should be used instead for performance
*
* Params:
* mat - mat4 to rotate
* angle - angle (in radians) to rotate
* axis - vec3 representing the axis to rotate around
* dest - Optional, mat4 receiving operation result. If not specified result is written to mat
*
* Returns:
* dest if specified, mat otherwise
*/
mat4.rotate = function(mat, angle, axis, dest) {
var x = axis[0], y = axis[1], z = axis[2];
var len = Math.sqrt(x*x + y*y + z*z);
if (!len) { return null; }
if (len != 1) {
len = 1 / len;
x *= len;
y *= len;
z *= len;
}
var s = Math.sin(angle);
var c = Math.cos(angle);
var t = 1-c;
// Cache the matrix values (makes for huge speed increases!)
var a00 = mat[0], a01 = mat[1], a02 = mat[2], a03 = mat[3];
var a10 = mat[4], a11 = mat[5], a12 = mat[6], a13 = mat[7];
var a20 = mat[8], a21 = mat[9], a22 = mat[10], a23 = mat[11];
// Construct the elements of the rotation matrix
var b00 = x*x*t + c, b01 = y*x*t + z*s, b02 = z*x*t - y*s;
var b10 = x*y*t - z*s, b11 = y*y*t + c, b12 = z*y*t + x*s;
var b20 = x*z*t + y*s, b21 = y*z*t - x*s, b22 = z*z*t + c;
if(!dest) {
dest = mat
} else if(mat != dest) { // If the source and destination differ, copy the unchanged last row
dest[12] = mat[12];
dest[13] = mat[13];
dest[14] = mat[14];
dest[15] = mat[15];
}
// Perform rotation-specific matrix multiplication
dest[0] = a00*b00 + a10*b01 + a20*b02;
dest[1] = a01*b00 + a11*b01 + a21*b02;
dest[2] = a02*b00 + a12*b01 + a22*b02;
dest[3] = a03*b00 + a13*b01 + a23*b02;
dest[4] = a00*b10 + a10*b11 + a20*b12;
dest[5] = a01*b10 + a11*b11 + a21*b12;
dest[6] = a02*b10 + a12*b11 + a22*b12;
dest[7] = a03*b10 + a13*b11 + a23*b12;
dest[8] = a00*b20 + a10*b21 + a20*b22;
dest[9] = a01*b20 + a11*b21 + a21*b22;
dest[10] = a02*b20 + a12*b21 + a22*b22;
dest[11] = a03*b20 + a13*b21 + a23*b22;
return dest;
};
/*
* mat4.rotateX
* Rotates a matrix by the given angle around the X axis
*
* Params:
* mat - mat4 to rotate
* angle - angle (in radians) to rotate
* dest - Optional, mat4 receiving operation result. If not specified result is written to mat
*
* Returns:
* dest if specified, mat otherwise
*/
mat4.rotateX = function(mat, angle, dest) {
var s = Math.sin(angle);
var c = Math.cos(angle);
// Cache the matrix values (makes for huge speed increases!)
var a10 = mat[4], a11 = mat[5], a12 = mat[6], a13 = mat[7];
var a20 = mat[8], a21 = mat[9], a22 = mat[10], a23 = mat[11];
if(!dest) {
dest = mat
} else if(mat != dest) { // If the source and destination differ, copy the unchanged rows
dest[0] = mat[0];
dest[1] = mat[1];
dest[2] = mat[2];
dest[3] = mat[3];
dest[12] = mat[12];
dest[13] = mat[13];
dest[14] = mat[14];
dest[15] = mat[15];
}
// Perform axis-specific matrix multiplication
dest[4] = a10*c + a20*s;
dest[5] = a11*c + a21*s;
dest[6] = a12*c + a22*s;
dest[7] = a13*c + a23*s;
dest[8] = a10*-s + a20*c;
dest[9] = a11*-s + a21*c;
dest[10] = a12*-s + a22*c;
dest[11] = a13*-s + a23*c;
return dest;
};
/*
* mat4.rotateY
* Rotates a matrix by the given angle around the Y axis
*
* Params:
* mat - mat4 to rotate
* angle - angle (in radians) to rotate
* dest - Optional, mat4 receiving operation result. If not specified result is written to mat
*
* Returns:
* dest if specified, mat otherwise
*/
mat4.rotateY = function(mat, angle, dest) {
var s = Math.sin(angle);
var c = Math.cos(angle);
// Cache the matrix values (makes for huge speed increases!)
var a00 = mat[0], a01 = mat[1], a02 = mat[2], a03 = mat[3];
var a20 = mat[8], a21 = mat[9], a22 = mat[10], a23 = mat[11];
if(!dest) {
dest = mat
} else if(mat != dest) { // If the source and destination differ, copy the unchanged rows
dest[4] = mat[4];
dest[5] = mat[5];
dest[6] = mat[6];
dest[7] = mat[7];
dest[12] = mat[12];
dest[13] = mat[13];
dest[14] = mat[14];
dest[15] = mat[15];
}
// Perform axis-specific matrix multiplication
dest[0] = a00*c + a20*-s;
dest[1] = a01*c + a21*-s;
dest[2] = a02*c + a22*-s;
dest[3] = a03*c + a23*-s;
dest[8] = a00*s + a20*c;
dest[9] = a01*s + a21*c;
dest[10] = a02*s + a22*c;
dest[11] = a03*s + a23*c;
return dest;
};
/*
* mat4.rotateZ
* Rotates a matrix by the given angle around the Z axis
*
* Params:
* mat - mat4 to rotate
* angle - angle (in radians) to rotate
* dest - Optional, mat4 receiving operation result. If not specified result is written to mat
*
* Returns:
* dest if specified, mat otherwise
*/
mat4.rotateZ = function(mat, angle, dest) {
var s = Math.sin(angle);
var c = Math.cos(angle);
// Cache the matrix values (makes for huge speed increases!)
var a00 = mat[0], a01 = mat[1], a02 = mat[2], a03 = mat[3];
var a10 = mat[4], a11 = mat[5], a12 = mat[6], a13 = mat[7];
if(!dest) {
dest = mat
} else if(mat != dest) { // If the source and destination differ, copy the unchanged last row
dest[8] = mat[8];
dest[9] = mat[9];
dest[10] = mat[10];
dest[11] = mat[11];
dest[12] = mat[12];
dest[13] = mat[13];
dest[14] = mat[14];
dest[15] = mat[15];
}
// Perform axis-specific matrix multiplication
dest[0] = a00*c + a10*s;
dest[1] = a01*c + a11*s;
dest[2] = a02*c + a12*s;
dest[3] = a03*c + a13*s;
dest[4] = a00*-s + a10*c;
dest[5] = a01*-s + a11*c;
dest[6] = a02*-s + a12*c;
dest[7] = a03*-s + a13*c;
return dest;
};
/*
* mat4.frustum
* Generates a frustum matrix with the given bounds
*
* Params:
* left, right - scalar, left and right bounds of the frustum
* bottom, top - scalar, bottom and top bounds of the frustum
* near, far - scalar, near and far bounds of the frustum
* dest - Optional, mat4 frustum matrix will be written into
*
* Returns:
* dest if specified, a new mat4 otherwise
*/
mat4.frustum = function(left, right, bottom, top, near, far, dest) {
if(!dest) { dest = mat4.create(); }
var rl = (right - left);
var tb = (top - bottom);
var fn = (far - near);
dest[0] = (near*2) / rl;
dest[1] = 0;
dest[2] = 0;
dest[3] = 0;
dest[4] = 0;
dest[5] = (near*2) / tb;
dest[6] = 0;
dest[7] = 0;
dest[8] = (right + left) / rl;
dest[9] = (top + bottom) / tb;
dest[10] = -(far + near) / fn;
dest[11] = -1;
dest[12] = 0;
dest[13] = 0;
dest[14] = -(far*near*2) / fn;
dest[15] = 0;
return dest;
};
/*
* mat4.perspective
* Generates a perspective projection matrix with the given bounds
*
* Params:
* fovy - scalar, vertical field of view
* aspect - scalar, aspect ratio. typically viewport width/height
* near, far - scalar, near and far bounds of the frustum
* dest - Optional, mat4 frustum matrix will be written into
*
* Returns:
* dest if specified, a new mat4 otherwise
*/
mat4.perspective = function(fovy, aspect, near, far, dest) {
var top = near*Math.tan(fovy*Math.PI / 360.0);
var right = top*aspect;
return mat4.frustum(-right, right, -top, top, near, far, dest);
};
/*
* mat4.ortho
* Generates a orthogonal projection matrix with the given bounds
*
* Params:
* left, right - scalar, left and right bounds of the frustum
* bottom, top - scalar, bottom and top bounds of the frustum
* near, far - scalar, near and far bounds of the frustum
* dest - Optional, mat4 frustum matrix will be written into
*
* Returns:
* dest if specified, a new mat4 otherwise
*/
mat4.ortho = function(left, right, bottom, top, near, far, dest) {
if(!dest) { dest = mat4.create(); }
var rl = (right - left);
var tb = (top - bottom);
var fn = (far - near);
dest[0] = 2 / rl;
dest[1] = 0;
dest[2] = 0;
dest[3] = 0;
dest[4] = 0;
dest[5] = 2 / tb;
dest[6] = 0;
dest[7] = 0;
dest[8] = 0;
dest[9] = 0;
dest[10] = -2 / fn;
dest[11] = 0;
dest[12] = -(left + right) / rl;
dest[13] = -(top + bottom) / tb;
dest[14] = -(far + near) / fn;
dest[15] = 1;
return dest;
};
/*
* mat4.ortho
* Generates a look-at matrix with the given eye position, focal point, and up axis
*
* Params:
* eye - vec3, position of the viewer
* center - vec3, point the viewer is looking at
* up - vec3 pointing "up"
* dest - Optional, mat4 frustum matrix will be written into
*
* Returns:
* dest if specified, a new mat4 otherwise
*/
mat4.lookAt = function(eye, center, up, dest) {
if(!dest) { dest = mat4.create(); }
var eyex = eye[0],
eyey = eye[1],
eyez = eye[2],
upx = up[0],
upy = up[1],
upz = up[2],
centerx = center[0],
centery = center[1],
centerz = center[2];
if (eyex == centerx && eyey == centery && eyez == centerz) {
return mat4.identity(dest);
}
var z0,z1,z2,x0,x1,x2,y0,y1,y2,len;
//vec3.direction(eye, center, z);
z0 = eyex - center[0];
z1 = eyey - center[1];
z2 = eyez - center[2];
// normalize (no check needed for 0 because of early return)
len = 1/Math.sqrt(z0*z0 + z1*z1 + z2*z2);
z0 *= len;
z1 *= len;
z2 *= len;
//vec3.normalize(vec3.cross(up, z, x));
x0 = upy*z2 - upz*z1;
x1 = upz*z0 - upx*z2;
x2 = upx*z1 - upy*z0;
len = Math.sqrt(x0*x0 + x1*x1 + x2*x2);
if (!len) {
x0 = 0;
x1 = 0;
x2 = 0;
} else {
len = 1/len;
x0 *= len;
x1 *= len;
x2 *= len;
};
//vec3.normalize(vec3.cross(z, x, y));
y0 = z1*x2 - z2*x1;
y1 = z2*x0 - z0*x2;
y2 = z0*x1 - z1*x0;
len = Math.sqrt(y0*y0 + y1*y1 + y2*y2);
if (!len) {
y0 = 0;
y1 = 0;
y2 = 0;
} else {
len = 1/len;
y0 *= len;
y1 *= len;
y2 *= len;
}
dest[0] = x0;
dest[1] = y0;
dest[2] = z0;
dest[3] = 0;
dest[4] = x1;
dest[5] = y1;
dest[6] = z1;
dest[7] = 0;
dest[8] = x2;
dest[9] = y2;
dest[10] = z2;
dest[11] = 0;
dest[12] = -(x0*eyex + x1*eyey + x2*eyez);
dest[13] = -(y0*eyex + y1*eyey + y2*eyez);
dest[14] = -(z0*eyex + z1*eyey + z2*eyez);
dest[15] = 1;
return dest;
};
/*
* mat4.str
* Returns a string representation of a mat4
*
* Params:
* mat - mat4 to represent as a string
*
* Returns:
* string representation of mat
*/
mat4.str = function(mat) {
return '[' + mat[0] + ', ' + mat[1] + ', ' + mat[2] + ', ' + mat[3] +
', '+ mat[4] + ', ' + mat[5] + ', ' + mat[6] + ', ' + mat[7] +
', '+ mat[8] + ', ' + mat[9] + ', ' + mat[10] + ', ' + mat[11] +
', '+ mat[12] + ', ' + mat[13] + ', ' + mat[14] + ', ' + mat[15] + ']';
};
/*
* quat4 - Quaternions
*/
quat4 = {};
/*
* quat4.create
* Creates a new instance of a quat4 using the default array type
* Any javascript array containing at least 4 numeric elements can serve as a quat4
*
* Params:
* quat - Optional, quat4 containing values to initialize with
*
* Returns:
* New quat4
*/
quat4.create = function(quat) {
var dest = new glMatrixArrayType(4);
if(quat) {
dest[0] = quat[0];
dest[1] = quat[1];
dest[2] = quat[2];
dest[3] = quat[3];
}
return dest;
};
/*
* quat4.set
* Copies the values of one quat4 to another
*
* Params:
* quat - quat4 containing values to copy
* dest - quat4 receiving copied values
*
* Returns:
* dest
*/
quat4.set = function(quat, dest) {
dest[0] = quat[0];
dest[1] = quat[1];
dest[2] = quat[2];
dest[3] = quat[3];
return dest;
};
/*
* quat4.calculateW
* Calculates the W component of a quat4 from the X, Y, and Z components.
* Assumes that quaternion is 1 unit in length.
* Any existing W component will be ignored.
*
* Params:
* quat - quat4 to calculate W component of
* dest - Optional, quat4 receiving calculated values. If not specified result is written to quat
*
* Returns:
* dest if specified, quat otherwise
*/
quat4.calculateW = function(quat, dest) {
var x = quat[0], y = quat[1], z = quat[2];
if(!dest || quat == dest) {
quat[3] = -Math.sqrt(Math.abs(1.0 - x*x - y*y - z*z));
return quat;
}
dest[0] = x;
dest[1] = y;
dest[2] = z;
dest[3] = -Math.sqrt(Math.abs(1.0 - x*x - y*y - z*z));
return dest;
}
/*
* quat4.inverse
* Calculates the inverse of a quat4
*
* Params:
* quat - quat4 to calculate inverse of
* dest - Optional, quat4 receiving inverse values. If not specified result is written to quat
*
* Returns:
* dest if specified, quat otherwise
*/
quat4.inverse = function(quat, dest) {
if(!dest || quat == dest) {
quat[0] *= -1;
quat[1] *= -1;
quat[2] *= -1;
return quat;
}
dest[0] = -quat[0];
dest[1] = -quat[1];
dest[2] = -quat[2];
dest[3] = quat[3];
return dest;
}
/*
* quat4.length
* Calculates the length of a quat4
*
* Params:
* quat - quat4 to calculate length of
*
* Returns:
* Length of quat
*/
quat4.length = function(quat) {
var x = quat[0], y = quat[1], z = quat[2], w = quat[3];
return Math.sqrt(x*x + y*y + z*z + w*w);
}
/*
* quat4.normalize
* Generates a unit quaternion of the same direction as the provided quat4
* If quaternion length is 0, returns [0, 0, 0, 0]
*
* Params:
* quat - quat4 to normalize
* dest - Optional, quat4 receiving operation result. If not specified result is written to quat
*
* Returns:
* dest if specified, quat otherwise
*/
quat4.normalize = function(quat, dest) {
if(!dest) { dest = quat; }
var x = quat[0], y = quat[1], z = quat[2], w = quat[3];
var len = Math.sqrt(x*x + y*y + z*z + w*w);
if(len == 0) {
dest[0] = 0;
dest[1] = 0;
dest[2] = 0;
dest[3] = 0;
return dest;
}
len = 1/len;
dest[0] = x * len;
dest[1] = y * len;
dest[2] = z * len;
dest[3] = w * len;
return dest;
}
/*
* quat4.multiply
* Performs a quaternion multiplication
*
* Params:
* quat - quat4, first operand
* quat2 - quat4, second operand
* dest - Optional, quat4 receiving operation result. If not specified result is written to quat
*
* Returns:
* dest if specified, quat otherwise
*/
quat4.multiply = function(quat, quat2, dest) {
if(!dest) { dest = quat; }
var qax = quat[0], qay = quat[1], qaz = quat[2], qaw = quat[3];
var qbx = quat2[0], qby = quat2[1], qbz = quat2[2], qbw = quat2[3];
dest[0] = qax*qbw + qaw*qbx + qay*qbz - qaz*qby;
dest[1] = qay*qbw + qaw*qby + qaz*qbx - qax*qbz;
dest[2] = qaz*qbw + qaw*qbz + qax*qby - qay*qbx;
dest[3] = qaw*qbw - qax*qbx - qay*qby - qaz*qbz;
return dest;
}
/*
* quat4.multiplyVec3
* Transforms a vec3 with the given quaternion
*
* Params:
* quat - quat4 to transform the vector with
* vec - vec3 to transform
* dest - Optional, vec3 receiving operation result. If not specified result is written to vec
*
* Returns:
* dest if specified, vec otherwise
*/
quat4.multiplyVec3 = function(quat, vec, dest) {
if(!dest) { dest = vec; }
var x = vec[0], y = vec[1], z = vec[2];
var qx = quat[0], qy = quat[1], qz = quat[2], qw = quat[3];
// calculate quat * vec
var ix = qw*x + qy*z - qz*y;
var iy = qw*y + qz*x - qx*z;
var iz = qw*z + qx*y - qy*x;
var iw = -qx*x - qy*y - qz*z;
// calculate result * inverse quat
dest[0] = ix*qw + iw*-qx + iy*-qz - iz*-qy;
dest[1] = iy*qw + iw*-qy + iz*-qx - ix*-qz;
dest[2] = iz*qw + iw*-qz + ix*-qy - iy*-qx;
return dest;
}
/*
* quat4.toMat3
* Calculates a 3x3 matrix from the given quat4
*
* Params:
* quat - quat4 to create matrix from
* dest - Optional, mat3 receiving operation result
*
* Returns:
* dest if specified, a new mat3 otherwise
*/
quat4.toMat3 = function(quat, dest) {
if(!dest) { dest = mat3.create(); }
var x = quat[0], y = quat[1], z = quat[2], w = quat[3];
var x2 = x + x;
var y2 = y + y;
var z2 = z + z;
var xx = x*x2;
var xy = x*y2;
var xz = x*z2;
var yy = y*y2;
var yz = y*z2;
var zz = z*z2;
var wx = w*x2;
var wy = w*y2;
var wz = w*z2;
dest[0] = 1 - (yy + zz);
dest[1] = xy - wz;
dest[2] = xz + wy;
dest[3] = xy + wz;
dest[4] = 1 - (xx + zz);
dest[5] = yz - wx;
dest[6] = xz - wy;
dest[7] = yz + wx;
dest[8] = 1 - (xx + yy);
return dest;
}
/*
* quat4.toMat4
* Calculates a 4x4 matrix from the given quat4
*
* Params:
* quat - quat4 to create matrix from
* dest - Optional, mat4 receiving operation result
*
* Returns:
* dest if specified, a new mat4 otherwise
*/
quat4.toMat4 = function(quat, dest) {
if(!dest) { dest = mat4.create(); }
var x = quat[0], y = quat[1], z = quat[2], w = quat[3];
var x2 = x + x;
var y2 = y + y;
var z2 = z + z;
var xx = x*x2;
var xy = x*y2;
var xz = x*z2;
var yy = y*y2;
var yz = y*z2;
var zz = z*z2;
var wx = w*x2;
var wy = w*y2;
var wz = w*z2;
dest[0] = 1 - (yy + zz);
dest[1] = xy - wz;
dest[2] = xz + wy;
dest[3] = 0;
dest[4] = xy + wz;
dest[5] = 1 - (xx + zz);
dest[6] = yz - wx;
dest[7] = 0;
dest[8] = xz - wy;
dest[9] = yz + wx;
dest[10] = 1 - (xx + yy);
dest[11] = 0;
dest[12] = 0;
dest[13] = 0;
dest[14] = 0;
dest[15] = 1;
return dest;
}
/*
* quat4.slerp
* Performs a spherical linear interpolation between two quat4
*
* Params:
* quat - quat4, first quaternion
* quat2 - quat4, second quaternion
* slerp - interpolation amount between the two inputs
* dest - Optional, quat4 receiving operation result. If not specified result is written to quat
*
* Returns:
* dest if specified, quat otherwise
*/
quat4.slerp = function(quat, quat2, slerp, dest) {
if(!dest) { dest = quat; }
var cosHalfTheta = quat[0]*quat2[0] + quat[1]*quat2[1] + quat[2]*quat2[2] + quat[3]*quat2[3];
if (Math.abs(cosHalfTheta) >= 1.0){
if(dest != quat) {
dest[0] = quat[0];
dest[1] = quat[1];
dest[2] = quat[2];
dest[3] = quat[3];
}
return dest;
}
var halfTheta = Math.acos(cosHalfTheta);
var sinHalfTheta = Math.sqrt(1.0 - cosHalfTheta*cosHalfTheta);
if (Math.abs(sinHalfTheta) < 0.001){
dest[0] = (quat[0]*0.5 + quat2[0]*0.5);
dest[1] = (quat[1]*0.5 + quat2[1]*0.5);
dest[2] = (quat[2]*0.5 + quat2[2]*0.5);
dest[3] = (quat[3]*0.5 + quat2[3]*0.5);
return dest;
}
var ratioA = Math.sin((1 - slerp)*halfTheta) / sinHalfTheta;
var ratioB = Math.sin(slerp*halfTheta) / sinHalfTheta;
dest[0] = (quat[0]*ratioA + quat2[0]*ratioB);
dest[1] = (quat[1]*ratioA + quat2[1]*ratioB);
dest[2] = (quat[2]*ratioA + quat2[2]*ratioB);
dest[3] = (quat[3]*ratioA + quat2[3]*ratioB);
return dest;
}
/*
* quat4.str
* Returns a string representation of a quaternion
*
* Params:
* quat - quat4 to represent as a string
*
* Returns:
* string representation of quat
*/
quat4.str = function(quat) {
return '[' + quat[0] + ', ' + quat[1] + ', ' + quat[2] + ', ' + quat[3] + ']';
}