glMatrix-0.9.5.min.js

// glMatrix v0.9.5
glMatrixArrayType = typeof Float32Array != "undefined" ? Float32Array : typeof WebGLFloatArray != "undefined" ? WebGLFloatArray : Array;
var vec3 = {};
vec3.create = function(a) {
    var b = new glMatrixArrayType(3);
    if (a) {
        b[0] = a[0];
        b[1] = a[1];
        b[2] = a[2]
    }
    return b
};
vec3.set = function(a, b) {
    b[0] = a[0];
    b[1] = a[1];
    b[2] = a[2];
    return b
};
vec3.add = function(a, b, c) {
    if (!c || a == c) {
        a[0] += b[0];
        a[1] += b[1];
        a[2] += b[2];
        return a
    }
    c[0] = a[0] + b[0];
    c[1] = a[1] + b[1];
    c[2] = a[2] + b[2];
    return c
};
vec3.subtract = function(a, b, c) {
    if (!c || a == c) {
        a[0] -= b[0];
        a[1] -= b[1];
        a[2] -= b[2];
        return a
    }
    c[0] = a[0] - b[0];
    c[1] = a[1] - b[1];
    c[2] = a[2] - b[2];
    return c
};
vec3.negate = function(a, b) {
    b || (b = a);
    b[0] =- a[0];
    b[1] =- a[1];
    b[2] =- a[2];
    return b
};
vec3.scale = function(a, b, c) {
    if (!c || a == c) {
        a[0]*=b;
        a[1]*=b;
        a[2]*=b;
        return a
    }
    c[0] = a[0] * b;
    c[1] = a[1] * b;
    c[2] = a[2] * b;
    return c
};
vec3.normalize = function(a, b) {
    b || (b = a);
    var c = a[0], d = a[1], e = a[2], g = Math.sqrt(c * c + d * d + e * e);
    if (g) {
        if (g == 1) {
            b[0] = c;
            b[1] = d;
            b[2] = e;
            return b
        }
    } else {
        b[0] = 0;
        b[1] = 0;
        b[2] = 0;
        return b
    }
    g = 1 / g;
    b[0] = c * g;
    b[1] = d * g;
    b[2] = e * g;
    return b
};
vec3.cross = function(a, b, c) {
    c || (c = a);
    var d = a[0], e = a[1];
    a = a[2];
    var g = b[0], f = b[1];
    b = b[2];
    c[0] = e * b - a * f;
    c[1] = a * g - d * b;
    c[2] = d * f - e * g;
    return c
};
vec3.length = function(a) {
    var b = a[0], c = a[1];
    a = a[2];
    return Math.sqrt(b * b + c * c + a * a)
};
vec3.dot = function(a, b) {
    return a[0] * b[0] + a[1] * b[1] + a[2] * b[2]
};
vec3.direction = function(a, b, c) {
    c || (c = a);
    var d = a[0] - b[0], e = a[1] - b[1];
    a = a[2] - b[2];
    b = Math.sqrt(d * d + e * e + a * a);
    if (!b) {
        c[0] = 0;
        c[1] = 0;
        c[2] = 0;
        return c
    }
    b = 1 / b;
    c[0] = d * b;
    c[1] = e * b;
    c[2] = a * b;
    return c
};
vec3.lerp = function(a, b, c, d) {
    d || (d = a);
    d[0] = a[0] + c * (b[0] - a[0]);
    d[1] = a[1] + c * (b[1] - a[1]);
    d[2] = a[2] + c * (b[2] - a[2]);
    return d
};
vec3.str = function(a) {
    return "[" + a[0] + ", " + a[1] + ", " + a[2] + "]"
};
var mat3 = {};
mat3.create = function(a) {
    var b = new glMatrixArrayType(9);
    if (a) {
        b[0] = a[0];
        b[1] = a[1];
        b[2] = a[2];
        b[3] = a[3];
        b[4] = a[4];
        b[5] = a[5];
        b[6] = a[6];
        b[7] = a[7];
        b[8] = a[8];
        b[9] = a[9]
    }
    return b
};
mat3.set = function(a, b) {
    b[0] = a[0];
    b[1] = a[1];
    b[2] = a[2];
    b[3] = a[3];
    b[4] = a[4];
    b[5] = a[5];
    b[6] = a[6];
    b[7] = a[7];
    b[8] = a[8];
    return b
};
mat3.identity = function(a) {
    a[0] = 1;
    a[1] = 0;
    a[2] = 0;
    a[3] = 0;
    a[4] = 1;
    a[5] = 0;
    a[6] = 0;
    a[7] = 0;
    a[8] = 1;
    return a
};
mat3.transpose = function(a, b) {
    if (!b || a == b) {
        var c = a[1], d = a[2], e = a[5];
        a[1] = a[3];
        a[2] = a[6];
        a[3] = c;
        a[5] = a[7];
        a[6] = d;
        a[7] = e;
        return a
    }
    b[0] = a[0];
    b[1] = a[3];
    b[2] = a[6];
    b[3] = a[1];
    b[4] = a[4];
    b[5] = a[7];
    b[6] = a[2];
    b[7] = a[5];
    b[8] = a[8];
    return b
};
mat3.toMat4 = function(a, b) {
    b || (b = mat4.create());
    b[0] = a[0];
    b[1] = a[1];
    b[2] = a[2];
    b[3] = 0;
    b[4] = a[3];
    b[5] = a[4];
    b[6] = a[5];
    b[7] = 0;
    b[8] = a[6];
    b[9] = a[7];
    b[10] = a[8];
    b[11] = 0;
    b[12] = 0;
    b[13] = 0;
    b[14] = 0;
    b[15] = 1;
    return b
};
mat3.str = function(a) {
    return "[" + a[0] + ", " + a[1] + ", " + a[2] + ", " + a[3] + ", " + a[4] + ", " + a[5] + ", " + a[6] + ", " + a[7] + ", " + a[8] + "]"
};
var mat4 = {};
mat4.create = function(a) {
    var b = new glMatrixArrayType(16);
    if (a) {
        b[0] = a[0];
        b[1] = a[1];
        b[2] = a[2];
        b[3] = a[3];
        b[4] = a[4];
        b[5] = a[5];
        b[6] = a[6];
        b[7] = a[7];
        b[8] = a[8];
        b[9] = a[9];
        b[10] = a[10];
        b[11] = a[11];
        b[12] = a[12];
        b[13] = a[13];
        b[14] = a[14];
        b[15] = a[15]
    }
    return b
};
mat4.set = function(a, b) {
    b[0] = a[0];
    b[1] = a[1];
    b[2] = a[2];
    b[3] = a[3];
    b[4] = a[4];
    b[5] = a[5];
    b[6] = a[6];
    b[7] = a[7];
    b[8] = a[8];
    b[9] = a[9];
    b[10] = a[10];
    b[11] = a[11];
    b[12] = a[12];
    b[13] = a[13];
    b[14] = a[14];
    b[15] = a[15];
    return b
};
mat4.identity = function(a) {
    a[0] = 1;
    a[1] = 0;
    a[2] = 0;
    a[3] = 0;
    a[4] = 0;
    a[5] = 1;
    a[6] = 0;
    a[7] = 0;
    a[8] = 0;
    a[9] = 0;
    a[10] = 1;
    a[11] = 0;
    a[12] = 0;
    a[13] = 0;
    a[14] = 0;
    a[15] = 1;
    return a
};
mat4.transpose = function(a, b) {
    if (!b || a == b) {
        var c = a[1], d = a[2], e = a[3], g = a[6], f = a[7], h = a[11];
        a[1] = a[4];
        a[2] = a[8];
        a[3] = a[12];
        a[4] = c;
        a[6] = a[9];
        a[7] = a[13];
        a[8] = d;
        a[9] = g;
        a[11] = a[14];
        a[12] = e;
        a[13] = f;
        a[14] = h;
        return a
    }
    b[0] = a[0];
    b[1] = a[4];
    b[2] = a[8];
    b[3] = a[12];
    b[4] = a[1];
    b[5] = a[5];
    b[6] = a[9];
    b[7] = a[13];
    b[8] = a[2];
    b[9] = a[6];
    b[10] = a[10];
    b[11] = a[14];
    b[12] = a[3];
    b[13] = a[7];
    b[14] = a[11];
    b[15] = a[15];
    return b
};
mat4.determinant = function(a) {
    var b = a[0], c = a[1], d = a[2], e = a[3], g = a[4], f = a[5], h = a[6], i = a[7], j = a[8], k = a[9], l = a[10], o = a[11], m = a[12], n = a[13], p = a[14];
    a = a[15];
    return m * k * h * e - j * n * h * e - m * f * l * e + g * n * l * e + j * f * p * e - g * k * p * e - m * k * d * i + j * n * d * i + m * c * l * i - b * n * l * i - j * c * p * i + b * k * p * i + m * f * d * o - g * n * d * o - m * c * h * o + b * n * h * o + g * c * p * o - b * f * p * o - j * f * d * a + g * k * d * a + j * c * h * a - b * k * h * a - g * c * l * a + b * f * l * a
};
mat4.inverse = function(a, b) {
    b || (b = a);
    var c = a[0], d = a[1], e = a[2], g = a[3], f = a[4], h = a[5], i = a[6], j = a[7], k = a[8], l = a[9], o = a[10], m = a[11], n = a[12], p = a[13], r = a[14], s = a[15], A = c * h - d * f, B = c * i - e * f, t = c * j - g * f, u = d * i - e * h, v = d * j - g * h, w = e * j - g * i, x = k * p - l * n, y = k * r - o * n, z = k * s - m * n, C = l * r - o * p, D = l * s - m * p, E = o * s - m * r, q = 1 / (A * E - B * D + t * C + u * z - v * y + w * x);
    b[0] = (h * E - i * D + j * C) * q;
    b[1] = ( - d * E + e * D - g * C) * q;
    b[2] = (p * w - r * v + s * u) * q;
    b[3] = ( - l * w + o * v - m * u) * q;
    b[4] = ( - f * E + i * z - j * y) * q;
    b[5] = (c * E - e * z + g * y) * q;
    b[6] = ( - n * w + r * t - s * B) * q;
    b[7] = (k * w - o * t + m * B) * q;
    b[8] = (f * D - h * z + j * x) * q;
    b[9] = ( - c * D + d * z - g * x) * q;
    b[10] = (n * v - p * t + s * A) * q;
    b[11] = ( - k * v + l * t - m * A) * q;
    b[12] = ( - f * C + h * y - i * x) * q;
    b[13] = (c * C - d * y + e * x) * q;
    b[14] = ( - n * u + p * B - r * A) * q;
    b[15] = (k * u - l * B + o * A) * q;
    return b
};
mat4.toRotationMat = function(a, b) {
    b || (b = mat4.create());
    b[0] = a[0];
    b[1] = a[1];
    b[2] = a[2];
    b[3] = a[3];
    b[4] = a[4];
    b[5] = a[5];
    b[6] = a[6];
    b[7] = a[7];
    b[8] = a[8];
    b[9] = a[9];
    b[10] = a[10];
    b[11] = a[11];
    b[12] = 0;
    b[13] = 0;
    b[14] = 0;
    b[15] = 1;
    return b
};
mat4.toMat3 = function(a, b) {
    b || (b = mat3.create());
    b[0] = a[0];
    b[1] = a[1];
    b[2] = a[2];
    b[3] = a[4];
    b[4] = a[5];
    b[5] = a[6];
    b[6] = a[8];
    b[7] = a[9];
    b[8] = a[10];
    return b
};
mat4.toInverseMat3 = function(a, b) {
    var c = a[0], d = a[1], e = a[2], g = a[4], f = a[5], h = a[6], i = a[8], j = a[9], k = a[10], l = k * f - h * j, o =- k * g + h * i, m = j * g - f * i, n = c * l + d * o + e * m;
    if (!n)
        return null;
    n = 1 / n;
    b || (b = mat3.create());
    b[0] = l * n;
    b[1] = ( - k * d + e * j) * n;
    b[2] = (h * d - e * f) * n;
    b[3] = o * n;
    b[4] = (k * c - e * i) * n;
    b[5] = ( - h * c + e * g) * n;
    b[6] = m * n;
    b[7] = ( - j * c + d * i) * n;
    b[8] = (f * c - d * g) * n;
    return b
};
mat4.multiply = function(a, b, c) {
    c || (c = a);
    var d = a[0], e = a[1], g = a[2], f = a[3], h = a[4], i = a[5], j = a[6], k = a[7], l = a[8], o = a[9], m = a[10], n = a[11], p = a[12], r = a[13], s = a[14];
    a = a[15];
    var A = b[0], B = b[1], t = b[2], u = b[3], v = b[4], w = b[5], x = b[6], y = b[7], z = b[8], C = b[9], D = b[10], E = b[11], q = b[12], F = b[13], G = b[14];
    b = b[15];
    c[0] = A * d + B * h + t * l + u * p;
    c[1] = A * e + B * i + t * o + u * r;
    c[2] = A * g + B * j + t * m + u * s;
    c[3] = A * f + B * k + t * n + u * a;
    c[4] = v * d + w * h + x * l + y * p;
    c[5] = v * e + w * i + x * o + y * r;
    c[6] = v * g + w * j + x * m + y * s;
    c[7] = v * f + w * k + x * n + y * a;
    c[8] = z * d + C * h + D * l + E * p;
    c[9] = z * e + C * i + D * o + E * r;
    c[10] = z *
    g + C * j + D * m + E * s;
    c[11] = z * f + C * k + D * n + E * a;
    c[12] = q * d + F * h + G * l + b * p;
    c[13] = q * e + F * i + G * o + b * r;
    c[14] = q * g + F * j + G * m + b * s;
    c[15] = q * f + F * k + G * n + b * a;
    return c
};
mat4.multiplyVec3 = function(a, b, c) {
    c || (c = b);
    var d = b[0], e = b[1];
    b = b[2];
    c[0] = a[0] * d + a[4] * e + a[8] * b + a[12];
    c[1] = a[1] * d + a[5] * e + a[9] * b + a[13];
    c[2] = a[2] * d + a[6] * e + a[10] * b + a[14];
    return c
};
mat4.multiplyVec4 = function(a, b, c) {
    c || (c = b);
    var d = b[0], e = b[1], g = b[2];
    b = b[3];
    c[0] = a[0] * d + a[4] * e + a[8] * g + a[12] * b;
    c[1] = a[1] * d + a[5] * e + a[9] * g + a[13] * b;
    c[2] = a[2] * d + a[6] * e + a[10] * g + a[14] * b;
    c[3] = a[3] * d + a[7] * e + a[11] * g + a[15] * b;
    return c
};
mat4.translate = function(a, b, c) {
    var d = b[0], e = b[1];
    b = b[2];
    if (!c || a == c) {
        a[12] = a[0] * d + a[4] * e + a[8] * b + a[12];
        a[13] = a[1] * d + a[5] * e + a[9] * b + a[13];
        a[14] = a[2] * d + a[6] * e + a[10] * b + a[14];
        a[15] = a[3] * d + a[7] * e + a[11] * b + a[15];
        return a
    }
    var g = a[0], f = a[1], h = a[2], i = a[3], j = a[4], k = a[5], l = a[6], o = a[7], m = a[8], n = a[9], p = a[10], r = a[11];
    c[0] = g;
    c[1] = f;
    c[2] = h;
    c[3] = i;
    c[4] = j;
    c[5] = k;
    c[6] = l;
    c[7] = o;
    c[8] = m;
    c[9] = n;
    c[10] = p;
    c[11] = r;
    c[12] = g * d + j * e + m * b + a[12];
    c[13] = f * d + k * e + n * b + a[13];
    c[14] = h * d + l * e + p * b + a[14];
    c[15] = i * d + o * e + r * b + a[15];
    return c
};
mat4.scale = function(a, b, c) {
    var d = b[0], e = b[1];
    b = b[2];
    if (!c || a == c) {
        a[0]*=d;
        a[1]*=d;
        a[2]*=d;
        a[3]*=d;
        a[4]*=e;
        a[5]*=e;
        a[6]*=e;
        a[7]*=e;
        a[8]*=b;
        a[9]*=b;
        a[10]*=b;
        a[11]*=b;
        return a
    }
    c[0] = a[0] * d;
    c[1] = a[1] * d;
    c[2] = a[2] * d;
    c[3] = a[3] * d;
    c[4] = a[4] * e;
    c[5] = a[5] * e;
    c[6] = a[6] * e;
    c[7] = a[7] * e;
    c[8] = a[8] * b;
    c[9] = a[9] * b;
    c[10] = a[10] * b;
    c[11] = a[11] * b;
    c[12] = a[12];
    c[13] = a[13];
    c[14] = a[14];
    c[15] = a[15];
    return c
};
mat4.rotate = function(a, b, c, d) {
    var e = c[0], g = c[1];
    c = c[2];
    var f = Math.sqrt(e * e + g * g + c * c);
    if (!f)
        return null;
    if (f != 1) {
        f = 1 / f;
        e*=f;
        g*=f;
        c*=f
    }
    var h = Math.sin(b), i = Math.cos(b), j = 1 - i;
    b = a[0];
    f = a[1];
    var k = a[2], l = a[3], o = a[4], m = a[5], n = a[6], p = a[7], r = a[8], s = a[9], A = a[10], B = a[11], t = e * e * j + i, u = g * e * j + c * h, v = c * e * j - g * h, w = e * g * j - c * h, x = g * g * j + i, y = c * g * j + e * h, z = e * c * j + g * h;
    e = g * c * j - e * h;
    g = c * c * j + i;
    if (d) {
        if (a != d) {
            d[12] = a[12];
            d[13] = a[13];
            d[14] = a[14];
            d[15] = a[15]
        }
    } else 
        d = a;
    d[0] = b * t + o * u + r * v;
    d[1] = f * t + m * u + s * v;
    d[2] = k * t + n * u + A * v;
    d[3] = l * t + p * u + B *
    v;
    d[4] = b * w + o * x + r * y;
    d[5] = f * w + m * x + s * y;
    d[6] = k * w + n * x + A * y;
    d[7] = l * w + p * x + B * y;
    d[8] = b * z + o * e + r * g;
    d[9] = f * z + m * e + s * g;
    d[10] = k * z + n * e + A * g;
    d[11] = l * z + p * e + B * g;
    return d
};
mat4.rotateX = function(a, b, c) {
    var d = Math.sin(b);
    b = Math.cos(b);
    var e = a[4], g = a[5], f = a[6], h = a[7], i = a[8], j = a[9], k = a[10], l = a[11];
    if (c) {
        if (a != c) {
            c[0] = a[0];
            c[1] = a[1];
            c[2] = a[2];
            c[3] = a[3];
            c[12] = a[12];
            c[13] = a[13];
            c[14] = a[14];
            c[15] = a[15]
        }
    } else 
        c = a;
    c[4] = e * b + i * d;
    c[5] = g * b + j * d;
    c[6] = f * b + k * d;
    c[7] = h * b + l * d;
    c[8] = e*-d + i * b;
    c[9] = g*-d + j * b;
    c[10] = f*-d + k * b;
    c[11] = h*-d + l * b;
    return c
};
mat4.rotateY = function(a, b, c) {
    var d = Math.sin(b);
    b = Math.cos(b);
    var e = a[0], g = a[1], f = a[2], h = a[3], i = a[8], j = a[9], k = a[10], l = a[11];
    if (c) {
        if (a != c) {
            c[4] = a[4];
            c[5] = a[5];
            c[6] = a[6];
            c[7] = a[7];
            c[12] = a[12];
            c[13] = a[13];
            c[14] = a[14];
            c[15] = a[15]
        }
    } else 
        c = a;
    c[0] = e * b + i*-d;
    c[1] = g * b + j*-d;
    c[2] = f * b + k*-d;
    c[3] = h * b + l*-d;
    c[8] = e * d + i * b;
    c[9] = g * d + j * b;
    c[10] = f * d + k * b;
    c[11] = h * d + l * b;
    return c
};
mat4.rotateZ = function(a, b, c) {
    var d = Math.sin(b);
    b = Math.cos(b);
    var e = a[0], g = a[1], f = a[2], h = a[3], i = a[4], j = a[5], k = a[6], l = a[7];
    if (c) {
        if (a != c) {
            c[8] = a[8];
            c[9] = a[9];
            c[10] = a[10];
            c[11] = a[11];
            c[12] = a[12];
            c[13] = a[13];
            c[14] = a[14];
            c[15] = a[15]
        }
    } else 
        c = a;
    c[0] = e * b + i * d;
    c[1] = g * b + j * d;
    c[2] = f * b + k * d;
    c[3] = h * b + l * d;
    c[4] = e*-d + i * b;
    c[5] = g*-d + j * b;
    c[6] = f*-d + k * b;
    c[7] = h*-d + l * b;
    return c
};
mat4.frustum = function(a, b, c, d, e, g, f) {
    f || (f = mat4.create());
    var h = b - a, i = d - c, j = g - e;
    f[0] = e * 2 / h;
    f[1] = 0;
    f[2] = 0;
    f[3] = 0;
    f[4] = 0;
    f[5] = e * 2 / i;
    f[6] = 0;
    f[7] = 0;
    f[8] = (b + a) / h;
    f[9] = (d + c) / i;
    f[10] =- (g + e) / j;
    f[11] =- 1;
    f[12] = 0;
    f[13] = 0;
    f[14] =- (g * e * 2) / j;
    f[15] = 0;
    return f
};
mat4.perspective = function(a, b, c, d, e) {
    a = c * Math.tan(a * Math.PI / 360);
    b = a * b;
    return mat4.frustum( - b, b, - a, a, c, d, e)
};
mat4.ortho = function(a, b, c, d, e, g, f) {
    f || (f = mat4.create());
    var h = b - a, i = d - c, j = g - e;
    f[0] = 2 / h;
    f[1] = 0;
    f[2] = 0;
    f[3] = 0;
    f[4] = 0;
    f[5] = 2 / i;
    f[6] = 0;
    f[7] = 0;
    f[8] = 0;
    f[9] = 0;
    f[10] =- 2 / j;
    f[11] = 0;
    f[12] =- (a + b) / h;
    f[13] =- (d + c) / i;
    f[14] =- (g + e) / j;
    f[15] = 1;
    return f
};
mat4.lookAt = function(a, b, c, d) {
    d || (d = mat4.create());
    var e = a[0], g = a[1];
    a = a[2];
    var f = c[0], h = c[1], i = c[2];
    c = b[1];
    var j = b[2];
    if (e == b[0] && g == c && a == j)
        return mat4.identity(d);
    var k, l, o, m;
    c = e - b[0];
    j = g - b[1];
    b = a - b[2];
    m = 1 / Math.sqrt(c * c + j * j + b * b);
    c*=m;
    j*=m;
    b*=m;
    k = h * b - i * j;
    i = i * c - f * b;
    f = f * j - h * c;
    if (m = Math.sqrt(k * k + i * i + f * f)) {
        m = 1 / m;
        k*=m;
        i*=m;
        f*=m
    } else 
        f = i = k = 0;
    h = j * f - b * i;
    l = b * k - c * f;
    o = c * i - j * k;
    if (m = Math.sqrt(h * h + l * l + o * o)) {
        m = 1 / m;
        h*=m;
        l*=m;
        o*=m
    } else 
        o = l = h = 0;
    d[0] = k;
    d[1] = h;
    d[2] = c;
    d[3] = 0;
    d[4] = i;
    d[5] = l;
    d[6] = j;
    d[7] = 0;
    d[8] = f;
    d[9] =
    o;
    d[10] = b;
    d[11] = 0;
    d[12] =- (k * e + i * g + f * a);
    d[13] =- (h * e + l * g + o * a);
    d[14] =- (c * e + j * g + b * a);
    d[15] = 1;
    return d
};
mat4.str = function(a) {
    return "[" + a[0] + ", " + a[1] + ", " + a[2] + ", " + a[3] + ", " + a[4] + ", " + a[5] + ", " + a[6] + ", " + a[7] + ", " + a[8] + ", " + a[9] + ", " + a[10] + ", " + a[11] + ", " + a[12] + ", " + a[13] + ", " + a[14] + ", " + a[15] + "]"
};
quat4 = {};
quat4.create = function(a) {
    var b = new glMatrixArrayType(4);
    if (a) {
        b[0] = a[0];
        b[1] = a[1];
        b[2] = a[2];
        b[3] = a[3]
    }
    return b
};
quat4.set = function(a, b) {
    b[0] = a[0];
    b[1] = a[1];
    b[2] = a[2];
    b[3] = a[3];
    return b
};
quat4.calculateW = function(a, b) {
    var c = a[0], d = a[1], e = a[2];
    if (!b || a == b) {
        a[3] =- Math.sqrt(Math.abs(1 - c * c - d * d - e * e));
        return a
    }
    b[0] = c;
    b[1] = d;
    b[2] = e;
    b[3] =- Math.sqrt(Math.abs(1 - c * c - d * d - e * e));
    return b
};
quat4.inverse = function(a, b) {
    if (!b || a == b) {
        a[0]*=1;
        a[1]*=1;
        a[2]*=1;
        return a
    }
    b[0] =- a[0];
    b[1] =- a[1];
    b[2] =- a[2];
    b[3] = a[3];
    return b
};
quat4.length = function(a) {
    var b = a[0], c = a[1], d = a[2];
    a = a[3];
    return Math.sqrt(b * b + c * c + d * d + a * a)
};
quat4.normalize = function(a, b) {
    b || (b = a);
    var c = a[0], d = a[1], e = a[2], g = a[3], f = Math.sqrt(c * c + d * d + e * e + g * g);
    if (f == 0) {
        b[0] = 0;
        b[1] = 0;
        b[2] = 0;
        b[3] = 0;
        return b
    }
    f = 1 / f;
    b[0] = c * f;
    b[1] = d * f;
    b[2] = e * f;
    b[3] = g * f;
    return b
};
quat4.multiply = function(a, b, c) {
    c || (c = a);
    var d = a[0], e = a[1], g = a[2];
    a = a[3];
    var f = b[0], h = b[1], i = b[2];
    b = b[3];
    c[0] = d * b + a * f + e * i - g * h;
    c[1] = e * b + a * h + g * f - d * i;
    c[2] = g * b + a * i + d * h - e * f;
    c[3] = a * b - d * f - e * h - g * i;
    return c
};
quat4.multiplyVec3 = function(a, b, c) {
    c || (c = b);
    var d = b[0], e = b[1], g = b[2];
    b = a[0];
    var f = a[1], h = a[2];
    a = a[3];
    var i = a * d + f * g - h * e, j = a * e + h * d - b * g, k = a * g + b * e - f * d;
    d =- b * d - f * e - h * g;
    c[0] = i * a + d*-b + j*-h - k*-f;
    c[1] = j * a + d*-f + k*-b - i*-h;
    c[2] = k * a + d*-h + i*-f - j*-b;
    return c
};
quat4.toMat3 = function(a, b) {
    b || (b = mat3.create());
    var c = a[0], d = a[1], e = a[2], g = a[3], f = c + c, h = d + d, i = e + e, j = c * f, k = c * h;
    c = c * i;
    var l = d * h;
    d = d * i;
    e = e * i;
    f = g * f;
    h = g * h;
    g = g * i;
    b[0] = 1 - (l + e);
    b[1] = k - g;
    b[2] = c + h;
    b[3] = k + g;
    b[4] = 1 - (j + e);
    b[5] = d - f;
    b[6] = c - h;
    b[7] = d + f;
    b[8] = 1 - (j + l);
    return b
};
quat4.toMat4 = function(a, b) {
    b || (b = mat4.create());
    var c = a[0], d = a[1], e = a[2], g = a[3], f = c + c, h = d + d, i = e + e, j = c * f, k = c * h;
    c = c * i;
    var l = d * h;
    d = d * i;
    e = e * i;
    f = g * f;
    h = g * h;
    g = g * i;
    b[0] = 1 - (l + e);
    b[1] = k - g;
    b[2] = c + h;
    b[3] = 0;
    b[4] = k + g;
    b[5] = 1 - (j + e);
    b[6] = d - f;
    b[7] = 0;
    b[8] = c - h;
    b[9] = d + f;
    b[10] = 1 - (j + l);
    b[11] = 0;
    b[12] = 0;
    b[13] = 0;
    b[14] = 0;
    b[15] = 1;
    return b
};
quat4.slerp = function(a, b, c, d) {
    d || (d = a);
    var e = c;
    if (a[0] * b[0] + a[1] * b[1] + a[2] * b[2] + a[3] * b[3] < 0)
        e =- 1 * c;
    d[0] = 1 - c * a[0] + e * b[0];
    d[1] = 1 - c * a[1] + e * b[1];
    d[2] = 1 - c * a[2] + e * b[2];
    d[3] = 1 - c * a[3] + e * b[3];
    return d
};
quat4.str = function(a) {
    return "[" + a[0] + ", " + a[1] + ", " + a[2] + ", " + a[3] + "]"
};