#本文主要参考自《WebGL 编程指南》
所需要的库文件：
cuon-matrix.js
// cuon-matrix.js (c) 2012 kanda and matsuda
/**
* This is a class treating 4x4 matrix.
* This class contains the function that is equivalent to OpenGL matrix stack.
* The matrix after conversion is calculated by multiplying a conversion matrix from the right.
* The matrix is replaced by the calculated result.
*/
/**
* Constructor of Matrix4
* If opt_src is specified, new matrix is initialized by opt_src.
* Otherwise, new matrix is initialized by identity matrix.
* @param opt_src source matrix(option)
*/
var Matrix4 = function(opt_src) {
var i, s, d;
if (opt_src && typeof opt_src === ‘object‘ && opt_src.hasOwnProperty(‘elements‘)) {
s = opt_src.elements;
d = new Float32Array(16);
for (i = 0; i < 16; ++i) {
d[i] = s[i];
}
this.elements = d;
} else {
this.elements = new Float32Array([1,0,0,0, 0,1,0,0, 0,0,1,0, 0,0,0,1]);
}
};
/**
* Set the identity matrix.
* @return this
*/
Matrix4.prototype.setIdentity = function() {
var e = this.elements;
e[0] = 1; e[4] = 0; e[8] = 0; e[12] = 0;
e[1] = 0; e[5] = 1; e[9] = 0; e[13] = 0;
e[2] = 0; e[6] = 0; e[10] = 1; e[14] = 0;
e[3] = 0; e[7] = 0; e[11] = 0; e[15] = 1;
return this;
};
/**
* Copy matrix.
* @param src source matrix
* @return this
*/
Matrix4.prototype.set = function(src) {
var i, s, d;
s = src.elements;
d = this.elements;
if (s === d) {
return;
}
for (i = 0; i < 16; ++i) {
d[i] = s[i];
}
return this;
};
/**
* Multiply the matrix from the right.
* @param other The multiply matrix
* @return this
*/
Matrix4.prototype.concat = function(other) {
var i, e, a, b, ai0, ai1, ai2, ai3;
// Calculate e = a * b
e = this.elements;
a = this.elements;
b = other.elements;
// If e equals b, copy b to temporary matrix.
if (e === b) {
b = new Float32Array(16);
for (i = 0; i < 16; ++i) {
b[i] = e[i];
}
}
for (i = 0; i < 4; i++) {
ai0=a[i]; ai1=a[i+4]; ai2=a[i+8]; ai3=a[i+12];
e[i] = ai0 * b[0] + ai1 * b[1] + ai2 * b[2] + ai3 * b[3];
e[i+4] = ai0 * b[4] + ai1 * b[5] + ai2 * b[6] + ai3 * b[7];
e[i+8] = ai0 * b[8] + ai1 * b[9] + ai2 * b[10] + ai3 * b[11];
e[i+12] = ai0 * b[12] + ai1 * b[13] + ai2 * b[14] + ai3 * b[15];
}
return this;
};
Matrix4.prototype.multiply = Matrix4.prototype.concat;
/**
* Multiply the three-dimensional vector.
* @param pos The multiply vector
* @return The result of multiplication(Float32Array)
*/
Matrix4.prototype.multiplyVector3 = function(pos) {
var e = this.elements;
var p = pos.elements;
var v = new Vector3();
var result = v.elements;
result[0] = p[0] * e[0] + p[1] * e[4] + p[2] * e[ 8] + e[11];
result[1] = p[0] * e[1] + p[1] * e[5] + p[2] * e[ 9] + e[12];
result[2] = p[0] * e[2] + p[1] * e[6] + p[2] * e[10] + e[13];
return v;
};
/**
* Multiply the four-dimensional vector.
* @param pos The multiply vector
* @return The result of multiplication(Float32Array)
*/
Matrix4.prototype.multiplyVector4 = function(pos) {
var e = this.elements;
var p = pos.elements;
var v = new Vector4();
var result = v.elements;
result[0] = p[0] * e[0] + p[1] * e[4] + p[2] * e[ 8] + p[3] * e[12];
result[1] = p[0] * e[1] + p[1] * e[5] + p[2] * e[ 9] + p[3] * e[13];
result[2] = p[0] * e[2] + p[1] * e[6] + p[2] * e[10] + p[3] * e[14];
result[3] = p[0] * e[3] + p[1] * e[7] + p[2] * e[11] + p[3] * e[15];
return v;
};
/**
* Transpose the matrix.
* @return this
*/
Matrix4.prototype.transpose = function() {
var e, t;
e = this.elements;
t = e[ 1]; e[ 1] = e[ 4]; e[ 4] = t;
t = e[ 2]; e[ 2] = e[ 8]; e[ 8] = t;
t = e[ 3]; e[ 3] = e[12]; e[12] = t;
t = e[ 6]; e[ 6] = e[ 9]; e[ 9] = t;
t = e[ 7]; e[ 7] = e[13]; e[13] = t;
t = e[11]; e[11] = e[14]; e[14] = t;
return this;
};
/**
* Calculate the inverse matrix of specified matrix, and set to this.
* @param other The source matrix
* @return this
*/
Matrix4.prototype.setInverseOf = function(other) {
var i, s, d, inv, det;
s = other.elements;
d = this.elements;
inv = new Float32Array(16);
inv[0] = s[5]*s[10]*s[15] - s[5] *s[11]*s[14] - s[9] *s[6]*s[15]
+ s[9]*s[7] *s[14] + s[13]*s[6] *s[11] - s[13]*s[7]*s[10];
inv[4] = - s[4]*s[10]*s[15] + s[4] *s[11]*s[14] + s[8] *s[6]*s[15]
- s[8]*s[7] *s[14] - s[12]*s[6] *s[11] + s[12]*s[7]*s[10];
inv[8] = s[4]*s[9] *s[15] - s[4] *s[11]*s[13] - s[8] *s[5]*s[15]
+ s[8]*s[7] *s[13] + s[12]*s[5] *s[11] - s[12]*s[7]*s[9];
inv[12] = - s[4]*s[9] *s[14] + s[4] *s[10]*s[13] + s[8] *s[5]*s[14]
- s[8]*s[6] *s[13] - s[12]*s[5] *s[10] + s[12]*s[6]*s[9];
inv[1] = - s[1]*s[10]*s[15] + s[1] *s[11]*s[14] + s[9] *s[2]*s[15]
- s[9]*s[3] *s[14] - s[13]*s[2] *s[11] + s[13]*s[3]*s[10];
inv[5] = s[0]*s[10]*s[15] - s[0] *s[11]*s[14] - s[8] *s[2]*s[15]
+ s[8]*s[3] *s[14] + s[12]*s[2] *s[11] - s[12]*s[3]*s[10];
inv[9] = - s[0]*s[9] *s[15] + s[0] *s[11]*s[13] + s[8] *s[1]*s[15]
- s[8]*s[3] *s[13] - s[12]*s[1] *s[11] + s[12]*s[3]*s[9];
inv[13] = s[0]*s[9] *s[14] - s[0] *s[10]*s[13] - s[8] *s[1]*s[14]
+ s[8]*s[2] *s[13] + s[12]*s[1] *s[10] - s[12]*s[2]*s[9];
inv[2] = s[1]*s[6]*s[15] - s[1] *s[7]*s[14] - s[5] *s[2]*s[15]
+ s[5]*s[3]*s[14] + s[13]*s[2]*s[7] - s[13]*s[3]*s[6];
inv[6] = - s[0]*s[6]*s[15] + s[0] *s[7]*s[14] + s[4] *s[2]*s[15]
- s[4]*s[3]*s[14] - s[12]*s[2]*s[7] + s[12]*s[3]*s[6];
inv[10] = s[0]*s[5]*s[15] - s[0] *s[7]*s[13] - s[4] *s[1]*s[15]
+ s[4]*s[3]*s[13] + s[12]*s[1]*s[7] - s[12]*s[3]*s[5];
inv[14] = - s[0]*s[5]*s[14] + s[0] *s[6]*s[13] + s[4] *s[1]*s[14]
- s[4]*s[2]*s[13] - s[12]*s[1]*s[6] + s[12]*s[2]*s[5];
inv[3] = - s[1]*s[6]*s[11] + s[1]*s[7]*s[10] + s[5]*s[2]*s[11]
- s[5]*s[3]*s[10] - s[9]*s[2]*s[7] + s[9]*s[3]*s[6];
inv[7] = s[0]*s[6]*s[11] - s[0]*s[7]*s[10] - s[4]*s[2]*s[11]
+ s[4]*s[3]*s[10] + s[8]*s[2]*s[7] - s[8]*s[3]*s[6];
inv[11] = - s[0]*s[5]*s[11] + s[0]*s[7]*s[9] + s[4]*s[1]*s[11]
- s[4]*s[3]*s[9] - s[8]*s[1]*s[7] + s[8]*s[3]*s[5];
inv[15] = s[0]*s[5]*s[10] - s[0]*s[6]*s[9] - s[4]*s[1]*s[10]
+ s[4]*s[2]*s[9] + s[8]*s[1]*s[6] - s[8]*s[2]*s[5];
det = s[0]*inv[0] + s[1]*inv[4] + s[2]*inv[8] + s[3]*inv[12];
if (det === 0) {
return this;
}
det = 1 / det;
for (i = 0; i < 16; i++) {
d[i] = inv[i] * det;
}
return this;
};
/**
* Calculate the inverse matrix of this, and set to this.
* @return this
*/
Matrix4.prototype.invert = function() {
return this.setInverseOf(this);
};
/**
* Set the orthographic projection matrix.
* @param left The coordinate of the left of clipping plane.
* @param right The coordinate of the right of clipping plane.
* @param bottom The coordinate of the bottom of clipping plane.
* @param top The coordinate of the top top clipping plane.
* @param near The distances to the nearer depth clipping plane. This value is minus if the plane is to be behind the viewer.
* @param far The distances to the farther depth clipping plane. This value is minus if the plane is to be behind the viewer.
* @return this
*/
Matrix4.prototype.setOrtho = function(left, right, bottom, top, near, far) {
var e, rw, rh, rd;
if (left === right || bottom === top || near === far) {
throw ‘null frustum‘;
}
rw = 1 / (right - left);
rh = 1 / (top - bottom);
rd = 1 / (far - near);
e = this.elements;
e[0] = 2 * rw;
e[1] = 0;
e[2] = 0;
e[3] = 0;
e[4] = 0;
e[5] = 2 * rh;
e[6] = 0;
e[7] = 0;
e[8] = 0;
e[9] = 0;
e[10] = -2 * rd;
e[11] = 0;
e[12] = -(right + left) * rw;
e[13] = -(top + bottom) * rh;
e[14] = -(far + near) * rd;
e[15] = 1;
return this;
};
/**
* Multiply the orthographic projection matrix from the right.
* @param left The coordinate of the left of clipping plane.
* @param right The coordinate of the right of clipping plane.
* @param bottom The coordinate of the bottom of clipping plane.
* @param top The coordinate of the top top clipping plane.
* @param near The distances to the nearer depth clipping plane. This value is minus if the plane is to be behind the viewer.
* @param far The distances to the farther depth clipping plane. This value is minus if the plane is to be behind the viewer.
* @return this
*/
Matrix4.prototype.ortho = function(left, right, bottom, top, near, far) {
return this.concat(new Matrix4().setOrtho(left, right, bottom, top, near, far));
};
/**
* Set the perspective projection matrix.
* @param left The coordinate of the left of clipping plane.
* @param right The coordinate of the right of clipping plane.
* @param bottom The coordinate of the bottom of clipping plane.
* @param top The coordinate of the top top clipping plane.
* @param near The distances to the nearer depth clipping plane. This value must be plus value.
* @param far The distances to the farther depth clipping plane. This value must be plus value.
* @return this
*/
Matrix4.prototype.setFrustum = function(left, right, bottom, top, near, far) {
var e, rw, rh, rd;
if (left === right || top === bottom || near === far) {
throw ‘null frustum‘;
}
if (near <= 0) {
throw ‘near <= 0‘;
}
if (far <= 0) {
throw ‘far <= 0‘;
}
rw = 1 / (right - left);
rh = 1 / (top - bottom);
rd = 1 / (far - near);
e = this.elements;
e[ 0] = 2 * near * rw;
e[ 1] = 0;
e[ 2] = 0;
e[ 3] = 0;
e[ 4] = 0;
e[ 5] = 2 * near * rh;
e[ 6] = 0;
e[ 7] = 0;
e[ 8] = (right + left) * rw;
e[ 9] = (top + bottom) * rh;
e[10] = -(far + near) * rd;
e[11] = -1;
e[12] = 0;
e[13] = 0;
e[14] = -2 * near * far * rd;
e[15] = 0;
return this;
};
/**
* Multiply the perspective projection matrix from the right.
* @param left The coordinate of the left of clipping plane.
* @param right The coordinate of the right of clipping plane.
* @param bottom The coordinate of the bottom of clipping plane.
* @param top The coordinate of the top top clipping plane.
* @param near The distances to the nearer depth clipping plane. This value must be plus value.
* @param far The distances to the farther depth clipping plane. This value must be plus value.
* @return this
*/
Matrix4.prototype.frustum = function(left, right, bottom, top, near, far) {
return this.concat(new Matrix4().setFrustum(left, right, bottom, top, near, far));
};
/**
* Set the perspective projection matrix by fovy and aspect.
* @param fovy The angle between the upper and lower sides of the frustum.
* @param aspect The aspect ratio of the frustum. (width/height)
* @param near The distances to the nearer depth clipping plane. This value must be plus value.
* @param far The distances to the farther depth clipping plane. This value must be plus value.
* @return this
*/
Matrix4.prototype.setPerspective = function(fovy, aspect, near, far) {
var e, rd, s, ct;
if (near === far || aspect === 0) {
throw ‘null frustum‘;
}
if (near <= 0) {
throw ‘near <= 0‘;
}
if (far <= 0) {
throw ‘far <= 0‘;
}
fovy = Math.PI * fovy / 180 / 2;
s = Math.sin(fovy);
if (s === 0) {
throw ‘null frustum‘;
}
rd = 1 / (far - near);
ct = Math.cos(fovy) / s;
e = this.elements;
e[0] = ct / aspect;
e[1] = 0;
e[2] = 0;
e[3] = 0;
e[4] = 0;
e[5] = ct;
e[6] = 0;
e[7] = 0;
e[8] = 0;
e[9] = 0;
e[10] = -(far + near) * rd;
e[11] = -1;
e[12] = 0;
e[13] = 0;
e[14] = -2 * near * far * rd;
e[15] = 0;
return this;
};
/**
* Multiply the perspective projection matrix from the right.
* @param fovy The angle between the upper and lower sides of the frustum.
* @param aspect The aspect ratio of the frustum. (width/height)
* @param near The distances to the nearer depth clipping plane. This value must be plus value.
* @param far The distances to the farther depth clipping plane. This value must be plus value.
* @return this
*/
Matrix4.prototype.perspective = function(fovy, aspect, near, far) {
return this.concat(new Matrix4().setPerspective(fovy, aspect, near, far));
};
/**
* Set the matrix for scaling.
* @param x The scale factor along the X axis
* @param y The scale factor along the Y axis
* @param z The scale factor along the Z axis
* @return this
*/
Matrix4.prototype.setScale = function(x, y, z) {
var e = this.elements;
e[0] = x; e[4] = 0; e[8] = 0; e[12] = 0;
e[1] = 0; e[5] = y; e[9] = 0; e[13] = 0;
e[2] = 0; e[6] = 0; e[10] = z; e[14] = 0;
e[3] = 0; e[7] = 0; e[11] = 0; e[15] = 1;
return this;
};
/**
* Multiply the matrix for scaling from the right.
* @param x The scale factor along the X axis
* @param y The scale factor along the Y axis
* @param z The scale factor along the Z axis
* @return this
*/
Matrix4.prototype.scale = function(x, y, z) {
var e = this.elements;
e[0] *= x; e[4] *= y; e[8] *= z;
e[1] *= x; e[5] *= y; e[9] *= z;
e[2] *= x; e[6] *= y; e[10] *= z;
e[3] *= x; e[7] *= y; e[11] *= z;
return this;
};
/**
* Set the matrix for translation.
* @param x The X value of a translation.
* @param y The Y value of a translation.
* @param z The Z value of a translation.
* @return this
*/
Matrix4.prototype.setTranslate = function(x, y, z) {
var e = this.elements;
e[0] = 1; e[4] = 0; e[8] = 0; e[12] = x;
e[1] = 0; e[5] = 1; e[9] = 0; e[13] = y;
e[2] = 0; e[6] = 0; e[10] = 1; e[14] = z;
e[3] = 0; e[7] = 0; e[11] = 0; e[15] = 1;
return this;
};
/**
* Multiply the matrix for translation from the right.
* @param x The X value of a translation.
* @param y The Y value of a translation.
* @param z The Z value of a translation.
* @return this
*/
Matrix4.prototype.translate = function(x, y, z) {
var e = this.elements;
e[12] += e[0] * x + e[4] * y + e[8] * z;
e[13] += e[1] * x + e[5] * y + e[9] * z;
e[14] += e[2] * x + e[6] * y + e[10] * z;
e[15] += e[3] * x + e[7] * y + e[11] * z;
return this;
};
/**
* Set the matrix for rotation.
* The vector of rotation axis may not be normalized.
* @param angle The angle of rotation (degrees)
* @param x The X coordinate of vector of rotation axis.
* @param y The Y coordinate of vector of rotation axis.
* @param z The Z coordinate of vector of rotation axis.
* @return this
*/
Matrix4.prototype.setRotate = function(angle, x, y, z) {
var e, s, c, len, rlen, nc, xy, yz, zx, xs, ys, zs;
angle = Math.PI * angle / 180;
e = this.elements;
s = Math.sin(angle);
c = Math.cos(angle);
if (0 !== x && 0 === y && 0 === z) {
// Rotation around X axis
if (x < 0) {
s = -s;
}
e[0] = 1; e[4] = 0; e[ 8] = 0; e[12] = 0;
e[1] = 0; e[5] = c; e[ 9] =-s; e[13] = 0;
e[2] = 0; e[6] = s; e[10] = c; e[14] = 0;
e[3] = 0; e[7] = 0; e[11] = 0; e[15] = 1;
} else if (0 === x && 0 !== y && 0 === z) {
// Rotation around Y axis
if (y < 0) {
s = -s;
}
e[0] = c; e[4] = 0; e[ 8] = s; e[12] = 0;
e[1] = 0; e[5] = 1; e[ 9] = 0; e[13] = 0;
e[2] =-s; e[6] = 0; e[10] = c; e[14] = 0;
e[3] = 0; e[7] = 0; e[11] = 0; e[15] = 1;
} else if (0 === x && 0 === y && 0 !== z) {
// Rotation around Z axis
if (z < 0) {
s = -s;
}
e[0] = c; e[4] =-s; e[ 8] = 0; e[12] = 0;
e[1] = s; e[5] = c; e[ 9] = 0; e[13] = 0;
e[2] = 0; e[6] = 0; e[10] = 1; e[14] = 0;
e[3] = 0; e[7] = 0; e[11] = 0; e[15] = 1;
} else {
// Rotation around another axis
len = Math.sqrt(x*x + y*y + z*z);
if (len !== 1) {
rlen = 1 / len;
x *= rlen;
y *= rlen;
z *= rlen;
}
nc = 1 - c;
xy = x * y;
yz = y * z;
zx = z * x;
xs = x * s;
ys = y * s;
zs = z * s;
e[ 0] = x*x*nc + c;
e[ 1] = xy *nc + zs;
e[ 2] = zx *nc - ys;
e[ 3] = 0;
e[ 4] = xy *nc - zs;
e[ 5] = y*y*nc + c;
e[ 6] = yz *nc + xs;
e[ 7] = 0;
e[ 8] = zx *nc + ys;
e[ 9] = yz *nc - xs;
e[10] = z*z*nc + c;
e[11] = 0;
e[12] = 0;
e[13] = 0;
e[14] = 0;
e[15] = 1;
}
return this;
};
/**
* Multiply the matrix for rotation from the right.
* The vector of rotation axis may not be normalized.
* @param angle The angle of rotation (degrees)
* @param x The X coordinate of vector of rotation axis.
* @param y The Y coordinate of vector of rotation axis.
* @param z The Z coordinate of vector of rotation axis.
* @return this
*/
Matrix4.prototype.rotate = function(angle, x, y, z) {
return this.concat(new Matrix4().setRotate(angle, x, y, z));
};
/**
* Set the viewing matrix.
* @param eyeX, eyeY, eyeZ The position of the eye point.
* @param centerX, centerY, centerZ The position of the reference point.
* @param upX, upY, upZ The direction of the up vector.
* @return this
*/
Matrix4.prototype.setLookAt = function(eyeX, eyeY, eyeZ, centerX, centerY, centerZ, upX, upY, upZ) {
var e, fx, fy, fz, rlf, sx, sy, sz, rls, ux, uy, uz;
fx = centerX - eyeX;
fy = centerY - eyeY;
fz = centerZ - eyeZ;
// Normalize f.
rlf = 1 / Math.sqrt(fx*fx + fy*fy + fz*fz);
fx *= rlf;
fy *= rlf;
fz *= rlf;
// Calculate cross product of f and up.
sx = fy * upZ - fz * upY;
sy = fz * upX - fx * upZ;
sz = fx * upY - fy * upX;
// Normalize s.
rls = 1 / Math.sqrt(sx*sx + sy*sy + sz*sz);
sx *= rls;
sy *= rls;
sz *= rls;
// Calculate cross product of s and f.
ux = sy * fz - sz * fy;
uy = sz * fx - sx * fz;
uz = sx * fy - sy * fx;
// Set to this.
e = this.elements;
e[0] = sx;
e[1] = ux;
e[2] = -fx;
e[3] = 0;
e[4] = sy;
e[5] = uy;
e[6] = -fy;
e[7] = 0;
e[8] = sz;
e[9] = uz;
e[10] = -fz;
e[11] = 0;
e[12] = 0;
e[13] = 0;
e[14] = 0;
e[15] = 1;
// Translate.
return this.translate(-eyeX, -eyeY, -eyeZ);
};
/**
* Multiply the viewing matrix from the right.
* @param eyeX, eyeY, eyeZ The position of the eye point.
* @param centerX, centerY, centerZ The position of the reference point.
* @param upX, upY, upZ The direction of the up vector.
* @return this
*/
Matrix4.prototype.lookAt = function(eyeX, eyeY, eyeZ, centerX, centerY, centerZ, upX, upY, upZ) {
return this.concat(new Matrix4().setLookAt(eyeX, eyeY, eyeZ, centerX, centerY, centerZ, upX, upY, upZ));
};
/**
* Multiply the matrix for project vertex to plane from the right.
* @param plane The array[A, B, C, D] of the equation of plane "Ax + By + Cz + D = 0".
* @param light The array which stored coordinates of the light. if light[3]=0, treated as parallel light.
* @return this
*/
Matrix4.prototype.dropShadow = function(plane, light) {
var mat = new Matrix4();
var e = mat.elements;
var dot = plane[0] * light[0] + plane[1] * light[1] + plane[2] * light[2] + plane[3] * light[3];
e[ 0] = dot - light[0] * plane[0];
e[ 1] = - light[1] * plane[0];
e[ 2] = - light[2] * plane[0];
e[ 3] = - light[3] * plane[0];
e[ 4] = - light[0] * plane[1];
e[ 5] = dot - light[1] * plane[1];
e[ 6] = - light[2] * plane[1];
e[ 7] = - light[3] * plane[1];
e[ 8] = - light[0] * plane[2];
e[ 9] = - light[1] * plane[2];
e[10] = dot - light[2] * plane[2];
e[11] = - light[3] * plane[2];
e[12] = - light[0] * plane[3];
e[13] = - light[1] * plane[3];
e[14] = - light[2] * plane[3];
e[15] = dot - light[3] * plane[3];
return this.concat(mat);
}
/**
* Multiply the matrix for project vertex to plane from the right.(Projected by parallel light.)
* @param normX, normY, normZ The normal vector of the plane.(Not necessary to be normalized.)
* @param planeX, planeY, planeZ The coordinate of arbitrary points on a plane.
* @param lightX, lightY, lightZ The vector of the direction of light.(Not necessary to be normalized.)
* @return this
*/
Matrix4.prototype.dropShadowDirectionally = function(normX, normY, normZ, planeX, planeY, planeZ, lightX, lightY, lightZ) {
var a = planeX * normX + planeY * normY + planeZ * normZ;
return this.dropShadow([normX, normY, normZ, -a], [lightX, lightY, lightZ, 0]);
};
/**
* Constructor of Vector3
* If opt_src is specified, new vector is initialized by opt_src.
* @param opt_src source vector(option)
*/
var Vector3 = function(opt_src) {
var v = new Float32Array(3);
if (opt_src && typeof opt_src === ‘object‘) {
v[0] = opt_src[0]; v[1] = opt_src[1]; v[2] = opt_src[2];
}
this.elements = v;
}
/**
* Normalize.
* @return this
*/
Vector3.prototype.normalize = function() {
var v = this.elements;
var c = v[0], d = v[1], e = v[2], g = Math.sqrt(c*c+d*d+e*e);
if(g){
if(g == 1)
return this;
} else {
v[0] = 0; v[1] = 0; v[2] = 0;
return this;
}
g = 1/g;
v[0] = c*g; v[1] = d*g; v[2] = e*g;
return this;
};
/**
* Constructor of Vector4
* If opt_src is specified, new vector is initialized by opt_src.
* @param opt_src source vector(option)
*/
var Vector4 = function(opt_src) {
var v = new Float32Array(4);
if (opt_src && typeof opt_src === ‘object‘) {
v[0] = opt_src[0]; v[1] = opt_src[1]; v[2] = opt_src[2]; v[3] = opt_src[3];
}
this.elements = v;
}
cuon-utils.js
// cuon-utils.js (c) 2012 kanda and matsuda
/**
* Create a program object and make current
* @param gl GL context
* @param vshader a vertex shader program (string)
* @param fshader a fragment shader program (string)
* @return true, if the program object was created and successfully made current
*/
function initShaders(gl, vshader, fshader) {
var program = createProgram(gl, vshader, fshader);
if (!program) {
console.log(‘Failed to create program‘);
return false;
}
gl.useProgram(program);
gl.program = program;
return true;
}
/**
* Create the linked program object
* @param gl GL context
* @param vshader a vertex shader program (string)
* @param fshader a fragment shader program (string)
* @return created program object, or null if the creation has failed
*/
function createProgram(gl, vshader, fshader) {
// Create shader object
var vertexShader = loadShader(gl, gl.VERTEX_SHADER, vshader);
var fragmentShader = loadShader(gl, gl.FRAGMENT_SHADER, fshader);
if (!vertexShader || !fragmentShader) {
return null;
}
// Create a program object
var program = gl.createProgram();
if (!program) {
return null;
}
// Attach the shader objects
gl.attachShader(program, vertexShader);
gl.attachShader(program, fragmentShader);
// Link the program object
gl.linkProgram(program);
// Check the result of linking
var linked = gl.getProgramParameter(program, gl.LINK_STATUS);
if (!linked) {
var error = gl.getProgramInfoLog(program);
console.log(‘Failed to link program: ‘ + error);
gl.deleteProgram(program);
gl.deleteShader(fragmentShader);
gl.deleteShader(vertexShader);
return null;
}
return program;
}
/**
* Create a shader object
* @param gl GL context
* @param type the type of the shader object to be created
* @param source shader program (string)
* @return created shader object, or null if the creation has failed.
*/
function loadShader(gl, type, source) {
// Create shader object
var shader = gl.createShader(type);
if (shader == null) {
console.log(‘unable to create shader‘);
return null;
}
// Set the shader program
gl.shaderSource(shader, source);
// Compile the shader
gl.compileShader(shader);
// Check the result of compilation
var compiled = gl.getShaderParameter(shader, gl.COMPILE_STATUS);
if (!compiled) {
var error = gl.getShaderInfoLog(shader);
console.log(‘Failed to compile shader: ‘ + error);
gl.deleteShader(shader);
return null;
}
return shader;
}
/**
* Initialize and get the rendering for WebGL
* @param canvas <cavnas> element
* @param opt_debug flag to initialize the context for debugging
* @return the rendering context for WebGL
*/
function getWebGLContext(canvas, opt_debug) {
// Get the rendering context for WebGL
var gl = WebGLUtils.setupWebGL(canvas);
if (!gl) return null;
// if opt_debug is explicitly false, create the context for debugging
if (arguments.length < 2 || opt_debug) {
gl = WebGLDebugUtils.makeDebugContext(gl);
}
return gl;
}
webgl-debug.js
//Copyright (c) 2009 The Chromium Authors. All rights reserved.
//Use of this source code is governed by a BSD-style license that can be
//found in the LICENSE file.
// Various functions for helping debug WebGL apps.
WebGLDebugUtils = function() {
/**
* Wrapped logging function.
* @param {string} msg Message to log.
*/
var log = function(msg) {
if (window.console && window.console.log) {
window.console.log(msg);
}
};
/**
* Which arguements are enums.
* @type {!Object.<number, string>}
*/
var glValidEnumContexts = {
// Generic setters and getters
‘enable‘: { 0:true },
‘disable‘: { 0:true },
‘getParameter‘: { 0:true },
// Rendering
‘drawArrays‘: { 0:true },
‘drawElements‘: { 0:true, 2:true },
// Shaders
‘createShader‘: { 0:true },
‘getShaderParameter‘: { 1:true },
‘getProgramParameter‘: { 1:true },
// Vertex attributes
‘getVertexAttrib‘: { 1:true },
‘vertexAttribPointer‘: { 2:true },
// Textures
‘bindTexture‘: { 0:true },
‘activeTexture‘: { 0:true },
‘getTexParameter‘: { 0:true, 1:true },
‘texParameterf‘: { 0:true, 1:true },
‘texParameteri‘: { 0:true, 1:true, 2:true },
‘texImage2D‘: { 0:true, 2:true, 6:true, 7:true },
‘texSubImage2D‘: { 0:true, 6:true, 7:true },
‘copyTexImage2D‘: { 0:true, 2:true },
‘copyTexSubImage2D‘: { 0:true },
‘generateMipmap‘: { 0:true },
// Buffer objects
‘bindBuffer‘: { 0:true },
‘bufferData‘: { 0:true, 2:true },
‘bufferSubData‘: { 0:true },
‘getBufferParameter‘: { 0:true, 1:true },
// Renderbuffers and framebuffers
‘pixelStorei‘: { 0:true, 1:true },
‘readPixels‘: { 4:true, 5:true },
‘bindRenderbuffer‘: { 0:true },
‘bindFramebuffer‘: { 0:true },
‘checkFramebufferStatus‘: { 0:true },
‘framebufferRenderbuffer‘: { 0:true, 1:true, 2:true },
‘framebufferTexture2D‘: { 0:true, 1:true, 2:true },
‘getFramebufferAttachmentParameter‘: { 0:true, 1:true, 2:true },
‘getRenderbufferParameter‘: { 0:true, 1:true },
‘renderbufferStorage‘: { 0:true, 1:true },
// Frame buffer operations (clear, blend, depth test, stencil)
‘clear‘: { 0:true },
‘depthFunc‘: { 0:true },
‘blendFunc‘: { 0:true, 1:true },
‘blendFuncSeparate‘: { 0:true, 1:true, 2:true, 3:true },
‘blendEquation‘: { 0:true },
‘blendEquationSeparate‘: { 0:true, 1:true },
‘stencilFunc‘: { 0:true },
‘stencilFuncSeparate‘: { 0:true, 1:true },
‘stencilMaskSeparate‘: { 0:true },
‘stencilOp‘: { 0:true, 1:true, 2:true },
‘stencilOpSeparate‘: { 0:true, 1:true, 2:true, 3:true },
// Culling
‘cullFace‘: { 0:true },
‘frontFace‘: { 0:true },
};
/**
* Map of numbers to names.
* @type {Object}
*/
var glEnums = null;
/**
* Initializes this module. Safe to call more than once.
* @param {!WebGLRenderingContext} ctx A WebGL context. If
* you have more than one context it doesn‘t matter which one
* you pass in, it is only used to pull out constants.
*/
function init(ctx) {
if (glEnums == null) {
glEnums = { };
for (var propertyName in ctx) {
if (typeof ctx[propertyName] == ‘number‘) {
glEnums[ctx[propertyName]] = propertyName;
}
}
}
}
/**
* Checks the utils have been initialized.
*/
function checkInit() {
if (glEnums == null) {
throw ‘WebGLDebugUtils.init(ctx) not called‘;
}
}
/**
* Returns true or false if value matches any WebGL enum
* @param {*} value Value to check if it might be an enum.
* @return {boolean} True if value matches one of the WebGL defined enums
*/
function mightBeEnum(value) {
checkInit();
return (glEnums[value] !== undefined);
}
/**
* Gets an string version of an WebGL enum.
*
* Example:
* var str = WebGLDebugUtil.glEnumToString(ctx.getError());
*
* @param {number} value Value to return an enum for
* @return {string} The string version of the enum.
*/
function glEnumToString(value) {
checkInit();
var name = glEnums[value];
return (name !== undefined) ? name :
("*UNKNOWN WebGL ENUM (0x" + value.toString(16) + ")");
}
/**
* Returns the string version of a WebGL argument.
* Attempts to convert enum arguments to strings.
* @param {string} functionName the name of the WebGL function.
* @param {number} argumentIndx the index of the argument.
* @param {*} value The value of the argument.
* @return {string} The value as a string.
*/
function glFunctionArgToString(functionName, argumentIndex, value) {
var funcInfo = glValidEnumContexts[functionName];
if (funcInfo !== undefined) {
if (funcInfo[argumentIndex]) {
return glEnumToString(value);
}
}
return value.toString();
}
/**
* Given a WebGL context returns a wrapped context that calls
* gl.getError after every command and calls a function if the
* result is not gl.NO_ERROR.
*
* @param {!WebGLRenderingContext} ctx The webgl context to
* wrap.
* @param {!function(err, funcName, args): void} opt_onErrorFunc
* The function to call when gl.getError returns an
* error. If not specified the default function calls
* console.log with a message.
*/
function makeDebugContext(ctx, opt_onErrorFunc) {
init(ctx);
opt_onErrorFunc = opt_onErrorFunc || function(err, functionName, args) {
// apparently we can‘t do args.join(",");
var argStr = "";
for (var ii = 0; ii < args.length; ++ii) {
argStr += ((ii == 0) ? ‘‘ : ‘, ‘) +
glFunctionArgToString(functionName, ii, args[ii]);
}
log("WebGL error "+ glEnumToString(err) + " in "+ functionName +
"(" + argStr + ")");
};
// Holds booleans for each GL error so after we get the error ourselves
// we can still return it to the client app.
var glErrorShadow = { };
// Makes a function that calls a WebGL function and then calls getError.
function makeErrorWrapper(ctx, functionName) {
return function() {
var result = ctx[functionName].apply(ctx, arguments);
var err = ctx.getError();
if (err != 0) {
glErrorShadow[err] = true;
opt_onErrorFunc(err, functionName, arguments);
}
return result;
};
}
// Make a an object that has a copy of every property of the WebGL context
// but wraps all functions.
var wrapper = {};
for (var propertyName in ctx) {
if (typeof ctx[propertyName] == ‘function‘) {
wrapper[propertyName] = makeErrorWrapper(ctx, propertyName);
} else {
wrapper[propertyName] = ctx[propertyName];
}
}
// Override the getError function with one that returns our saved results.
wrapper.getError = function() {
for (var err in glErrorShadow) {
if (glErrorShadow[err]) {
glErrorShadow[err] = false;
return err;
}
}
return ctx.NO_ERROR;
};
return wrapper;
}
function resetToInitialState(ctx) {
var numAttribs = ctx.getParameter(ctx.MAX_VERTEX_ATTRIBS);
var tmp = ctx.createBuffer();
ctx.bindBuffer(ctx.ARRAY_BUFFER, tmp);
for (var ii = 0; ii < numAttribs; ++ii) {
ctx.disableVertexAttribArray(ii);
ctx.vertexAttribPointer(ii, 4, ctx.FLOAT, false, 0, 0);
ctx.vertexAttrib1f(ii, 0);
}
ctx.deleteBuffer(tmp);
var numTextureUnits = ctx.getParameter(ctx.MAX_TEXTURE_IMAGE_UNITS);
for (var ii = 0; ii < numTextureUnits; ++ii) {
ctx.activeTexture(ctx.TEXTURE0 + ii);
ctx.bindTexture(ctx.TEXTURE_CUBE_MAP, null);
ctx.bindTexture(ctx.TEXTURE_2D, null);
}
ctx.activeTexture(ctx.TEXTURE0);
ctx.useProgram(null);
ctx.bindBuffer(ctx.ARRAY_BUFFER, null);
ctx.bindBuffer(ctx.ELEMENT_ARRAY_BUFFER, null);
ctx.bindFramebuffer(ctx.FRAMEBUFFER, null);
ctx.bindRenderbuffer(ctx.RENDERBUFFER, null);
ctx.disable(ctx.BLEND);
ctx.disable(ctx.CULL_FACE);
ctx.disable(ctx.DEPTH_TEST);
ctx.disable(ctx.DITHER);
ctx.disable(ctx.SCISSOR_TEST);
ctx.blendColor(0, 0, 0, 0);
ctx.blendEquation(ctx.FUNC_ADD);
ctx.blendFunc(ctx.ONE, ctx.ZERO);
ctx.clearColor(0, 0, 0, 0);
ctx.clearDepth(1);
ctx.clearStencil(-1);
ctx.colorMask(true, true, true, true);
ctx.cullFace(ctx.BACK);
ctx.depthFunc(ctx.LESS);
ctx.depthMask(true);
ctx.depthRange(0, 1);
ctx.frontFace(ctx.CCW);
ctx.hint(ctx.GENERATE_MIPMAP_HINT, ctx.DONT_CARE);
ctx.lineWidth(1);
ctx.pixelStorei(ctx.PACK_ALIGNMENT, 4);
ctx.pixelStorei(ctx.UNPACK_ALIGNMENT, 4);
ctx.pixelStorei(ctx.UNPACK_FLIP_Y_WEBGL, false);
ctx.pixelStorei(ctx.UNPACK_PREMULTIPLY_ALPHA_WEBGL, false);
// TODO: Delete this IF.
if (ctx.UNPACK_COLORSPACE_CONVERSION_WEBGL) {
ctx.pixelStorei(ctx.UNPACK_COLORSPACE_CONVERSION_WEBGL, ctx.BROWSER_DEFAULT_WEBGL);
}
ctx.polygonOffset(0, 0);
ctx.sampleCoverage(1, false);
ctx.scissor(0, 0, ctx.canvas.width, ctx.canvas.height);
ctx.stencilFunc(ctx.ALWAYS, 0, 0xFFFFFFFF);
ctx.stencilMask(0xFFFFFFFF);
ctx.stencilOp(ctx.KEEP, ctx.KEEP, ctx.KEEP);
ctx.viewport(0, 0, ctx.canvas.clientWidth, ctx.canvas.clientHeight);
ctx.clear(ctx.COLOR_BUFFER_BIT | ctx.DEPTH_BUFFER_BIT | ctx.STENCIL_BUFFER_BIT);
// TODO: This should NOT be needed but Firefox fails with ‘hint‘
while(ctx.getError());
}
function makeLostContextSimulatingContext(ctx) {
var wrapper_ = {};
var contextId_ = 1;
var contextLost_ = false;
var resourceId_ = 0;
var resourceDb_ = [];
var onLost_ = undefined;
var onRestored_ = undefined;
var nextOnRestored_ = undefined;
// Holds booleans for each GL error so can simulate errors.
var glErrorShadow_ = { };
function isWebGLObject(obj) {
//return false;
return (obj instanceof WebGLBuffer ||
obj instanceof WebGLFramebuffer ||
obj instanceof WebGLProgram ||
obj instanceof WebGLRenderbuffer ||
obj instanceof WebGLShader ||
obj instanceof WebGLTexture);
}
function checkResources(args) {
for (var ii = 0; ii < args.length; ++ii) {
var arg = args[ii];
if (isWebGLObject(arg)) {
return arg.__webglDebugContextLostId__ == contextId_;
}
}
return true;
}
function clearErrors() {
var k = Object.keys(glErrorShadow_);
for (var ii = 0; ii < k.length; ++ii) {
delete glErrorShdow_[k];
}
}
// Makes a function that simulates WebGL when out of context.
function makeLostContextWrapper(ctx, functionName) {
var f = ctx[functionName];
return function() {
// Only call the functions if the context is not lost.
if (!contextLost_) {
if (!checkResources(arguments)) {
glErrorShadow_[ctx.INVALID_OPERATION] = true;
return;
}
var result = f.apply(ctx, arguments);
return result;
}
};
}
for (var propertyName in ctx) {
if (typeof ctx[propertyName] == ‘function‘) {
wrapper_[propertyName] = makeLostContextWrapper(ctx, propertyName);
} else {
wrapper_[propertyName] = ctx[propertyName];
}
}
function makeWebGLContextEvent(statusMessage) {
return {statusMessage: statusMessage};
}
function freeResources() {
for (var ii = 0; ii < resourceDb_.length; ++ii) {
var resource = resourceDb_[ii];
if (resource instanceof WebGLBuffer) {
ctx.deleteBuffer(resource);
} else if (resource instanceof WebctxFramebuffer) {
ctx.deleteFramebuffer(resource);
} else if (resource instanceof WebctxProgram) {
ctx.deleteProgram(resource);
} else if (resource instanceof WebctxRenderbuffer) {
ctx.deleteRenderbuffer(resource);
} else if (resource instanceof WebctxShader) {
ctx.deleteShader(resource);
} else if (resource instanceof WebctxTexture) {
ctx.deleteTexture(resource);
}
}
}
wrapper_.loseContext = function() {
if (!contextLost_) {
contextLost_ = true;
++contextId_;
while (ctx.getError());
clearErrors();
glErrorShadow_[ctx.CONTEXT_LOST_WEBGL] = true;
setTimeout(function() {
if (onLost_) {
onLost_(makeWebGLContextEvent("context lost"));
}
}, 0);
}
};
wrapper_.restoreContext = function() {
if (contextLost_) {
if (onRestored_) {
setTimeout(function() {
freeResources();
resetToInitialState(ctx);
contextLost_ = false;
if (onRestored_) {
var callback = onRestored_;
onRestored_ = nextOnRestored_;
nextOnRestored_ = undefined;
callback(makeWebGLContextEvent("context restored"));
}
}, 0);
} else {
throw "You can not restore the context without a listener"
}
}
};
// Wrap a few functions specially.
wrapper_.getError = function() {
if (!contextLost_) {
var err;
while (err = ctx.getError()) {
glErrorShadow_[err] = true;
}
}
for (var err in glErrorShadow_) {
if (glErrorShadow_[err]) {
delete glErrorShadow_[err];
return err;
}
}
return ctx.NO_ERROR;
};
var creationFunctions = [
"createBuffer",
"createFramebuffer",
"createProgram",
"createRenderbuffer",
"createShader",
"createTexture"
];
for (var ii = 0; ii < creationFunctions.length; ++ii) {
var functionName = creationFunctions[ii];
wrapper_[functionName] = function(f) {
return function() {
if (contextLost_) {
return null;
}
var obj = f.apply(ctx, arguments);
obj.__webglDebugContextLostId__ = contextId_;
resourceDb_.push(obj);
return obj;
};
}(ctx[functionName]);
}
var functionsThatShouldReturnNull = [
"getActiveAttrib",
"getActiveUniform",
"getBufferParameter",
"getContextAttributes",
"getAttachedShaders",
"getFramebufferAttachmentParameter",
"getParameter",
"getProgramParameter",
"getProgramInfoLog",
"getRenderbufferParameter",
"getShaderParameter",
"getShaderInfoLog",
"getShaderSource",
"getTexParameter",
"getUniform",
"getUniformLocation",
"getVertexAttrib"
];
for (var ii = 0; ii < functionsThatShouldReturnNull.length; ++ii) {
var functionName = functionsThatShouldReturnNull[ii];
wrapper_[functionName] = function(f) {
return function() {
if (contextLost_) {
return null;
}
return f.apply(ctx, arguments);
}
}(wrapper_[functionName]);
}
var isFunctions = [
"isBuffer",
"isEnabled",
"isFramebuffer",
"isProgram",
"isRenderbuffer",
"isShader",
"isTexture"
];
for (var ii = 0; ii < isFunctions.length; ++ii) {
var functionName = isFunctions[ii];
wrapper_[functionName] = function(f) {
return function() {
if (contextLost_) {
return false;
}
return f.apply(ctx, arguments);
}
}(wrapper_[functionName]);
}
wrapper_.checkFramebufferStatus = function(f) {
return function() {
if (contextLost_) {
return ctx.FRAMEBUFFER_UNSUPPORTED;
}
return f.apply(ctx, arguments);
};
}(wrapper_.checkFramebufferStatus);
wrapper_.getAttribLocation = function(f) {
return function() {
if (contextLost_) {
return -1;
}
return f.apply(ctx, arguments);
};
}(wrapper_.getAttribLocation);
wrapper_.getVertexAttribOffset = function(f) {
return function() {
if (contextLost_) {
return 0;
}
return f.apply(ctx, arguments);
};
}(wrapper_.getVertexAttribOffset);
wrapper_.isContextLost = function() {
return contextLost_;
};
function wrapEvent(listener) {
if (typeof(listener) == "function") {
return listener;
} else {
return function(info) {
listener.handleEvent(info);
}
}
}
wrapper_.registerOnContextLostListener = function(listener) {
onLost_ = wrapEvent(listener);
};
wrapper_.registerOnContextRestoredListener = function(listener) {
if (contextLost_) {
nextOnRestored_ = wrapEvent(listener);
} else {
onRestored_ = wrapEvent(listener);
}
}
return wrapper_;
}
return {
/**
* Initializes this module. Safe to call more than once.
* @param {!WebGLRenderingContext} ctx A WebGL context. If
* you have more than one context it doesn‘t matter which one
* you pass in, it is only used to pull out constants.
*/
‘init‘: init,
/**
* Returns true or false if value matches any WebGL enum
* @param {*} value Value to check if it might be an enum.
* @return {boolean} True if value matches one of the WebGL defined enums
*/
‘mightBeEnum‘: mightBeEnum,
/**
* Gets an string version of an WebGL enum.
*
* Example:
* WebGLDebugUtil.init(ctx);
* var str = WebGLDebugUtil.glEnumToString(ctx.getError());
*
* @param {number} value Value to return an enum for
* @return {string} The string version of the enum.
*/
‘glEnumToString‘: glEnumToString,
/**
* Converts the argument of a WebGL function to a string.
* Attempts to convert enum arguments to strings.
*
* Example:
* WebGLDebugUtil.init(ctx);
* var str = WebGLDebugUtil.glFunctionArgToString(‘bindTexture‘, 0, gl.TEXTURE_2D);
*
* would return ‘TEXTURE_2D‘
*
* @param {string} functionName the name of the WebGL function.
* @param {number} argumentIndx the index of the argument.
* @param {*} value The value of the argument.
* @return {string} The value as a string.
*/
‘glFunctionArgToString‘: glFunctionArgToString,
/**
* Given a WebGL context returns a wrapped context that calls
* gl.getError after every command and calls a function if the
* result is not NO_ERROR.
*
* You can supply your own function if you want. For example, if you‘d like
* an exception thrown on any GL error you could do this
*
* function throwOnGLError(err, funcName, args) {
* throw WebGLDebugUtils.glEnumToString(err) + " was caused by call to" +
* funcName;
* };
*
* ctx = WebGLDebugUtils.makeDebugContext(
* canvas.getContext("webgl"), throwOnGLError);
*
* @param {!WebGLRenderingContext} ctx The webgl context to wrap.
* @param {!function(err, funcName, args): void} opt_onErrorFunc The function
* to call when gl.getError returns an error. If not specified the default
* function calls console.log with a message.
*/
‘makeDebugContext‘: makeDebugContext,
/**
* Given a WebGL context returns a wrapped context that adds 4
* functions.
*
* ctx.loseContext:
* simulates a lost context event.
*
* ctx.restoreContext:
* simulates the context being restored.
*
* ctx.registerOnContextLostListener(listener):
* lets you register a listener for context lost. Use instead
* of addEventListener(‘webglcontextlostevent‘, listener);
*
* ctx.registerOnContextRestoredListener(listener):
* lets you register a listener for context restored. Use
* instead of addEventListener(‘webglcontextrestored‘,
* listener);
*
* @param {!WebGLRenderingContext} ctx The webgl context to wrap.
*/
‘makeLostContextSimulatingContext‘: makeLostContextSimulatingContext,
/**
* Resets a context to the initial state.
* @param {!WebGLRenderingContext} ctx The webgl context to
* reset.
*/
‘resetToInitialState‘: resetToInitialState
};
}();
webgl-utils.js
/*
* Copyright 2010, Google 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:
*
* * 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.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* 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
* OWNER 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.
*/
/**
* @fileoverview This file contains functions every webgl program will need
* a version of one way or another.
*
* Instead of setting up a context manually it is recommended to
* use. This will check for success or failure. On failure it
* will attempt to present an approriate message to the user.
*
* gl = WebGLUtils.setupWebGL(canvas);
*
* For animated WebGL apps use of setTimeout or setInterval are
* discouraged. It is recommended you structure your rendering
* loop like this.
*
* function render() {
* window.requestAnimationFrame(render, canvas);
*
* // do rendering
* ...
* }
* render();
*
* This will call your rendering function up to the refresh rate
* of your display but will stop rendering if your app is not
* visible.
*/
WebGLUtils = function() {
/**
* Creates the HTLM for a failure message
* @param {string} canvasContainerId id of container of th
* canvas.
* @return {string} The html.
*/
var makeFailHTML = function(msg) {
return ‘‘ +
‘<div style="margin: auto; width:500px;z-index:10000;margin-top:20em;text-align:center;">‘ + msg + ‘</div>‘;
return ‘‘ +
‘<table style="background-color: #8CE; width: 100%; height: 100%;"><tr>‘ +
‘<td align="center">‘ +
‘<div style="display: table-cell; vertical-align: middle;">‘ +
‘<div style="">‘ + msg + ‘</div>‘ +
‘</div>‘ +
‘</td></tr></table>‘;
};
/**
* Mesasge for getting a webgl browser
* @type {string}
*/
var GET_A_WEBGL_BROWSER = ‘‘ +
‘This page requires a browser that supports WebGL.<br/>‘ +
‘<a href="http://get.webgl.org">Click here to upgrade your browser.</a>‘;
/**
* Mesasge for need better hardware
* @type {string}
*/
var OTHER_PROBLEM = ‘‘ +
"It doesn‘t appear your computer can support WebGL.<br/>" +
‘<a href="http://get.webgl.org">Click here for more information.</a>‘;
/**
* Creates a webgl context. If creation fails it will
* change the contents of the container of the <canvas>
* tag to an error message with the correct links for WebGL.
* @param {Element} canvas. The canvas element to create a
* context from.
* @param {WebGLContextCreationAttirbutes} opt_attribs Any
* creation attributes you want to pass in.
* @param {function:(msg)} opt_onError An function to call
* if there is an error during creation.
* @return {WebGLRenderingContext} The created context.
*/
var setupWebGL = function(canvas, opt_attribs, opt_onError) {
function handleCreationError(msg) {
var container = document.getElementsByTagName("body")[0];
//var container = canvas.parentNode;
if (container) {
var str = window.WebGLRenderingContext ?
OTHER_PROBLEM :
GET_A_WEBGL_BROWSER;
if (msg) {
str += "<br/><br/>Status: " + msg;
}
container.innerHTML = makeFailHTML(str);
}
};
opt_onError = opt_onError || handleCreationError;
if (canvas.addEventListener) {
canvas.addEventListener("webglcontextcreationerror", function(event) {
opt_onError(event.statusMessage);
}, false);
}
var context = create3DContext(canvas, opt_attribs);
if (!context) {
if (!window.WebGLRenderingContext) {
opt_onError("");
} else {
opt_onError("");
}
}
return context;
};
/**
* Creates a webgl context.
* @param {!Canvas} canvas The canvas tag to get context
* from. If one is not passed in one will be created.
* @return {!WebGLContext} The created context.
*/
var create3DContext = function(canvas, opt_attribs) {
var names = ["webgl", "experimental-webgl", "webkit-3d", "moz-webgl"];
var context = null;
for (var ii = 0; ii < names.length; ++ii) {
try {
context = canvas.getContext(names[ii], opt_attribs);
} catch(e) {}
if (context) {
break;
}
}
return context;
}
return {
create3DContext: create3DContext,
setupWebGL: setupWebGL
};
}();
/**
* Provides requestAnimationFrame in a cross browser
* way.
*/
if (!window.requestAnimationFrame) {
window.requestAnimationFrame = (function() {
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.oRequestAnimationFrame ||
window.msRequestAnimationFrame ||
function(/* function FrameRequestCallback */ callback, /* DOMElement Element */ element) {
window.setTimeout(callback, 1000/60);
};
})();
}
/** * ERRATA: ‘cancelRequestAnimationFrame‘ renamed to ‘cancelAnimationFrame‘ to reflect an update to the W3C Animation-Timing Spec.
*
* Cancels an animation frame request.
* Checks for cross-browser support, falls back to clearTimeout.
* @param {number} Animation frame request. */
if (!window.cancelAnimationFrame) {
window.cancelAnimationFrame = (window.cancelRequestAnimationFrame ||
window.webkitCancelAnimationFrame || window.webkitCancelRequestAnimationFrame ||
window.mozCancelAnimationFrame || window.mozCancelRequestAnimationFrame ||
window.msCancelAnimationFrame || window.msCancelRequestAnimationFrame ||
window.oCancelAnimationFrame || window.oCancelRequestAnimationFrame ||
window.clearTimeout);
}
主要的HTML文件：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Test</title>
</head>
<body onload="main()">
<!-- create canvas -->
<canvas id="webgl" width="400" height="400">
Please use a browser that supports "canvas"
</canvas>
<!-- needed lib -->
<script src="lib/webgl-utils.js"></script>
<script src="lib/webgl-debug.js"></script>
<script src="lib/cuon-utils.js"></script>
<script src="lib/cuon-matrix.js"></script>
<!-- my webgl source file -->
<script src="test.js"></script>
<script src="shader.js"></script>
</body>
</html>
该HTML主要有三部分，分别是（1）创建Canvas；（2）导入上述库文件；（3）存放自己写的Webgl源码文件。
时间： 2024-10-16 11:44:34