//往后的先不研究 // 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 (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; } //从这里开始 let canvas = document.getElementById("webgl"); let gl = canvas.getContext("webgl"); let VSHADER_SOURCE = 'attribute vec4 a_Position;\n' + 'attribute vec4 a_Color;\n' + 'attribute vec4 a_Normal;\n' + 'uniform mat4 u_MvpMatrix;\n' + 'uniform mat4 u_NormalMatrix;\n' + 'uniform vec3 u_LightDirection;\n' + 'varying vec4 v_Color;\n' + 'void main() {\n' + ' gl_Position = u_MvpMatrix * a_Position;\n' + ' vec4 normal = u_NormalMatrix * a_Normal;\n' + ' float nDotL = max(dot(u_LightDirection, normalize(normal.xyz)), 0.0);\n' + ' v_Color = vec4(a_Color.xyz * nDotL, a_Color.a);\n' + '}\n'; let FSHADER_SOURCE = 'precision mediump float;' + 'varying vec4 v_Color;\n' + 'void main() {\n' + ' gl_FragColor = v_Color;\n' + '}\n'; // Initialize shaders if (!initShaders(gl, VSHADER_SOURCE, FSHADER_SOURCE)) { console.log('Failed to intialize shaders.'); return; } // var n = initVertexBuffers(gl); if (n < 0) { console.log('Failed to set the vertex information'); return; } // Set the clear color and enable the depth test gl.clearColor(0, 0, 0, 1); gl.enable(gl.DEPTH_TEST); // Get the storage locations of uniform variables and so on var u_MvpMatrix = gl.getUniformLocation(gl.program, 'u_MvpMatrix'); var u_NormalMatrix = gl.getUniformLocation(gl.program, 'u_NormalMatrix'); var u_LightDirection = gl.getUniformLocation(gl.program, 'u_LightDirection'); if (!u_MvpMatrix || !u_NormalMatrix || !u_LightDirection) { console.log('Failed to get the storage location'); return; } var vpMatrix = new Matrix4(); // View projection matrix // Calculate the view projection matrix vpMatrix.setPerspective(30, canvas.width/canvas.height, 1, 100); vpMatrix.lookAt(3, 3, 7, 0, 0, 0, 0, 1, 0); // Set the light direction (in the world coordinate) var lightDirection = new Vector3([0.5, 3.0, 4.0]); lightDirection.normalize(); // Normalize gl.uniform3fv(u_LightDirection, lightDirection.elements); var currentAngle = 0.0; // Current rotation angle var modelMatrix = new Matrix4(); // Model matrix var mvpMatrix = new Matrix4(); // Model view projection matrix var normalMatrix = new Matrix4(); // Transformation matrix for normals var tick = function() { currentAngle = animate(currentAngle); // Update the rotation angle // Calculate the model matrix modelMatrix.setRotate(currentAngle, 0, 1, 0); // Rotate around the y-axis mvpMatrix.set(vpMatrix).multiply(modelMatrix); gl.uniformMatrix4fv(u_MvpMatrix, false, mvpMatrix.elements); // Pass the matrix to transform the normal based on the model matrix to u_NormalMatrix normalMatrix.setInverseOf(modelMatrix); normalMatrix.transpose(); gl.uniformMatrix4fv(u_NormalMatrix, false, normalMatrix.elements); // Clear color and depth buffer gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT); // Draw the cube gl.drawElements(gl.TRIANGLES, n, gl.UNSIGNED_BYTE, 0); requestAnimationFrame(tick, canvas); // Request that the browser ?calls tick }; function draw(gl, n, angle, vpMatrix, u_MvpMatrix, u_NormalMatrix) { } function draw(gl, n, angle, vpMatrix, u_MvpMatrix, u_NormalMatrix) { } function initVertexBuffers(gl) { // Create a cube // v6----- v5 // /| /| // v1------v0| // | | | | // | |v7---|-|v4 // |/ |/ // v2------v3 // Coordinates var vertices = new Float32Array([ 1.0, 1.0, 1.0, -1.0, 1.0, 1.0, -1.0,-1.0, 1.0, 1.0,-1.0, 1.0, // v0-v1-v2-v3 front 1.0, 1.0, 1.0, 1.0,-1.0, 1.0, 1.0,-1.0,-1.0, 1.0, 1.0,-1.0, // v0-v3-v4-v5 right 1.0, 1.0, 1.0, 1.0, 1.0,-1.0, -1.0, 1.0,-1.0, -1.0, 1.0, 1.0, // v0-v5-v6-v1 up -1.0, 1.0, 1.0, -1.0, 1.0,-1.0, -1.0,-1.0,-1.0, -1.0,-1.0, 1.0, // v1-v6-v7-v2 left -1.0,-1.0,-1.0, 1.0,-1.0,-1.0, 1.0,-1.0, 1.0, -1.0,-1.0, 1.0, // v7-v4-v3-v2 down 1.0,-1.0,-1.0, -1.0,-1.0,-1.0, -1.0, 1.0,-1.0, 1.0, 1.0,-1.0 // v4-v7-v6-v5 back ]); // Colors var colors = new Float32Array([ 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, // v0-v1-v2-v3 front 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, // v0-v3-v4-v5 right 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, // v0-v5-v6-v1 up 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, // v1-v6-v7-v2 left 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, // v7-v4-v3-v2 down 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0 // v4-v7-v6-v5 back ]); // Normal var normals = new Float32Array([ 0.0, 0.0, 1.0, 0.0, 0.0, 1.0, 0.0, 0.0, 1.0, 0.0, 0.0, 1.0, // v0-v1-v2-v3 front 1.0, 0.0, 0.0, 1.0, 0.0, 0.0, 1.0, 0.0, 0.0, 1.0, 0.0, 0.0, // v0-v3-v4-v5 right 0.0, 1.0, 0.0, 0.0, 1.0, 0.0, 0.0, 1.0, 0.0, 0.0, 1.0, 0.0, // v0-v5-v6-v1 up -1.0, 0.0, 0.0, -1.0, 0.0, 0.0, -1.0, 0.0, 0.0, -1.0, 0.0, 0.0, // v1-v6-v7-v2 left 0.0,-1.0, 0.0, 0.0,-1.0, 0.0, 0.0,-1.0, 0.0, 0.0,-1.0, 0.0, // v7-v4-v3-v2 down 0.0, 0.0,-1.0, 0.0, 0.0,-1.0, 0.0, 0.0,-1.0, 0.0, 0.0,-1.0 // v4-v7-v6-v5 back ]); // Indices of the vertices var indices = new Uint8Array([ 0, 1, 2, 0, 2, 3, // front 4, 5, 6, 4, 6, 7, // right 8, 9,10, 8,10,11, // up 12,13,14, 12,14,15, // left 16,17,18, 16,18,19, // down 20,21,22, 20,22,23 // back ]); // Write the vertex property to buffers (coordinates, colors and normals) if (!initArrayBuffer(gl, 'a_Position', vertices, 3, gl.FLOAT)) return -1; if (!initArrayBuffer(gl, 'a_Color', colors, 3, gl.FLOAT)) return -1; if (!initArrayBuffer(gl, 'a_Normal', normals, 3, gl.FLOAT)) return -1; // Unbind the buffer object gl.bindBuffer(gl.ARRAY_BUFFER, null); // Write the indices to the buffer object var indexBuffer = gl.createBuffer(); if (!indexBuffer) { console.log('Failed to create the buffer object'); return false; } gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, indexBuffer); gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, indices, gl.STATIC_DRAW); return indices.length; } function initArrayBuffer(gl, attribute, data, num, type) { // Create a buffer object var buffer = gl.createBuffer(); if (!buffer) { console.log('Failed to create the buffer object'); return false; } // Write date into the buffer object gl.bindBuffer(gl.ARRAY_BUFFER, buffer); gl.bufferData(gl.ARRAY_BUFFER, data, gl.STATIC_DRAW); // Assign the buffer object to the attribute variable var a_attribute = gl.getAttribLocation(gl.program, attribute); if (a_attribute < 0) { console.log('Failed to get the storage location of ' + attribute); return false; } gl.vertexAttribPointer(a_attribute, num, type, false, 0, 0); // Enable the assignment of the buffer object to the attribute variable gl.enableVertexAttribArray(a_attribute); return true; } // Rotation angle (degrees/second) var ANGLE_STEP = 30.0; // Last time that this function was called var g_last = Date.now(); function animate(angle) { // Calculate the elapsed time var now = Date.now(); var elapsed = now - g_last; g_last = now; // Update the current rotation angle (adjusted by the elapsed time) var newAngle = angle + (ANGLE_STEP * elapsed) / 1000.0; return newAngle %= 360; } tick();
<canvas id="webgl" width="400" height="400"></canvas>