/** * Class representing a path. * Designed to be compatible with [CanvasPathMethods](http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#canvaspathmethods) * and will hopefully be replaced by the browsers' implementation of the Path object. */Ext.define('Ext.draw.Path', { requires: ['Ext.draw.Draw'], statics: { pathRe: /,?([achlmqrstvxz]),?/gi, pathRe2: /-/gi, pathSplitRe: /\s|,/g }, svgString: '', /** * Create a path from pathString. * @constructor * @param {String} pathString */ constructor: function (pathString) { var me = this; me.commands = []; // Stores command letters from the SVG path data ('d' attribute). me.params = []; // Stores command parameters from the SVG path data. // All command parameters are actually point coordinates as the only commands used // are the M, L, C, Z. This makes path transformations and hit testing easier. // Arcs are approximated using cubic Bezier curves, H and S commands are translated // to L commands and relative commands are translated to their absolute versions. me.cursor = null; me.startX = 0; me.startY = 0; if (pathString) { me.fromSvgString(pathString); } }, /** * Clear the path. */ clear: function () { var me = this; me.params.length = 0; me.commands.length = 0; me.cursor = null; me.startX = 0; me.startY = 0; me.dirt(); }, /** * @private */ dirt: function () { this.svgString = ''; }, /** * Move to a position. * @param {Number} x * @param {Number} y */ moveTo: function (x, y) { var me = this; if (!me.cursor) { me.cursor = [x, y]; } me.params.push(x, y); me.commands.push('M'); me.startX = x; me.startY = y; me.cursor[0] = x; me.cursor[1] = y; me.dirt(); }, /** * A straight line to a position. * @param {Number} x * @param {Number} y */ lineTo: function (x, y) { var me = this; if (!me.cursor) { me.cursor = [x, y]; me.params.push(x, y); me.commands.push('M'); } else { me.params.push(x, y); me.commands.push('L'); } me.cursor[0] = x; me.cursor[1] = y; me.dirt(); }, /** * A cubic bezier curve to a position. * @param {Number} cx1 * @param {Number} cy1 * @param {Number} cx2 * @param {Number} cy2 * @param {Number} x * @param {Number} y */ bezierCurveTo: function (cx1, cy1, cx2, cy2, x, y) { var me = this; if (!me.cursor) { me.moveTo(cx1, cy1); } me.params.push(cx1, cy1, cx2, cy2, x, y); me.commands.push('C'); me.cursor[0] = x; me.cursor[1] = y; me.dirt(); }, /** * A quadratic bezier curve to a position. * @param {Number} cx * @param {Number} cy * @param {Number} x * @param {Number} y */ quadraticCurveTo: function (cx, cy, x, y) { var me = this; if (!me.cursor) { me.moveTo(cx, cy); } me.bezierCurveTo( (2 * cx + me.cursor[0]) / 3, (2 * cy + me.cursor[1]) / 3, (2 * cx + x) / 3, (2 * cy + y) / 3, x, y ); }, /** * Close this path with a straight line. */ closePath: function () { var me = this; if (me.cursor) { me.commands.push('Z'); me.dirt(); } }, /** * Create a elliptic arc curve compatible with SVG's arc to instruction. * * The curve start from (`x1`, `y1`) and ends at (`x2`, `y2`). The ellipse * has radius `rx` and `ry` and a rotation of `rotation`. * @param {Number} x1 * @param {Number} y1 * @param {Number} x2 * @param {Number} y2 * @param {Number} [rx] * @param {Number} [ry] * @param {Number} [rotation] */ arcTo: function (x1, y1, x2, y2, rx, ry, rotation) { var me = this; if (ry === undefined) { ry = rx; } if (rotation === undefined) { rotation = 0; } if (!me.cursor) { me.moveTo(x1, y1); return; } if (rx === 0 || ry === 0) { me.lineTo(x1, y1); return; } x2 -= x1; y2 -= y1; var x0 = me.cursor[0] - x1, y0 = me.cursor[1] - y1, area = x2 * y0 - y2 * x0, cos, sin, xx, yx, xy, yy, l0 = Math.sqrt(x0 * x0 + y0 * y0), l2 = Math.sqrt(x2 * x2 + y2 * y2), dist, cx, cy; // cos rx, -sin ry , x1 - cos rx x1 + ry sin y1 // sin rx, cos ry, -rx sin x1 + y1 - cos ry y1 if (area === 0) { me.lineTo(x1, y1); return; } if (ry !== rx) { cos = Math.cos(rotation); sin = Math.sin(rotation); xx = cos / rx; yx = sin / ry; xy = -sin / rx; yy = cos / ry; var temp = xx * x0 + yx * y0; y0 = xy * x0 + yy * y0; x0 = temp; temp = xx * x2 + yx * y2; y2 = xy * x2 + yy * y2; x2 = temp; } else { x0 /= rx; y0 /= ry; x2 /= rx; y2 /= ry; } cx = x0 * l2 + x2 * l0; cy = y0 * l2 + y2 * l0; dist = 1 / (Math.sin(Math.asin(Math.abs(area) / (l0 * l2)) * 0.5) * Math.sqrt(cx * cx + cy * cy)); cx *= dist; cy *= dist; var k0 = (cx * x0 + cy * y0) / (x0 * x0 + y0 * y0), k2 = (cx * x2 + cy * y2) / (x2 * x2 + y2 * y2); var cosStart = x0 * k0 - cx, sinStart = y0 * k0 - cy, cosEnd = x2 * k2 - cx, sinEnd = y2 * k2 - cy, startAngle = Math.atan2(sinStart, cosStart), endAngle = Math.atan2(sinEnd, cosEnd); if (area > 0) { if (endAngle < startAngle) { endAngle += Math.PI * 2; } } else { if (startAngle < endAngle) { startAngle += Math.PI * 2; } } if (ry !== rx) { cx = cos * cx * rx - sin * cy * ry + x1; cy = sin * cy * ry + cos * cy * ry + y1; me.lineTo(cos * rx * cosStart - sin * ry * sinStart + cx, sin * rx * cosStart + cos * ry * sinStart + cy); me.ellipse(cx, cy, rx, ry, rotation, startAngle, endAngle, area < 0); } else { cx = cx * rx + x1; cy = cy * ry + y1; me.lineTo(rx * cosStart + cx, ry * sinStart + cy); me.ellipse(cx, cy, rx, ry, rotation, startAngle, endAngle, area < 0); } }, /** * Create an elliptic arc. * * See [the whatwg reference of ellipse](http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#dom-context-2d-ellipse). * * @param {Number} cx * @param {Number} cy * @param {Number} radiusX * @param {Number} radiusY * @param {Number} rotation * @param {Number} startAngle * @param {Number} endAngle * @param {Number} anticlockwise */ ellipse: function (cx, cy, radiusX, radiusY, rotation, startAngle, endAngle, anticlockwise) { var me = this, params = me.params, start = params.length, count, i, j; if (endAngle - startAngle >= Math.PI * 2) { me.ellipse(cx, cy, radiusX, radiusY, rotation, startAngle, startAngle + Math.PI, anticlockwise); me.ellipse(cx, cy, radiusX, radiusY, rotation, startAngle + Math.PI, endAngle, anticlockwise); return; } if (!anticlockwise) { if (endAngle < startAngle) { endAngle += Math.PI * 2; } count = me.approximateArc(params, cx, cy, radiusX, radiusY, rotation, startAngle, endAngle); } else { if (startAngle < endAngle) { startAngle += Math.PI * 2; } count = me.approximateArc(params, cx, cy, radiusX, radiusY, rotation, endAngle, startAngle); for (i = start, j = params.length - 2; i < j; i += 2, j -= 2) { var temp = params[i]; params[i] = params[j]; params[j] = temp; temp = params[i + 1]; params[i + 1] = params[j + 1]; params[j + 1] = temp; } } if (!me.cursor) { me.cursor = [params[params.length - 2], params[params.length - 1]]; me.commands.push('M'); } else { me.cursor[0] = params[params.length - 2]; me.cursor[1] = params[params.length - 1]; me.commands.push('L'); } for (i = 2; i < count; i += 6) { me.commands.push('C'); } me.dirt(); }, /** * Create an circular arc. * * @param {Number} x * @param {Number} y * @param {Number} radius * @param {Number} startAngle * @param {Number} endAngle * @param {Number} anticlockwise */ arc: function (x, y, radius, startAngle, endAngle, anticlockwise) { this.ellipse(x, y, radius, radius, 0, startAngle, endAngle, anticlockwise); }, /** * Draw a rectangle and close it. * * @param {Number} x * @param {Number} y * @param {Number} width * @param {Number} height */ rect: function (x, y, width, height) { if (width == 0 || height == 0) { return; } var me = this; me.moveTo(x, y); me.lineTo(x + width, y); me.lineTo(x + width, y + height); me.lineTo(x, y + height); me.closePath(); }, /** * @private * @param {Array} result * @param {Number} cx * @param {Number} cy * @param {Number} rx * @param {Number} ry * @param {Number} phi * @param {Number} theta1 * @param {Number} theta2 * @return {Number} */ approximateArc: function (result, cx, cy, rx, ry, phi, theta1, theta2) { var cosPhi = Math.cos(phi), sinPhi = Math.sin(phi), cosTheta1 = Math.cos(theta1), sinTheta1 = Math.sin(theta1), xx = cosPhi * cosTheta1 * rx - sinPhi * sinTheta1 * ry, yx = -cosPhi * sinTheta1 * rx - sinPhi * cosTheta1 * ry, xy = sinPhi * cosTheta1 * rx + cosPhi * sinTheta1 * ry, yy = -sinPhi * sinTheta1 * rx + cosPhi * cosTheta1 * ry, rightAngle = Math.PI / 2, count = 2, exx = xx, eyx = yx, exy = xy, eyy = yy, rho = 0.547443256150549, temp, y1, x3, y3, x2, y2; theta2 -= theta1; if (theta2 < 0) { theta2 += Math.PI * 2; } result.push(xx + cx, xy + cy); while (theta2 >= rightAngle) { result.push( exx + eyx * rho + cx, exy + eyy * rho + cy, exx * rho + eyx + cx, exy * rho + eyy + cy, eyx + cx, eyy + cy ); count += 6; theta2 -= rightAngle; temp = exx; exx = eyx; eyx = -temp; temp = exy; exy = eyy; eyy = -temp; } if (theta2) { y1 = (0.3294738052815987 + 0.012120855841304373 * theta2) * theta2; x3 = Math.cos(theta2); y3 = Math.sin(theta2); x2 = x3 + y1 * y3; y2 = y3 - y1 * x3; result.push( exx + eyx * y1 + cx, exy + eyy * y1 + cy, exx * x2 + eyx * y2 + cx, exy * x2 + eyy * y2 + cy, exx * x3 + eyx * y3 + cx, exy * x3 + eyy * y3 + cy ); count += 6; } return count; }, /** * [http://www.w3.org/TR/SVG/implnote.html#ArcImplementationNotes](http://www.w3.org/TR/SVG/implnote.html#ArcImplementationNotes) * @param {Number} rx * @param {Number} ry * @param {Number} rotation Differ from svg spec, this is radian. * @param {Number} fA * @param {Number} fS * @param {Number} x2 * @param {Number} y2 */ arcSvg: function (rx, ry, rotation, fA, fS, x2, y2) { if (rx < 0) { rx = -rx; } if (ry < 0) { ry = -ry; } var me = this, x1 = me.cursor[0], y1 = me.cursor[1], hdx = (x1 - x2) / 2, hdy = (y1 - y2) / 2, cosPhi = Math.cos(rotation), sinPhi = Math.sin(rotation), xp = hdx * cosPhi + hdy * sinPhi, yp = -hdx * sinPhi + hdy * cosPhi, ratX = xp / rx, ratY = yp / ry, lambda = ratX * ratX + ratY * ratY, cx = (x1 + x2) * 0.5, cy = (y1 + y2) * 0.5, cpx = 0, cpy = 0; if (lambda >= 1) { lambda = Math.sqrt(lambda); rx *= lambda; ry *= lambda; // me gives lambda == cpx == cpy == 0; } else { lambda = Math.sqrt(1 / lambda - 1); if (fA === fS) { lambda = -lambda; } cpx = lambda * rx * ratY; cpy = -lambda * ry * ratX; cx += cosPhi * cpx - sinPhi * cpy; cy += sinPhi * cpx + cosPhi * cpy; } var theta1 = Math.atan2((yp - cpy) / ry, (xp - cpx) / rx), deltaTheta = Math.atan2((-yp - cpy) / ry, (-xp - cpx) / rx) - theta1; if (fS) { if (deltaTheta <= 0) { deltaTheta += Math.PI * 2; } } else { if (deltaTheta >= 0) { deltaTheta -= Math.PI * 2; } } me.ellipse(cx, cy, rx, ry, rotation, theta1, theta1 + deltaTheta, 1 - fS); }, /** * Feed the path from svg path string. * @param {String} pathString */ fromSvgString: function (pathString) { if (!pathString) { return; } var me = this, parts, paramCounts = { a: 7, c: 6, h: 1, l: 2, m: 2, q: 4, s: 4, t: 2, v: 1, z: 0, A: 7, C: 6, H: 1, L: 2, M: 2, Q: 4, S: 4, T: 2, V: 1, Z: 0 }, lastCommand = '', lastControlX, lastControlY, lastX = 0, lastY = 0, part = false, i, partLength, relative; // Split the string to items. if (Ext.isString(pathString)) { parts = pathString.replace(Ext.draw.Path.pathRe, " $1 ").replace(Ext.draw.Path.pathRe2, " -").split(Ext.draw.Path.pathSplitRe); } else if (Ext.isArray(pathString)) { parts = pathString.join(',').split(Ext.draw.Path.pathSplitRe); } // Remove empty entries for (i = 0, partLength = 0; i < parts.length; i++) { if (parts[i] !== '') { parts[partLength++] = parts[i]; } } parts.length = partLength; me.clear(); for (i = 0; i < parts.length;) { lastCommand = part; part = parts[i]; relative = (part.toUpperCase() !== part); i++; switch (part) { case 'M': me.moveTo(lastX = +parts[i], lastY = +parts[i + 1]); i += 2; while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.lineTo(lastX = +parts[i], lastY = +parts[i + 1]); i += 2; } break; case 'L': me.lineTo(lastX = +parts[i], lastY = +parts[i + 1]); i += 2; while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.lineTo(lastX = +parts[i], lastY = +parts[i + 1]); i += 2; } break; case 'A': while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.arcSvg( +parts[i], +parts[i + 1], +parts[i + 2] * Math.PI / 180, +parts[i + 3], +parts[i + 4], lastX = +parts[i + 5], lastY = +parts[i + 6]); i += 7; } break; case 'C': while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.bezierCurveTo( +parts[i ], +parts[i + 1], lastControlX = +parts[i + 2], lastControlY = +parts[i + 3], lastX = +parts[i + 4], lastY = +parts[i + 5]); i += 6; } break; case 'Z': me.closePath(); break; case 'm': me.moveTo(lastX += +parts[i], lastY += +parts[i + 1]); i += 2; while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.lineTo(lastX += +parts[i], lastY += +parts[i + 1]); i += 2; } break; case 'l': me.lineTo(lastX += +parts[i], lastY += +parts[i + 1]); i += 2; while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.lineTo(lastX += +parts[i], lastY += +parts[i + 1]); i += 2; } break; case 'a': while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.arcSvg( +parts[i], +parts[i + 1], +parts[i + 2] * Math.PI / 180, +parts[i + 3], +parts[i + 4], lastX += +parts[i + 5], lastY += +parts[i + 6]); i += 7; } break; case 'c': while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.bezierCurveTo(lastX + (+parts[i]), lastY + (+parts[i + 1]), lastControlX = lastX + (+parts[i + 2]), lastControlY = lastY + (+parts[i + 3]), lastX += +parts[i + 4], lastY += +parts[i + 5]); i += 6; } break; case 'z': me.closePath(); break; case 's': if (!(lastCommand === 'c' || lastCommand === 'C' || lastCommand === 's' || lastCommand === 'S')) { lastControlX = lastX; lastControlY = lastY; } while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.bezierCurveTo( lastX + lastX - lastControlX, lastY + lastY - lastControlY, lastControlX = lastX + (+parts[i]), lastControlY = lastY + (+parts[i + 1]), lastX += +parts[i + 2], lastY += +parts[i + 3]); i += 4; } break; case 'S': if (!(lastCommand === 'c' || lastCommand === 'C' || lastCommand === 's' || lastCommand === 'S')) { lastControlX = lastX; lastControlY = lastY; } while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.bezierCurveTo( lastX + lastX - lastControlX, lastY + lastY - lastControlY, lastControlX = +parts[i], lastControlY = +parts[i + 1], lastX = (+parts[i + 2]), lastY = (+parts[i + 3])); i += 4; } break; case 'q': while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.quadraticCurveTo( lastControlX = lastX + (+parts[i]), lastControlY = lastY + (+parts[i + 1]), lastX += +parts[i + 2], lastY += +parts[i + 3]); i += 4; } break; case 'Q': while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.quadraticCurveTo( lastControlX = +parts[i], lastControlY = +parts[i + 1], lastX = +parts[i + 2], lastY = +parts[i + 3]); i += 4; } break; case 't': if (!(lastCommand === 'q' || lastCommand === 'Q' || lastCommand === 't' || lastCommand === 'T')) { lastControlX = lastX; lastControlY = lastY; } while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.quadraticCurveTo( lastControlX = lastX + lastX - lastControlX, lastControlY = lastY + lastY - lastControlY, lastX += +parts[i + 1], lastY += +parts[i + 2]); i += 2; } break; case 'T': if (!(lastCommand === 'q' || lastCommand === 'Q' || lastCommand === 't' || lastCommand === 'T')) { lastControlX = lastX; lastControlY = lastY; } while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.quadraticCurveTo( lastControlX = lastX + lastX - lastControlX, lastControlY = lastY + lastY - lastControlY, lastX = (+parts[i + 1]), lastY = (+parts[i + 2])); i += 2; } break; case 'h': while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.lineTo(lastX += +parts[i], lastY); i++; } break; case 'H': while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.lineTo(lastX = +parts[i], lastY); i++; } break; case 'v': while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.lineTo(lastX, lastY += +parts[i]); i++; } break; case 'V': while (i < partLength && !paramCounts.hasOwnProperty(parts[i])) { me.lineTo(lastX, lastY = +parts[i]); i++; } break; } } }, /** * Clone this path. * @return {Ext.draw.Path} */ clone: function () { var me = this, path = new Ext.draw.Path(); path.params = me.params.slice(0); path.commands = me.commands.slice(0); path.cursor = me.cursor ? me.cursor.slice(0) : null; path.startX = me.startX; path.startY = me.startY; path.svgString = me.svgString; return path; }, /** * Transform the current path by a matrix. * @param {Ext.draw.Matrix} matrix */ transform: function (matrix) { if (matrix.isIdentity()) { return; } var xx = matrix.getXX(), yx = matrix.getYX(), dx = matrix.getDX(), xy = matrix.getXY(), yy = matrix.getYY(), dy = matrix.getDY(), params = this.params, i = 0, ln = params.length, x, y; for (; i < ln; i += 2) { x = params[i]; y = params[i + 1]; params[i] = x * xx + y * yx + dx; params[i + 1] = x * xy + y * yy + dy; } this.dirt(); }, /** * Get the bounding box of this matrix. * @param {Object} [target] Optional object to receive the result. * * @return {Object} Object with x, y, width and height */ getDimension: function (target) { if (!target) { target = {}; } if (!this.commands || !this.commands.length) { target.x = 0; target.y = 0; target.width = 0; target.height = 0; return target; } target.left = Infinity; target.top = Infinity; target.right = -Infinity; target.bottom = -Infinity; var i = 0, j = 0, commands = this.commands, params = this.params, ln = commands.length, x, y; for (; i < ln; i++) { switch (commands[i]) { case 'M': case 'L': x = params[j]; y = params[j + 1]; target.left = Math.min(x, target.left); target.top = Math.min(y, target.top); target.right = Math.max(x, target.right); target.bottom = Math.max(y, target.bottom); j += 2; break; case 'C': this.expandDimension(target, x, y, params[j], params[j + 1], params[j + 2], params[j + 3], x = params[j + 4], y = params[j + 5]); j += 6; break; } } target.x = target.left; target.y = target.top; target.width = target.right - target.left; target.height = target.bottom - target.top; return target; }, /** * Get the bounding box as if the path is transformed by a matrix. * * @param {Ext.draw.Matrix} matrix * @param {Object} [target] Optional object to receive the result. * * @return {Object} An object with x, y, width and height. */ getDimensionWithTransform: function (matrix, target) { if (!this.commands || !this.commands.length) { if (!target) { target = {}; } target.x = 0; target.y = 0; target.width = 0; target.height = 0; return target; } target.left = Infinity; target.top = Infinity; target.right = -Infinity; target.bottom = -Infinity; var xx = matrix.getXX(), yx = matrix.getYX(), dx = matrix.getDX(), xy = matrix.getXY(), yy = matrix.getYY(), dy = matrix.getDY(), i = 0, j = 0, commands = this.commands, params = this.params, ln = commands.length, x, y; for (; i < ln; i++) { switch (commands[i]) { case 'M': case 'L': x = params[j] * xx + params[j + 1] * yx + dx; y = params[j] * xy + params[j + 1] * yy + dy; target.left = Math.min(x, target.left); target.top = Math.min(y, target.top); target.right = Math.max(x, target.right); target.bottom = Math.max(y, target.bottom); j += 2; break; case 'C': this.expandDimension(target, x, y, params[j] * xx + params[j + 1] * yx + dx, params[j] * xy + params[j + 1] * yy + dy, params[j + 2] * xx + params[j + 3] * yx + dx, params[j + 2] * xy + params[j + 3] * yy + dy, x = params[j + 4] * xx + params[j + 5] * yx + dx, y = params[j + 4] * xy + params[j + 5] * yy + dy); j += 6; break; } } if (!target) { target = {}; } target.x = target.left; target.y = target.top; target.width = target.right - target.left; target.height = target.bottom - target.top; return target; }, /** * @private * Expand the rect by the bbox of a bezier curve. * * @param {Object} target * @param {Number} x1 * @param {Number} y1 * @param {Number} cx1 * @param {Number} cy1 * @param {Number} cx2 * @param {Number} cy2 * @param {Number} x2 * @param {Number} y2 */ expandDimension: function (target, x1, y1, cx1, cy1, cx2, cy2, x2, y2) { var me = this, l = target.left, r = target.right, t = target.top, b = target.bottom, dim = me.dim || (me.dim = []); me.curveDimension(x1, cx1, cx2, x2, dim); l = Math.min(l, dim[0]); r = Math.max(r, dim[1]); me.curveDimension(y1, cy1, cy2, y2, dim); t = Math.min(t, dim[0]); b = Math.max(b, dim[1]); target.left = l; target.right = r; target.top = t; target.bottom = b; }, /** * @private * Determine the curve * @param {Number} a * @param {Number} b * @param {Number} c * @param {Number} d * @param {Number} dim */ curveDimension: function (a, b, c, d, dim) { var qa = 3 * (-a + 3 * (b - c) + d), qb = 6 * (a - 2 * b + c), qc = -3 * (a - b), x, y, min = Math.min(a, d), max = Math.max(a, d), delta; if (qa === 0) { if (qb === 0) { dim[0] = min; dim[1] = max; return; } else { x = -qc / qb; if (0 < x && x < 1) { y = this.interpolate(a, b, c, d, x); min = Math.min(min, y); max = Math.max(max, y); } } } else { delta = qb * qb - 4 * qa * qc; if (delta >= 0) { delta = Math.sqrt(delta); x = (delta - qb) / 2 / qa; if (0 < x && x < 1) { y = this.interpolate(a, b, c, d, x); min = Math.min(min, y); max = Math.max(max, y); } if (delta > 0) { x -= delta / qa; if (0 < x && x < 1) { y = this.interpolate(a, b, c, d, x); min = Math.min(min, y); max = Math.max(max, y); } } } } dim[0] = min; dim[1] = max; }, /** * @private * * Returns `a * (1 - t) ^ 3 + 3 * b (1 - t) ^ 2 * t + 3 * c (1 - t) * t ^ 3 + d * t ^ 3`. * * @param {Number} a * @param {Number} b * @param {Number} c * @param {Number} d * @param {Number} t * @return {Number} */ interpolate: function (a, b, c, d, t) { if (t === 0) { return a; } if (t === 1) { return d; } var rate = (1 - t) / t; return t * t * t * (d + rate * (3 * c + rate * (3 * b + rate * a))); }, /** * Reconstruct path from cubic bezier curve stripes. * @param {Array} stripes */ fromStripes: function (stripes) { var me = this, i = 0, ln = stripes.length, j, ln2, stripe; me.clear(); for (; i < ln; i++) { stripe = stripes[i]; me.params.push.apply(me.params, stripe); me.commands.push('M'); for (j = 2, ln2 = stripe.length; j < ln2; j += 6) { me.commands.push('C'); } } if (!me.cursor) { me.cursor = []; } me.cursor[0] = me.params[me.params.length - 2]; me.cursor[1] = me.params[me.params.length - 1]; me.dirt(); }, /** * Convert path to bezier curve stripes. * @param {Array} [target] The optional array to receive the result. * @return {Array} */ toStripes: function (target) { var stripes = target || [], curr, x, y, lastX, lastY, startX, startY, i, j, commands = this.commands, params = this.params, ln = commands.length; for (i = 0, j = 0; i < ln; i++) { switch (commands[i]) { case 'M': curr = [startX = lastX = params[j++], startY = lastY = params[j++]]; stripes.push(curr); break; case 'L': x = params[j++]; y = params[j++]; curr.push((lastX + lastX + x) / 3, (lastY + lastY + y) / 3, (lastX + x + x) / 3, (lastY + y + y) / 3, lastX = x, lastY = y); break; case 'C': curr.push(params[j++], params[j++], params[j++], params[j++], lastX = params[j++], lastY = params[j++]); break; case 'Z': x = startX; y = startY; curr.push((lastX + lastX + x) / 3, (lastY + lastY + y) / 3, (lastX + x + x) / 3, (lastY + y + y) / 3, lastX = x, lastY = y); break; } } return stripes; }, /** * @private * Update cache for svg string of this path. */ updateSvgString: function () { var result = [], commands = this.commands, params = this.params, ln = commands.length, i = 0, j = 0; for (; i < ln; i++) { switch (commands[i]) { case 'M': result.push('M' + params[j] + ',' + params[j + 1]); j += 2; break; case 'L': result.push('L' + params[j] + ',' + params[j + 1]); j += 2; break; case 'C': result.push('C' + params[j] + ',' + params[j + 1] + ' ' + params[j + 2] + ',' + params[j + 3] + ' ' + params[j + 4] + ',' + params[j + 5]); j += 6; break; case 'Z': result.push('Z'); break; } } this.svgString = result.join(''); }, /** * Return an svg path string for this path. * @return {String} */ toString: function () { if (!this.svgString) { this.updateSvgString(); } return this.svgString; }});