var PathProxy = require("../core/PathProxy"); var line = require("./line"); var cubic = require("./cubic"); var quadratic = require("./quadratic"); var arc = require("./arc"); var _util = require("./util"); var normalizeRadian = _util.normalizeRadian; var curve = require("../core/curve"); var windingLine = require("./windingLine"); var CMD = PathProxy.CMD; var PI2 = Math.PI * 2; var EPSILON = 1e-4; function isAroundEqual(a, b) { return Math.abs(a - b) < EPSILON; } // 临时数组 var roots = [-1, -1, -1]; var extrema = [-1, -1]; function swapExtrema() { var tmp = extrema[0]; extrema[0] = extrema[1]; extrema[1] = tmp; } function windingCubic(x0, y0, x1, y1, x2, y2, x3, y3, x, y) { // Quick reject if (y > y0 && y > y1 && y > y2 && y > y3 || y < y0 && y < y1 && y < y2 && y < y3) { return 0; } var nRoots = curve.cubicRootAt(y0, y1, y2, y3, y, roots); if (nRoots === 0) { return 0; } else { var w = 0; var nExtrema = -1; var y0_; var y1_; for (var i = 0; i < nRoots; i++) { var t = roots[i]; // Avoid winding error when intersection point is the connect point of two line of polygon var unit = t === 0 || t === 1 ? 0.5 : 1; var x_ = curve.cubicAt(x0, x1, x2, x3, t); if (x_ < x) { // Quick reject continue; } if (nExtrema < 0) { nExtrema = curve.cubicExtrema(y0, y1, y2, y3, extrema); if (extrema[1] < extrema[0] && nExtrema > 1) { swapExtrema(); } y0_ = curve.cubicAt(y0, y1, y2, y3, extrema[0]); if (nExtrema > 1) { y1_ = curve.cubicAt(y0, y1, y2, y3, extrema[1]); } } if (nExtrema === 2) { // 分成三段单调函数 if (t < extrema[0]) { w += y0_ < y0 ? unit : -unit; } else if (t < extrema[1]) { w += y1_ < y0_ ? unit : -unit; } else { w += y3 < y1_ ? unit : -unit; } } else { // 分成两段单调函数 if (t < extrema[0]) { w += y0_ < y0 ? unit : -unit; } else { w += y3 < y0_ ? unit : -unit; } } } return w; } } function windingQuadratic(x0, y0, x1, y1, x2, y2, x, y) { // Quick reject if (y > y0 && y > y1 && y > y2 || y < y0 && y < y1 && y < y2) { return 0; } var nRoots = curve.quadraticRootAt(y0, y1, y2, y, roots); if (nRoots === 0) { return 0; } else { var t = curve.quadraticExtremum(y0, y1, y2); if (t >= 0 && t <= 1) { var w = 0; var y_ = curve.quadraticAt(y0, y1, y2, t); for (var i = 0; i < nRoots; i++) { // Remove one endpoint. var unit = roots[i] === 0 || roots[i] === 1 ? 0.5 : 1; var x_ = curve.quadraticAt(x0, x1, x2, roots[i]); if (x_ < x) { // Quick reject continue; } if (roots[i] < t) { w += y_ < y0 ? unit : -unit; } else { w += y2 < y_ ? unit : -unit; } } return w; } else { // Remove one endpoint. var unit = roots[0] === 0 || roots[0] === 1 ? 0.5 : 1; var x_ = curve.quadraticAt(x0, x1, x2, roots[0]); if (x_ < x) { // Quick reject return 0; } return y2 < y0 ? unit : -unit; } } } // TODO // Arc 旋转 function windingArc(cx, cy, r, startAngle, endAngle, anticlockwise, x, y) { y -= cy; if (y > r || y < -r) { return 0; } var tmp = Math.sqrt(r * r - y * y); roots[0] = -tmp; roots[1] = tmp; var diff = Math.abs(startAngle - endAngle); if (diff < 1e-4) { return 0; } if (diff % PI2 < 1e-4) { // Is a circle startAngle = 0; endAngle = PI2; var dir = anticlockwise ? 1 : -1; if (x >= roots[0] + cx && x <= roots[1] + cx) { return dir; } else { return 0; } } if (anticlockwise) { var tmp = startAngle; startAngle = normalizeRadian(endAngle); endAngle = normalizeRadian(tmp); } else { startAngle = normalizeRadian(startAngle); endAngle = normalizeRadian(endAngle); } if (startAngle > endAngle) { endAngle += PI2; } var w = 0; for (var i = 0; i < 2; i++) { var x_ = roots[i]; if (x_ + cx > x) { var angle = Math.atan2(y, x_); var dir = anticlockwise ? 1 : -1; if (angle < 0) { angle = PI2 + angle; } if (angle >= startAngle && angle <= endAngle || angle + PI2 >= startAngle && angle + PI2 <= endAngle) { if (angle > Math.PI / 2 && angle < Math.PI * 1.5) { dir = -dir; } w += dir; } } } return w; } function containPath(data, lineWidth, isStroke, x, y) { var w = 0; var xi = 0; var yi = 0; var x0 = 0; var y0 = 0; for (var i = 0; i < data.length;) { var cmd = data[i++]; // Begin a new subpath if (cmd === CMD.M && i > 1) { // Close previous subpath if (!isStroke) { w += windingLine(xi, yi, x0, y0, x, y); } // 如果被任何一个 subpath 包含 // if (w !== 0) { // return true; // } } if (i === 1) { // 如果第一个命令是 L, C, Q // 则 previous point 同绘制命令的第一个 point // // 第一个命令为 Arc 的情况下会在后面特殊处理 xi = data[i]; yi = data[i + 1]; x0 = xi; y0 = yi; } switch (cmd) { case CMD.M: // moveTo 命令重新创建一个新的 subpath, 并且更新新的起点 // 在 closePath 的时候使用 x0 = data[i++]; y0 = data[i++]; xi = x0; yi = y0; break; case CMD.L: if (isStroke) { if (line.containStroke(xi, yi, data[i], data[i + 1], lineWidth, x, y)) { return true; } } else { // NOTE 在第一个命令为 L, C, Q 的时候会计算出 NaN w += windingLine(xi, yi, data[i], data[i + 1], x, y) || 0; } xi = data[i++]; yi = data[i++]; break; case CMD.C: if (isStroke) { if (cubic.containStroke(xi, yi, data[i++], data[i++], data[i++], data[i++], data[i], data[i + 1], lineWidth, x, y)) { return true; } } else { w += windingCubic(xi, yi, data[i++], data[i++], data[i++], data[i++], data[i], data[i + 1], x, y) || 0; } xi = data[i++]; yi = data[i++]; break; case CMD.Q: if (isStroke) { if (quadratic.containStroke(xi, yi, data[i++], data[i++], data[i], data[i + 1], lineWidth, x, y)) { return true; } } else { w += windingQuadratic(xi, yi, data[i++], data[i++], data[i], data[i + 1], x, y) || 0; } xi = data[i++]; yi = data[i++]; break; case CMD.A: // TODO Arc 判断的开销比较大 var cx = data[i++]; var cy = data[i++]; var rx = data[i++]; var ry = data[i++]; var theta = data[i++]; var dTheta = data[i++]; // TODO Arc 旋转 i += 1; var anticlockwise = 1 - data[i++]; var x1 = Math.cos(theta) * rx + cx; var y1 = Math.sin(theta) * ry + cy; // 不是直接使用 arc 命令 if (i > 1) { w += windingLine(xi, yi, x1, y1, x, y); } else { // 第一个命令起点还未定义 x0 = x1; y0 = y1; } // zr 使用scale来模拟椭圆, 这里也对x做一定的缩放 var _x = (x - cx) * ry / rx + cx; if (isStroke) { if (arc.containStroke(cx, cy, ry, theta, theta + dTheta, anticlockwise, lineWidth, _x, y)) { return true; } } else { w += windingArc(cx, cy, ry, theta, theta + dTheta, anticlockwise, _x, y); } xi = Math.cos(theta + dTheta) * rx + cx; yi = Math.sin(theta + dTheta) * ry + cy; break; case CMD.R: x0 = xi = data[i++]; y0 = yi = data[i++]; var width = data[i++]; var height = data[i++]; var x1 = x0 + width; var y1 = y0 + height; if (isStroke) { if (line.containStroke(x0, y0, x1, y0, lineWidth, x, y) || line.containStroke(x1, y0, x1, y1, lineWidth, x, y) || line.containStroke(x1, y1, x0, y1, lineWidth, x, y) || line.containStroke(x0, y1, x0, y0, lineWidth, x, y)) { return true; } } else { // FIXME Clockwise ? w += windingLine(x1, y0, x1, y1, x, y); w += windingLine(x0, y1, x0, y0, x, y); } break; case CMD.Z: if (isStroke) { if (line.containStroke(xi, yi, x0, y0, lineWidth, x, y)) { return true; } } else { // Close a subpath w += windingLine(xi, yi, x0, y0, x, y); // 如果被任何一个 subpath 包含 // FIXME subpaths may overlap // if (w !== 0) { // return true; // } } xi = x0; yi = y0; break; } } if (!isStroke && !isAroundEqual(yi, y0)) { w += windingLine(xi, yi, x0, y0, x, y) || 0; } return w !== 0; } function contain(pathData, x, y) { return containPath(pathData, 0, false, x, y); } function containStroke(pathData, lineWidth, x, y) { return containPath(pathData, lineWidth, true, x, y); } exports.contain = contain; exports.containStroke = containStroke;