cione-comp-lib
Version:
`$ yarn add cione-comp-lib` 或者 `$ npm i cione-comp-lib -S`
196 lines (195 loc) • 6.06 kB
JavaScript
import { cubicSubdivide } from "../core/curve.mjs";
import PathProxy from "../core/PathProxy.mjs";
var CMD = PathProxy.CMD;
function aroundEqual(a, b) {
return Math.abs(a - b) < 1e-5;
}
function pathToBezierCurves(path) {
var data = path.data;
var len = path.len();
var bezierArrayGroups = [];
var currentSubpath;
var xi = 0;
var yi = 0;
var x0 = 0;
var y0 = 0;
function createNewSubpath(x, y) {
if (currentSubpath && currentSubpath.length > 2) {
bezierArrayGroups.push(currentSubpath);
}
currentSubpath = [x, y];
}
function addLine(x02, y02, x12, y12) {
if (!(aroundEqual(x02, x12) && aroundEqual(y02, y12))) {
currentSubpath.push(x02, y02, x12, y12, x12, y12);
}
}
function addArc(startAngle2, endAngle2, cx2, cy2, rx2, ry2) {
var delta = Math.abs(endAngle2 - startAngle2);
var len2 = Math.tan(delta / 4) * 4 / 3;
var dir = endAngle2 < startAngle2 ? -1 : 1;
var c1 = Math.cos(startAngle2);
var s1 = Math.sin(startAngle2);
var c2 = Math.cos(endAngle2);
var s2 = Math.sin(endAngle2);
var x12 = c1 * rx2 + cx2;
var y12 = s1 * ry2 + cy2;
var x4 = c2 * rx2 + cx2;
var y4 = s2 * ry2 + cy2;
var hx = rx2 * len2 * dir;
var hy = ry2 * len2 * dir;
currentSubpath.push(x12 - hx * s1, y12 + hy * c1, x4 + hx * s2, y4 - hy * c2, x4, y4);
}
var x1;
var y1;
var x2;
var y2;
for (var i = 0; i < len; ) {
var cmd = data[i++];
var isFirst = i === 1;
if (isFirst) {
xi = data[i];
yi = data[i + 1];
x0 = xi;
y0 = yi;
if (cmd === CMD.L || cmd === CMD.C || cmd === CMD.Q) {
currentSubpath = [x0, y0];
}
}
switch (cmd) {
case CMD.M:
xi = x0 = data[i++];
yi = y0 = data[i++];
createNewSubpath(x0, y0);
break;
case CMD.L:
x1 = data[i++];
y1 = data[i++];
addLine(xi, yi, x1, y1);
xi = x1;
yi = y1;
break;
case CMD.C:
currentSubpath.push(data[i++], data[i++], data[i++], data[i++], xi = data[i++], yi = data[i++]);
break;
case CMD.Q:
x1 = data[i++];
y1 = data[i++];
x2 = data[i++];
y2 = data[i++];
currentSubpath.push(xi + 2 / 3 * (x1 - xi), yi + 2 / 3 * (y1 - yi), x2 + 2 / 3 * (x1 - x2), y2 + 2 / 3 * (y1 - y2), x2, y2);
xi = x2;
yi = y2;
break;
case CMD.A:
var cx = data[i++];
var cy = data[i++];
var rx = data[i++];
var ry = data[i++];
var startAngle = data[i++];
var endAngle = data[i++] + startAngle;
i += 1;
var anticlockwise = !data[i++];
x1 = Math.cos(startAngle) * rx + cx;
y1 = Math.sin(startAngle) * ry + cy;
if (isFirst) {
x0 = x1;
y0 = y1;
createNewSubpath(x0, y0);
} else {
addLine(xi, yi, x1, y1);
}
xi = Math.cos(endAngle) * rx + cx;
yi = Math.sin(endAngle) * ry + cy;
var step = (anticlockwise ? -1 : 1) * Math.PI / 2;
for (var angle = startAngle; anticlockwise ? angle > endAngle : angle < endAngle; angle += step) {
var nextAngle = anticlockwise ? Math.max(angle + step, endAngle) : Math.min(angle + step, endAngle);
addArc(angle, nextAngle, cx, cy, rx, ry);
}
break;
case CMD.R:
x0 = xi = data[i++];
y0 = yi = data[i++];
x1 = x0 + data[i++];
y1 = y0 + data[i++];
createNewSubpath(x1, y0);
addLine(x1, y0, x1, y1);
addLine(x1, y1, x0, y1);
addLine(x0, y1, x0, y0);
addLine(x0, y0, x1, y0);
break;
case CMD.Z:
currentSubpath && addLine(xi, yi, x0, y0);
xi = x0;
yi = y0;
break;
}
}
if (currentSubpath && currentSubpath.length > 2) {
bezierArrayGroups.push(currentSubpath);
}
return bezierArrayGroups;
}
function adpativeBezier(x0, y0, x1, y1, x2, y2, x3, y3, out, scale) {
if (aroundEqual(x0, x1) && aroundEqual(y0, y1) && aroundEqual(x2, x3) && aroundEqual(y2, y3)) {
out.push(x3, y3);
return;
}
var PIXEL_DISTANCE = 2 / scale;
var PIXEL_DISTANCE_SQR = PIXEL_DISTANCE * PIXEL_DISTANCE;
var dx = x3 - x0;
var dy = y3 - y0;
var d = Math.sqrt(dx * dx + dy * dy);
dx /= d;
dy /= d;
var dx1 = x1 - x0;
var dy1 = y1 - y0;
var dx2 = x2 - x3;
var dy2 = y2 - y3;
var cp1LenSqr = dx1 * dx1 + dy1 * dy1;
var cp2LenSqr = dx2 * dx2 + dy2 * dy2;
if (cp1LenSqr < PIXEL_DISTANCE_SQR && cp2LenSqr < PIXEL_DISTANCE_SQR) {
out.push(x3, y3);
return;
}
var projLen1 = dx * dx1 + dy * dy1;
var projLen2 = -dx * dx2 - dy * dy2;
var d1Sqr = cp1LenSqr - projLen1 * projLen1;
var d2Sqr = cp2LenSqr - projLen2 * projLen2;
if (d1Sqr < PIXEL_DISTANCE_SQR && projLen1 >= 0 && d2Sqr < PIXEL_DISTANCE_SQR && projLen2 >= 0) {
out.push(x3, y3);
return;
}
var tmpSegX = [];
var tmpSegY = [];
cubicSubdivide(x0, x1, x2, x3, 0.5, tmpSegX);
cubicSubdivide(y0, y1, y2, y3, 0.5, tmpSegY);
adpativeBezier(tmpSegX[0], tmpSegY[0], tmpSegX[1], tmpSegY[1], tmpSegX[2], tmpSegY[2], tmpSegX[3], tmpSegY[3], out, scale);
adpativeBezier(tmpSegX[4], tmpSegY[4], tmpSegX[5], tmpSegY[5], tmpSegX[6], tmpSegY[6], tmpSegX[7], tmpSegY[7], out, scale);
}
function pathToPolygons(path, scale) {
var bezierArrayGroups = pathToBezierCurves(path);
var polygons = [];
scale = scale || 1;
for (var i = 0; i < bezierArrayGroups.length; i++) {
var beziers = bezierArrayGroups[i];
var polygon = [];
var x0 = beziers[0];
var y0 = beziers[1];
polygon.push(x0, y0);
for (var k = 2; k < beziers.length; ) {
var x1 = beziers[k++];
var y1 = beziers[k++];
var x2 = beziers[k++];
var y2 = beziers[k++];
var x3 = beziers[k++];
var y3 = beziers[k++];
adpativeBezier(x0, y0, x1, y1, x2, y2, x3, y3, polygon, scale);
x0 = x3;
y0 = y3;
}
polygons.push(polygon);
}
return polygons;
}
export { pathToBezierCurves, pathToPolygons };