modify(clip, type) {
var [clipPositionX, clipPositionY] = [clip.positionX - clip.positionX % 25, clip.positionY - clip.positionY % 25];
var absoluteClipPoints = clip.points.map(([x, y]) => {
return {X: x + clipPositionX - clip.options.center[0], Y: y + clipPositionY - clip.options.center[1]};
});
var absolutePoints = this.points.map(([x, y]) => {
return {X: x + this.positionX, Y: y + this.positionY};
});
var clipper = new ClipperLib.Clipper();
clipper.AddPaths([absolutePoints], ClipperLib.PolyType.ptSubject, true);
clipper.AddPaths([absoluteClipPoints], ClipperLib.PolyType.ptClip, true);
var cliptype;
switch (type) {
case 'subtract':
cliptype = ClipperLib.ClipType.ctDifference;
break;
case 'add':
cliptype = ClipperLib.ClipType.ctUnion;
break;
}
var polyfilltype = ClipperLib.PolyFillType.pftPositive;
var result = new ClipperLib.Paths();
clipper.Execute(cliptype, result);
var processedResult = result[0].map((point) => {
return [point.X - this.positionX, point.Y - this.positionY];
});
this.points = processedResult;
this.render();
}
function computeWalkableArea(object) {
var cpr = new ClipperLib.Clipper();
var coords = object.geometry.coordinates;
var perimeter = coords[0];
var subj_paths = [fromJsonToClipper(perimeter)];
var clip_paths = [];
for (var i = 1; i < coords.length; i++) {
var internal_hole = coords[i];
clip_paths.push(fromJsonToClipper(internal_hole));
}
for (k in object.children) {
var child = object.children[k];
if (child.geometry.type === 'Polygon') {
clip_paths.push(fromJsonToClipper(child.getLocalCoordinates()));
}
}
// console.log(subj_paths);
//console.log(clip_paths);
cpr.AddPaths(subj_paths, ClipperLib.PolyType.ptSubject, true); // true means closed path
cpr.AddPaths(clip_paths, ClipperLib.PolyType.ptClip, true);
var walkableArea = new ClipperLib.Paths();
var succeeded = cpr.Execute(ClipperLib.ClipType.ctDifference, walkableArea,
ClipperLib.PolyFillType.pftNonZero, ClipperLib.PolyFillType.pftNonZero);
walkableArea = walkableArea.map(fromClipperToJson);
return walkableArea;
}