Fabric.js is a powerful and simple Javascript HTML5 canvas library
Fabric.js demos · Custom controls, polygon
Custom controls, polygon 예제에서 Polygon으로 변환된 개체의 절대좌표를 계산한다.
//
//
//canvas = new fabric.Canvas("canvas");
//convertAbsolutePoint(canvas.getActiveObject());
function convertAbsolutePoint(area) {
return area.points
.map(p=>fabric.util.transformPoint({ x:p.x - area.pathOffset.x, y:p.y - area.pathOffset.y }, area.calcTransformMatrix()));
}