@turbox3d/shared/lib/graphic.js

turbox shared internal utility

"use strict";

var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");
Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.getRelativePositionFromEvent = getRelativePositionFromEvent;
exports.pointInRect = pointInRect;
var _slicedToArray2 = _interopRequireDefault(require("@babel/runtime/helpers/slicedToArray"));
/** 判断点是否在矩形内 */
function pointInRect(p, rect) {
  var _rect = (0, _slicedToArray2["default"])(rect, 2),
    r1 = _rect[0],
    r2 = _rect[1];
  var c1 = (p.x - r1.x) * (p.x - r2.x);
  var c2 = (p.y - r1.y) * (p.y - r2.y);
  return c1 <= 0 && c2 <= 0;
}
/**
 * 获得点击位置相对于 canvas 的坐标
 * 如果输入参数不合法，或点击位置超出 canvas 的 clientRect 则返回 undefined
 * @param vec 事件坐标
 * @param canvas 要接受的 canvas 对象
 */
function getRelativePositionFromEvent(vec, rect) {
  var point = {
    x: vec.x - rect.x,
    y: vec.y - rect.y
  };
  if (point.x <= 0 || point.y <= 0 || point.x > rect.width || point.y > rect.height) {
    return undefined;
  }
  return point;
}