@logicflow/core
Version:
LogicFlow, help you quickly create flowcharts
73 lines (72 loc) • 3.01 kB
JavaScript
// 各类算法的实现
export * from './outline';
export * from './edge';
/*
* 计算垂直边的与起始点有一定距离对称，边垂直于边的点
* 调用方：计算箭头位置，计算扩大变得点击区域
*/
export var getVerticalPointOfLine = function (config) {
/*
** offset: 端点到垂直点的距离
** verticalLength: 两边点到垂直点的距离
** type: 标识求的是线段的开始端点/结束端点
*/
var start = config.start, end = config.end, offset = config.offset, verticalLength = config.verticalLength, type = config.type;
var pointPosition = {
leftX: 0,
leftY: 0,
rightX: 0,
rightY: 0,
};
// // 边与水平线的夹角
var angleOfHorizontal = Math.atan((end.y - start.y) / (end.x - start.x));
// 边和两边点的夹角
var angleOfPoints = Math.atan(offset / verticalLength);
// 点到起点的距离
var len = Math.sqrt(verticalLength * verticalLength + offset * offset);
if (type === 'start') {
if (end.x >= start.x) {
pointPosition.leftX =
start.x + len * Math.sin(angleOfHorizontal + angleOfPoints);
pointPosition.leftY =
start.y - len * Math.cos(angleOfHorizontal + angleOfPoints);
pointPosition.rightX =
start.x - len * Math.sin(angleOfHorizontal - angleOfPoints);
pointPosition.rightY =
start.y + len * Math.cos(angleOfHorizontal - angleOfPoints);
}
else {
pointPosition.leftX =
start.x - len * Math.sin(angleOfHorizontal + angleOfPoints);
pointPosition.leftY =
start.y + len * Math.cos(angleOfHorizontal + angleOfPoints);
pointPosition.rightX =
start.x + len * Math.sin(angleOfHorizontal - angleOfPoints);
pointPosition.rightY =
start.y - len * Math.cos(angleOfHorizontal - angleOfPoints);
}
}
else if (type === 'end') {
if (end.x >= start.x) {
pointPosition.leftX =
end.x + len * Math.sin(angleOfHorizontal - angleOfPoints);
pointPosition.leftY =
end.y - len * Math.cos(angleOfHorizontal - angleOfPoints);
pointPosition.rightX =
end.x - len * Math.sin(angleOfHorizontal + angleOfPoints);
pointPosition.rightY =
end.y + len * Math.cos(angleOfHorizontal + angleOfPoints);
}
else {
pointPosition.leftX =
end.x - len * Math.sin(angleOfHorizontal - angleOfPoints);
pointPosition.leftY =
end.y + len * Math.cos(angleOfHorizontal - angleOfPoints);
pointPosition.rightX =
end.x + len * Math.sin(angleOfHorizontal + angleOfPoints);
pointPosition.rightY =
end.y - len * Math.cos(angleOfHorizontal + angleOfPoints);
}
}
return pointPosition;
};