You can use a polygon and hide the edges and vertices of the polygon. Here is an example:
var board = JXG.JSXGraph.initBoard("jxgbox", {
boundingbox: [-1, 5, 5, -1],
axis: true
});
var p1 = board.create('point', [2, 1]);
var shade = board.create('polygon', [p1, [0,p1.Y()], [0,4]],
{
borders: {visible: false},
vertices: {visible: false}
}
);
If you need to intersect the coordinate axes, you can access them with
board.defaultAxes.x
and board.defaultAxes.y
.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…