我需要用多边形的角坐标画一个虚线多边形。为此,我将在拐角上迭代,并在所有迭代中在两个角(角点和corneri+1)之间绘制虚线。我在网络上找到了一些代码,因此我目前正在这样做:
offSetCorners.forEach((point, i) => {
let endPoint = i < offSetCorners.length - 1 ? offSetCorners[i + 1] : offSetCorners[0];
zoneGraphic.drawDash(point.x, point.y, endPoint.x, endPoint.y);
});
drawDash(x1: number, y1: number, x2: number, y2: number, dashLength = 5, spaceLength = 5) {
let x = x2 - x1;
let y = y2 - y1;
let hyp = Math.sqrt(x * x + y * y);
let units = hyp / (dashLength + spaceLength);
let dashSpaceRatio = dashLength / (dashLength + spaceLength);
let dashX = (x / units) * dashSpaceRatio;
let spaceX = x / units - dashX;
let dashY = (y / units) * dashSpaceRatio;
let spaceY = y / units - dashY;
zoneGraphic.moveTo(x1, y1);
while (hyp > 0) {
x1 += dashX;
y1 += dashY;
hyp -= dashLength;
if (hyp < 0) {
x1 = x2;
y1 = y2;
}
zoneGraphic.lineTo(x1, y1);
x1 += spaceX;
y1 += spaceY;
zoneGraphic.moveTo(x1, y1);
hyp -= spaceLength;
}
zoneGraphic.moveTo(x2, y2);
}但是这画了像这样的虚线

我想要的是

发布于 2022-08-10 11:11:38
您可以使用setLineDash实现这一点:
https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/setLineDash
下面是一个代码示例:
var ctx = document.getElementById("c").getContext("2d");
ctx.font = "60px Arial";
ctx.setLineDash([5, 5]);
ctx.strokeText("ABC", 50, 60);
ctx.rect(5, 5, 190, 90);
ctx.lineTo(40,80);
ctx.stroke();<canvas id="c" width=200 height=100></canvas>
那只是纯粹的JS,不涉及Pixi,我想在那个库中也可以使用,如果不是,您应该可以直接在画布上使用JS来完成它。
发布于 2022-08-11 12:06:10
https://stackoverflow.com/questions/73305152
复制相似问题