Reactjs 剪切路径动态变换以填充容器
我正在制作一个react组件,我希望能够传递任何图像及其尺寸,一个根据矩形区域的x、y宽度和高度计算的剪辑路径。这部分我做得很好。然后我想缩放这个裁剪区域以填充一个div,现在我有这个div,只是原始图像的尺寸以保持简单。我的缩放部分计算正确,但无法计算出数学来平移缩放的剪辑路径区域。以下是我在Typescript中的组件:Reactjs 剪切路径动态变换以填充容器,reactjs,math,scale,translate,clip-path,Reactjs,Math,Scale,Translate,Clip Path,我正在制作一个react组件,我希望能够传递任何图像及其尺寸,一个根据矩形区域的x、y宽度和高度计算的剪辑路径。这部分我做得很好。然后我想缩放这个裁剪区域以填充一个div,现在我有这个div,只是原始图像的尺寸以保持简单。我的缩放部分计算正确,但无法计算出数学来平移缩放的剪辑路径区域。以下是我在Typescript中的组件: interface RootProps { links: Link[]; } interface RootState { } class Root extend
interface RootProps {
links: Link[];
}
interface RootState {
}
class Root extends React.Component<RootProps, RootState> {
constructor(props) {
super(props);
this.state = {
}
}
pp = (x: number, y: number): string => {
return x + "% " + y + "%"
}
renderClippedImage = (name: string, x: number, y: number, width: number, height: number) => {
let iWidth = 600;
let iHeight = 360;
let p1 = {
x: (x / iWidth) * 100,
y: (y / iHeight) * 100
}
let p2 = {
x: (x / iWidth) * 100,
y: ((y + height) / iHeight) * 100
}
let p3 = {
x: ((x + width) / iWidth) * 100,
y: ((y + height) / iHeight) * 100
}
let p4 = {
x: ((x + width) / iWidth) * 100,
y: (y / iHeight) * 100
}
let clipPathString = 'polygon(' +
this.pp(p1.x, p1.y) + ', ' +
this.pp(p2.x, p2.y) + ', ' +
this.pp(p3.x, p3.y) + ', ' +
this.pp(p4.x, p4.y) + ')';
let pX = (x) / iWidth;
let pY = (y) / iHeight;
let portionCoverageX = (width) / iWidth;
let portionCoverageY = (height) / iHeight;
let scaleX = 1;
let scaleY = 1;
if (portionCoverageX > 0) {
scaleX = 1 / portionCoverageX;
}
if (portionCoverageY > 0) {
scaleY = 1 / portionCoverageY;
}
let translateX = -(((pX * scaleX) / 2) * 100); //this doesn't work
let translateY = 0; //similar issues getting this to work
let pathClipping = {
WebkitClipPath: clipPathString,
clipPath: clipPathString,
transform: 'translateX(' + translateX + '%) translateY(' + translateY + '%) scaleX(' + scaleX + ') scaleY(' + scaleY + ')'
}
console.log({
name: name,
pX: pX,
pY: pY,
portionCoverageX: portionCoverageX,
portionCoverageY: portionCoverageY,
scaleX: scaleX,
scaleY: scaleY,
translateX: translateX,
translateY: translateY
})
return (
<div style={{ textAlign: 'center', width: '100%', backgroundColor: 'lightseagreen' }}>
<b>{name}</b><br />
<div style={{ display: 'inline-block', width: 640, height: 360, backgroundColor: 'darkslateblue' }}>
<img width="640" height="360" src="https://placekitten.com/640/360" style={pathClipping} />
</div>
</div>
)
}
render() {
return (
<div style={{textAlign: 'center'}}>
<b>Original</b><br />
<img width="640" height="360" src="https://placekitten.com/640/360" />
<br />
{this.renderClippedImage("one", 80, 100, 200, 100)}
<br />
{this.renderClippedImage("two", 50, 50, 150, 100)}
<br />
{this.renderClippedImage("three", 300, 10, 300, 340)}
</div>
)
}
}
ReactDOM.render(<Root />, document.getElementById('mount-node'));
translateY也是一个类似的问题,任何帮助都将不胜感激。我认为您可以将“变换原点”设置为左上角,这样您就可以对变换位置和比例进行更简单的计算
let scaleX = iWidth / width;
let scaleY = iHeight / height;
let pX = x / iWidth;
let pY = y / iHeight;
let translateX = -pX * 100 * scaleX;
let translateY = -pY * 100 * scaleY;
let pathClipping = {
WebkitClipPath: clipPathString,
clipPath: clipPathString,
transformOrigin: `top left`,
transform: `
translate(${translateX}%, ${translateY}%)
scale(${scaleX}, ${scaleY})
`
};
看这里就是这样!我看到你在代码末尾的另一个运行/示例中故意用无效维度打破了它,很好,我计划用其他方式处理。是的,这解决了我的问题,有趣的transformOrigin属性,我甚至没有尝试将其混入,但这是有意义的。啊,那么如果覆盖率x>0是你的支票,对吗?我忘了把它放回去。你也许可以做一些数学运算,使其适用于默认的变换原点和中心,但如果这不是一个要求,将其设置为左上角会简单得多。实际上,我认为我从未处理过范围或范围,例如比源图像值更宽的区域,但这应该很容易添加。正如你提到的左上角,你修改的数学为我解决了这个问题,谢谢。
let scaleX = iWidth / width;
let scaleY = iHeight / height;
let pX = x / iWidth;
let pY = y / iHeight;
let translateX = -pX * 100 * scaleX;
let translateY = -pY * 100 * scaleY;
let pathClipping = {
WebkitClipPath: clipPathString,
clipPath: clipPathString,
transformOrigin: `top left`,
transform: `
translate(${translateX}%, ${translateY}%)
scale(${scaleX}, ${scaleY})
`
};