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title: useIntersect sourcecode: src/core/useIntersect.tsx

<Grid cols={4}> <li> <Codesandbox id="gsm1y" /> </li> </Grid>

A very cheap frustum check that gives you a reference you can observe in order to know if the object has entered the view or is outside of it. This relies on THREE.Object3D.onBeforeRender so it only works on objects that are effectively rendered, like meshes, lines, sprites. It won't work on groups, object3d's, bones, etc.

const ref = useIntersect((visible) => console.log('object is visible', visible))
return <mesh ref={ref} />