three.js: Undefinend values in planeBufferGeometry causes raycaster to return empty

Description of the problem

I create a planeBufferGeometry and fill it like so:

var positions = new Float32Array(grid.elevations.length * 3).fill(undefined);
for(stuff){
 positions[i * 3 + 0] = xpos ;
 positions[i * 3 + 1] = ypos;
 positions[i * 3 + 2] = (isNaN(zpos)) ? undefined : zpos;
}

var geometry = new THREE.PlaneBufferGeometry();
geometry.addAttribute('position', new THREE.BufferAttribute(positions, 3));
var terrainMesh = new THREE.Mesh(geometry, material);
terrainMesh.name = myMesh;
scene.add(terrainMesh)

then raycast using:

raycaster.setFromCamera(mouse, camera);
var intersects = raycaster.intersectObject(scene.getObjectByName('myMesh'));

intersects is always empty. If I do this: vertices[i * 3 + 2] = (isNaN(zpos)) ? -1: zpos;

I get a result;

Currently I’m thinking best work around is making a second planeBufferGeometry and assign the undefined values a -1. Then handle if(z = -1) . This position array can get rather large though and having another one is not ideal.

Three.js version

• Dev
• [ X] r84
• …

Browser

• All of them
• Chrome
• Firefox
• Internet Explorer

OS

• All of them
• Windows
• macOS
• Linux
• Android
• iOS

Hardware Requirements (graphics card, VR Device, …)