CODEWITHSUNDEEP
three.js
Anna
Anna

Reputation: 2855

How to find the coordinates of the viewfield corners of my Three.js camera?

My Three.js app has a static perspective camera looking on (0,0,0). How can I find the x/y coordinates in the y=0 plane of the corners of the camera's viewfield? The app covers the entire web browser, so this would correspond to the corners of the web browser. I want to render 3D models between those corners.

Upvotes: 0

Views: 113

Answers (1)

Mugen87
Mugen87

Reputation: 31086

I want to render 3D models between those corners.

Just having the mentioned corner points is not sufficient to determine whether the user can see an object or not. The camera also has a near/far plane and also a perspective which you should take into account.

I suggest you use a different workflow and create an instance of THREE.Frustum based on the camera's projection screen matrix. The code looks like so:

const frustum = new THREE.Frustum();
const projScreenMatrix = new THREE.Matrix4();

projScreenMatrix.multiplyMatrices( camera.projectionMatrix, camera.matrixWorldInverse );
frustum.setFromProjectionMatrix( _projScreenMatrix );

You can then use methods like Frustum.intersectsObject() or Frustum.intersectsSprite() to determine whether 3D objects are in the view frustum or not.

This is actually the way WebGLRenderer performs view frustum culling.

Upvotes: 1

Related Questions