javascript - Rotate camera in Three.js with mouse

Question

I have quite a few objects in my scene so rotating all of them could be a pain. So what is the most easy way to move camera around origin on mouse click and drag? This way all the lights, objects in the scene are in the same location, so the only thing changing is the camera. Three.js does not provide a way to rotate a camera around a point, or does it?

Thank you

Answer 1

Here's a project with a rotating camera. Looking through the source it seems to just move the camera position in a circle.

function onDocumentMouseMove( event ) {

    event.preventDefault();

    if ( isMouseDown ) {

        theta = - ( ( event.clientX - onMouseDownPosition.x ) * 0.5 )
                + onMouseDownTheta;
        phi = ( ( event.clientY - onMouseDownPosition.y ) * 0.5 )
              + onMouseDownPhi;

        phi = Math.min( 180, Math.max( 0, phi ) );

        camera.position.x = radious * Math.sin( theta * Math.PI / 360 )
                            * Math.cos( phi * Math.PI / 360 );
        camera.position.y = radious * Math.sin( phi * Math.PI / 360 );
        camera.position.z = radious * Math.cos( theta * Math.PI / 360 )
                            * Math.cos( phi * Math.PI / 360 );
        camera.updateMatrix();

    }

    mouse3D = projector.unprojectVector(
        new THREE.Vector3(
            ( event.clientX / renderer.domElement.width ) * 2 - 1,
            - ( event.clientY / renderer.domElement.height ) * 2 + 1,
            0.5
        ),
        camera
    );
    ray.direction = mouse3D.subSelf( camera.position ).normalize();

    interact();
    render();

}

Here's another demo and in this one I think it just creates a new THREE.TrackballControls object with the camera as a parameter, which is probably the better way to go.

controls = new THREE.TrackballControls( camera );
controls.target.set( 0, 0, 0 )