Correctly zoom camera in and out of layer texture

Currently trying to scale a layer’s texture in and out with the camera but don’t know the correct math to do so. See https://playground.babylonjs.com/#K9MWF6#58

//zoom
scene.activeCamera.onProjectionMatrixChangedObservable.add(function() {
    const newWidth = camera.orthoRight - camera.orthoLeft;
    const widthScale = newWidth / width;
    layer.scale.x = widthScale;

    const newHeight = camera.orthoTop - camera.orthoBottom;
    const heightScale = newHeight / height;

    layer.scale.y = heightScale;

    // what is the correct way to scale the layer's texture?
    layer.texture.uScale = 1/ widthScale;
    layer.texture.vScale = 1/ heightScale;
});

This might help you!

Added to your PG: https://playground.babylonjs.com/#K9MWF6#59