Viewport

This component handles camera zooming to window size and zooming in zoomable steps. The binding of [+] and [-] keys relies on the Keyboard component.

`property` viewPort.width : `false`

Let camera zoom to contain at least width.

`property` viewPort.height : `false`

Let camera zoom to contain at least height.

`property` viewPort.maxScale

Maximum zoom factor of camera.

`property` viewPort.minScale

Minimum zoom factor of camera.