@sebavan, is there another alternative solution to get crisp GUI, without setting engine hardware scaling level?
I see similar issue three years ago, still not resolved.
Correcting: this example had reversed label, setting engine.setHardwareScalingLevel < 1 did result in crispier 3D content. But current work around requires setHardwareScalingLevel < 1, and manually setting all GUI controls with scaleX = window.devicePixelRatio.
Right now, it’s impossible to achieve crisp GUI on retina screens without suffering performance for 3D content.