Backup camera graphics without ParkAssist? Cross traffic alert?

Is there a hack to add interactive graphics (shown below) to the backup camera if [1] you don't have Intelligent Parking Assist, or [2] you don't want to install an aftermarket kit that changes your dash interface? What's the least invasive way to add this feature?

Is there a mod to add cross traffic alert? I realize it would mean adding sensors.

Is Entune hackable? Could additional program features be added through the USB?

 

Member Cproaudio had some interesting ideas in the "How about blind spot moniter" thread.

Why aren't aftermarket kits available for cross traffic alert if they exist for blind spot monitoring? Parts seem simple enough: sensors, indicator light, alarm beeper, and control box.

Must be a combination of proprietary technology and coding for signal processing on controller's logic board.