Audi’s e-tron electric SUV will replace side mirrors with cameras when it arrives locally next year, joined by the likes of McLaren’s Speedtail supercar and even Mercedes-Benz Actross trucks.

On reflection, it was bound to happen.

High-resolution digital cameras, crisp LCD or OLED displays and lag-free computers laid the groundwork to remove a simple feature found on road cars for almost a century.

Audi and McLaren removed external mirrors from their next-gen models to reduce wind resistance.

In the Audi’s case, the aim is to eke the maximum possible driving range from its battery and electric motors, contributing about 2.5 kilometres to its 436 kilometre range (measured using the WLTP standard).

We tested the e-tron overseas in 2018 and found that the digital mirrors had the speed and quality to match conventional glass, but that it takes time to get used to lower placement for the displays, and that our eyes needed a moment longer to focus on the closer image.

It uses HDR technology found in modern televisions to reduce glare to provide a more detailed image in gloomy conditions.

While Honda and Lexus offer similar technology overseas, Audi should be the first to offer it in Australia.

The new Mclaren Speedtail’s reliance on cameras is about keeping drag to a minimum so that the car can reach its 403km/h (a neat 250mph) top speed without fuss. McLaren signed off the car’s technology by accelerating beyond 400km/h dozens of times at the Kennedy Space Centre in Florida, where test driver Kenny Brack pushed the 772kW machine to its limit.

You could argue that rear-view mirrors are unnecessary at that speed, unless the driver is being pursued by a Bugatti Chiron. Or F-35 strike fighter.

But the McLaren is designed to be used on the road on a semi-regular basis, so it needs to meet practical requirements. And the brand’s 2020 solution is much more elegant than that of the original McLaren F1, which borrowed mass-produced mirrors from a humble Volkswagen coupe.

As for Mercedes’ latest trucks, the brand says the change will contribute to improved efficiency and safety.

Roof-mounted cameras linked to digital displays on the windscreen frame free up the driver’s forward and directional vision, while being less susceptible to dirt and grime.

The system has a special mode for reversing and uses AI to detect whether there may be a problem with the trailers — it will alert the driver if the length of a vehicle changes.

Drivers sleeping in the cab overnight can access camera feeds remotely to check whether potential thieves are interfering with its cargo. Testers say the technology contributes to a noticeable reduction in fuel consumption.

The new Actross trucks with MirrorCam go on sale in 2020.