Rendered for real

It's a hit-and-miss affair, attempting to portray how a car will look ahead of its debut in production form.

Obviously the good people who create computer-generated images ('com-gens') do their level best with what's known from car company execs with loose lips.

Automedia is the European-based company that supplies motoring.com.au with com-gens (and spy pics), and their efforts – frequently based on scant information – can be very close to the mark.

But the artists don't always get it right, with the benefit of hindsight.

We've assembled some com-gens from the past, to run alongside the finished product. See what you think… which images were on the money, and which were so far astray…?

Let's start with the Volvo S90. The com-gen for Volvo's new flagship was produced something like three years before the production S90 saw the light of day. You'd have to say it's a valiant attempt, and the proportions look roughly right. But what about that nose? It's all very angular and bluff, possibly as a consequence of the artist focusing on pedestrian safety, which was a big issue in 2013. To our eyes, the S90 com-gen looks more like Ford's Interceptor concept from 2007. We rate it a C (and an A for effort).

How about the Toyota Corolla hatch? From the A pillars back the com-gen of the European-market Toyota Auris basically nailed it. But as with the S90, the front end doesn't look right at all. Unlike the S90, which was a very long-range projection, the Auris com-gen was created just two months ahead of the launch of the Corolla hatch in Australia.

Before getting stuck into the artist concerned, however, it should be noted that the com-gen is much closer to the appearance of the production Auris in other markets. There is a markedly different nose for the Corolla hatch in markets where it's badged 'Auris'. If you were to put a score on the artist's work in this instance, you'd say it's worth a B+.

A com-gen from 2014 shows just how much guesswork went into the artist's depiction of the Opel Astra. We reckon the information to hand was off the beam when the artist set to work on the Astra com-gen. The headlight clusters don't flow into the grille – as they do in the production version of the car – and the sculpture lines are all wrong, both in the bonnet and the front doors. We've got to be frank here, the subject of the com-gen looks a more attractive car than the production model. It's worth extra credit for that, but still rates just B-.

Back in 2012, little was known about the car that came to be badged as the Maserati Ghibli. This com-gen takes a fair crack at reproducing how the Ghibli would look – at a time when the vehicle was still addressed in some parts as the Quattroporticina. The headlights in the com-gen are well adrift from reality, the production car's raised boot lid – in the Chris Bangle style – is missing from the com-gen, and the production car is a little squarer and higher around the rear roofline. Overall, the production Ghibli looks better and there's more character in the design than the com-gen Quattroporticina. This work rates a B.

Audi's second-generation Q7 hasn't been greeted with rapturous applause for its styling, but it could have ended up looking like the com-gen from four years earlier. It is hard to find a single styling detail shared in the two images… maybe the four-ringed Audi badge on the grille? What this tells us is that the Q7's styling certainly wasn't locked in place as long ago as 2011. The artist couldn't have got things so wrong without working from very poor information.

While the com-gen could have been showing an evolutionary stage in development from the styling of the first-generation Q7, the second-generation Q7 has turned out much more angular than anticipated. Somehow, the production car looks like it's sitting back on its haunches, whereas the vehicle in the com-gen looks like it's raised at the rear. Relative to the com-gen, the production car looks chunky and solid.

So there are five instances of renderings versus reality. We'll be back with more in coming weeks.