If you've watched movies in the past 10 years, you've probably at some point complained about horrible CG, because you movie viewers are ungrateful little jackanapes.
Every time CG goes well and blends seamlessly into the movie (I bet you didn't know it was used in Brokeback Mountain), people rave about the amazing acting performances and the wonderful storyline and maybe the great soundtrack, and every time it goes wrong, everyone talks about how CG is terrible and is ruining movies.
I'm not joking, watch the video.
But that's OK, whatever, it's a job, nobody says thank you to accountants and insurance underwriters either. I can't brag to anyone about having worked on The Mummy: Tomb of the Dragon Emperor, but it put food on the table. But you know, as long as we're criticizing crappy CG, I thought maybe you'd like to know more about the details of how each terrible disaster unfolds behind the scenes, and more importantly, who to point fingers at.
Here's some of the more common complaints:
#7. Skin Looks Like Plastic
One of the creepier CG sins is to make skin look like plastic. This was only one of many many things wrong with the Scorpion King character above, who actually only appeared in scorpion king form in The Mummy Returns and not in any of the three movies actually named The Scorpion King, because Hollywood likes to confuse us. (Yes, it had two direct-to-DVD sequels. No, nobody watched them.)
When moviegoers say skin "looks like plastic," it can mean a few things. Sometimes they mean faces are rigid and motionless, as if they were made of hard plastic like some kind of creepy doll, which is usually a rigging problem, which I'll talk about later. Sometimes they mean the skin has the texture of plastic, like their face has been shellacked.
Sure, this was 11 years ago, but let us note that the Rock lent his face to this hilariously shameful visual effect the same year that the first Lord of the Rings movie came out.
They hadn't reached their full potential yet (Gollum comes along in the later movies), but clearly, plastic-Rock-head-pasted-on-monster was not "the best you could expect from CG at the time" by any means.
One of the (numerous) things they would do to make Gollum look much, much less like a bad video game character than the Scorpion King was to make his skin not look like frickin plastic. The person responsible for this is the person who writes the shaders. When a character is modeled, or "sculpted" in 3-D, at first it has no color. When modelers show their work for approval, it usually looks like a statue made of dull gray clay.
In fact, freelancers will sell models at this stage. This one is going for $275 on TurboSquid:
A shader writer is a person who writes a program that tells the computer how to "paint" the model -- not just what colors, but how shiny or dull, how bumpy or smooth, how transparent or reflective it is, depending on a bunch of factors, like whether it's facing you or you're looking at it at an angle. Lots of science.
Skin is made of a lot of layers, so it's really complex, and they were really far from figuring it out back when Toy Story was made, for example, which partially drove the decision to make the movie about a lot of plastic toys and not about humans with skin.
The big breakthrough was a thing called subsurface scattering. Read that linked tutorial if you want to find out more about it, but basically, it accounts for light bouncing around through all the layers of the skin so your character stops looking like the picture on the left and starts looking like the picture on the right:
