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1977 Star Wars Computer Graphics
Noryungi writes "The interestingly named 'Topless Robot' has a real trip down memory lane: how the computer graphics of the original Star Wars movie were made. The article points to this
YouTube video of a short documentary made by Larry Cuba, the original artist, that explains how he did it. In 1977."
The interestingly named "Topless Robot"
*click*
The space-ship consoles show CAD-drawings the ship aligning with landing pads. Also the astronauts debugging the supposedly broker communication module used graphics. Only these was faked with drafted animation cells because computer graphics wasnt advanced enough in the 1960s to this. There were only osilliscope vector graphics then. But Kubrick and advisers like Minsky were anticipating better graphics in the future.
The reason Larry Cuba could do real-time rendering in 1976 was that he was using a vector graphics display (http://www.cca.org/vector/). In a vector display, there are no pixels. There is no video RAM. Instead, there is a list of (x y) pairs (a list of positions on the screen, each with an off/on flag). The controller simply loops through the list over and over: the (x y) are fed to digital-to-analog converters, which drive the left/right and up/down deflectors for the CRT's electron beam. The on/off flags turn the beam on and off. In other words, it's just a big oscilloscope, with the signal replaced by a list of numbers. The longer the list, the more time it takes to traverse it and draw it, the lower the refresh rate, and the greater the flicker.
If you stick to black and white, you don't need a CRT mask to separately illuminate the red, green and blue phosphor dots. Without this mask, you can get some very sharp images.
If Cuba were using pixels instead, he would have needed megabytes to hold an image. I doubt anyone could afford a megabyte. Moreover, I doubt that in 1976 the electronics was fast enough to even read an image's bytes and turn it into a CRT signal. And that's just displaying the image on the screen. To create the image in the first place, he would have needed, for each line segment, to fill in all the pixels from endpoint to endpoint. There's no way he could have filled that many pixels in real time. But with a vector display, filling is done by the movement of the electron beam, and costs you zero computation.
Alejo
The first digital computer I programmed was an IBM 1800 built in 1966 (and was donated to our university in 1975 where I got my hands on it) so I well know the level of computer power available when 2001 ASO was filmed. Back then analog computers were more suitable than digital computers for many real world tasks. Anyone studying computer science then was expected to be able to build an analog circuit to solve differential equations for example, that way was faster than the digital methods at the time. It would have taken quite a while to render a movie scene with the 4K that was left of the 1800's RAM after the compiler/runtime was loaded.
Now, where was I? Oh yes, Get off my lawn!
You didn't cry during Wall-E? I mean, didn't either, it was just I hadn't dusted the room in a while and it was irritating my eyes.
*** someone what of a spoiler alert ***
If you ever watched the making of one of the Aliens movies you found out the slime from he aliens mouths is corn syrup. All that sweet smelling stuff free flowing over everything. After I found that out the aliens lost a lot of their scariness. I seen the slime drooling out of one of those alien's mouths and my brain goes "ooo candy".
CGI is like make-up; it's good for covering blemishes, but if it's obvious then you're probably doing it wrong.
The problem is that the film industry is to CGI what a ten year old girl is to make up; nothing and no one is safe.
The machine was a PDP-11. It was a PDP-11/45 running a one-of-a-kind graphics OS, called GRASS, the Graphics Symbiosis System written by Tom DeFanti, a professor at the University of Illinois at Chicago (then the University of Illinois at Chicago Circle). Tom's appointment then was to the Chemistry Dept.; the GRASS system was used primarily for molecular modeling. It drove an Evans & Sutherland Picture System, a giant $100,000 vector graphics engine worth five times what the PDP-11 was worth.
Larry's work pushed the system to its limits. His work was done at night, on the QT, with Tom's permission. This was done by giving Larry his own disk pack with a copy of the system on it. Larry's use of the system worked around all sorts of bugs in that relatively early version of GRASS. The film was made by pointing a (film) camera at the E&S screen, and running a macro which would render a frame, click the camera, render a frame, click the camera... While the PDP-11 system could in fact render the Death Star trench in real time, by the time you included all the little bits and frobs, the E&S took long enough to draw it that the display flickered. Hence the need to do frame-by-frame. Also, there was no frame-sync hardware in the system; the camera and display were connected only by the solenoid that tripped the camera shutter.
I played with that disk pack a year or two after the fact and it was a hoot to fly around the Death Star by hand. GRASS pioneered the interactive control of complex graphics, so all the position (and other) variables could trivially be tied to dials, etc. I was discouraged by one thing: the final version of the run had apparently been deleted from the disk. The only version I could find had the big "dish" directly on the equator of the Death Star, not at 45 degrees north latitude as in the film.
Years after that, I happened to talk to Larry Cuba by phone about something else, and asked him about that. He said the version I saw WAS the final version. Years after that, when I went to my "farewell to Star Wars viewing of Star Wars", I saw he was right. The plans shown to the rebels show the dish on the equator. Obviously the plans were fake. Those rebels were all dead men.