A round shaped LCD screen

Back in the early days of coin-op video games, when we first had x-y monitors (remember Asteroids?), we dreamed of having new display hardware based on r-theta displays. So you could rotate the screen (change theta) and then scale it by changing r.

Those whining hardware guys said they could not do it (circa 1978)

Sorry, talk about off topic!

There is no "x" in my email address.

Though that's exactly what early radar systems did.

They uses a round tube, with deflection on one axis, the deflection assembly was motorized to spin around the tube. Thus the motor position gives theta, and the electromagnetic deflection gives r.

Still, for most arcade games, having a polar coordinate display would have caused more trouble than it solved. Even in games where the majority of the action takes place in a polar coordinate space, lots of things would have to be transformed since you often need to be able to rotate objects around an origin independent of the center of the global coordinate system. Also, displaying the score and other text messages would have similar problems, unless you actually wanted them displayed "wrapped around a circle".

Eric

I expect the aircraft market could bear the cost too.

Graham

Hmmmmm - I feel a post to abse coming on !

Graham

Oh yeah, the aviation market is booming.

Not.

Still doesn't explain b) There are lots of examples of circular glass around me, flashlight lens, vanity mirror, telescope, old radio bezel, spirit level. Rectangular LCDs are much more convenient and efficient to make and connect. I know some guys on another newsgroup who might like a small circular LCD to replace a 6E5 but I suspect it will take a few more years to become cost effective.

Peter

It's fairly common to break the corners off a monochrome LCD to allow it to fit within a circular or elliptical outline. Cheaper than a true circular outline.

Best regards, Spehro Pefhany

Apparently, nobody's paying attention to the little datum that they go in square holes. It's not that hard to draw round things on a rectangular screen, you know.

Cheers! Rich

I find that rather hard to believe. If you break the corners off, the LC will leak out of the D.

Yeah, okay, they break the corners off the glass *before* they assemble and seal it.

It's was just intended as a description of the (irregular octagon) shape of the LCD, not a description of the manufacturing process, wot?

Best regards, Spehro Pefhany

.... and it's not particularly pleasant stuff. Luckily, there is not much of it.

Yes, that would have been confusing.

What we were talking about was being able to have multiple nested objects r-theta transformed. This could not have been done with just display hardware.

This is like having a 3d object that is transformed relative to a parent object. So the universe (the display) would probably not be rotated or scaled, but individual items would be. So for example you could rotate and scale a car and its wheels would also rotate (and be scaled to match the car size) within the new frame of reference. This was speculated on way before a semi-true semi-real-time 3d transformation was possible.

Regards ~Steve There is no "x" in my email address.