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The Amiga Boing Ball Explained

amiga.lychesis.net

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Re: The Amiga Boing Ball Explained

#31

Post by bluedino »

anexprogrammer wrote: post #14
Luc wrote: post #6

A bitplane is a region of memory rendered as pixels. The Amiga hardware allowed you to (basically) define a width and height for the region, as well as a x,y offset. So by e.g. increasing the x-offset you could scroll horizontally through a bitplane with a width larger than the screen's. The ball is in the middle of a large empty bitplane. By simply changing the offset values it bounces around the screen. The graphic…

It's worth mentioning the reveal, which the page omits entirely, and was the astonishing bit of the CES demo at the time. In the original demo they were showing the normal desktop screen, showing window dragging, resizing, showing text editors, clocks, shell and what not. Running 640x480 4 colour. The whole time you could hear the bang bang of the boing ball bouncing, but see nothing. At some point a viewer asks "wha…

Windows let each application (or even window, it's been a long time I don't remember the specifics) define its own palette in 256-color (8-bit) mode. You had reserved colors to make sure the gui looked the same but you'd get all kinds of strange artifacts when you switched to an application that had a custom palette but you could still see other applications windows.

It was years where you had to make the trade off of color depth and related display quirkiness at the expense of speed and performance

Re: The Amiga Boing Ball Explained

#34

Post by anexprogrammer »

bluedino wrote: post #31
anexprogrammer wrote: post #14

Earlier quoted context omitted.

It's worth mentioning the reveal, which the page omits entirely, and was the astonishing bit of the CES demo at the time. In the original demo they were showing the normal desktop screen, showing window dragging, resizing, showing text editors, clocks, shell and what not. Running 640x480 4 colour. The whole time you could hear the bang bang of the boing ball bouncing, but see nothing. At some point a viewer asks "wha…

Windows let each application (or even window, it's been a long time I don't remember the specifics) define its own palette in 256-color (8-bit) mode. You had reserved colors to make sure the gui looked the same but you'd get all kinds of strange artifacts when you switched to an application that had a custom palette but you could still see other applications windows. It was years where you had to make the trade off o…

The fun days of switching your new £300 graphics card to 16 or 24 bit mode, moving a window, and watching Windows redraw every line and icon. Step. By. Painful. Step.

Re: The Amiga Boing Ball Explained

#35

Post by hinkley »

Wait, that's how it worked? That's it? It was a trick?

That demo was my introduction to the Amiga. Whenever I met an Amiga fan later in life I would picture that demo in my head.

Adult, programmer me knows all too well that demos are marketing material, aka "lies you can't be sued for", but really faking 3D rendering is pretty low even by marketing standards. I am extremely disappointed.

This kind of screws with the memories of some interactions I've had with old fans over the years.

Re: The Amiga Boing Ball Explained

#36

Post by anexprogrammer »

digi_owl wrote: post #26
anexprogrammer wrote: post #14

Earlier quoted context omitted.

It's worth mentioning the reveal, which the page omits entirely, and was the astonishing bit of the CES demo at the time. In the original demo they were showing the normal desktop screen, showing window dragging, resizing, showing text editors, clocks, shell and what not. Running 640x480 4 colour. The whole time you could hear the bang bang of the boing ball bouncing, but see nothing. At some point a viewer asks "wha…

While i own an A500 (still sitting in the basement) i was too young to really grasp what i was dealing with. Recently i learned that the Amiga was effectively two computers in one. you had the 68k doing its thing, and then you had the custom chips doing their thing, and in the middle you had a shared RAM pool. I guess to a degree the current CPU+GPU setup comes close, but that on the Amiga the GPU had priority. That…

It's hard trying to answer this briefly. Hope it doesn't come out meaningless!

It's comparable with current CPU+GPU but on a vastly simpler scale. The copper only had 3 instructions! Blitter, well most things, were DMA controlled but the whole chispet had a ton of special registers that both CPU and copper could get at. You could set what got priority. Coders had to learn to wait on blits as anything else - OS as you moved a window, another app or screen could have got it first. Hence why many games just hit the hardware - keep it simple, and single threaded, and to hell with the OS. :)

About chip memory. Amigas had two types of memory Chip RAM and Fast RAM. Chip could be accessed by CPU and any of the chips, Fast RAM just the processor for programs and data. Modern CPU+GPU has two separate pools of RAM linked via the PCIe. If there were a similar architecture to the Amiga, but with modern complex silicon and design, I'm sure games coders would have dreamed up a few extra effects and tricks. Or maybe it wouldn't matter any more with the vast speeds we now reach, I don't know.

Incidentally that tight linking, display coprocessing, along with the DMA channels, and readily available genlock, is why it ended up a niche success in broadcast. Nothing else apart from £10,000+ dedicated things like a Quantel Paintbox (who bizarrely still exist) could touch it, especially after the Video Toaster came along.

The chipset needn't have been the achilles heel if Commodore had not been run by an asset stripping moron at the time. Designs were being done for follow on sets, but never made it, and we got AGA (a fraction of AAA) years late. I think they started on AAA in 87, and cancelled it or put it on hold probably a dozen times. The 3000+ was an astonishing prototype machine that only existed on Dave Haynie's desk, for ages. Commodore gave us the lousy cost cutting 4000 with IDE not SCSI as follow up.

Re: The Amiga Boing Ball Explained

#37

Post by anexprogrammer »

wiz21c wrote: post #30
anexprogrammer wrote: post #14

Earlier quoted context omitted.

It's worth mentioning the reveal, which the page omits entirely, and was the astonishing bit of the CES demo at the time. In the original demo they were showing the normal desktop screen, showing window dragging, resizing, showing text editors, clocks, shell and what not. Running 640x480 4 colour. The whole time you could hear the bang bang of the boing ball bouncing, but see nothing. At some point a viewer asks "wha…

Having my dad buying an IBM PC with a CGA monitor, I can't say how much you are right. The Amiga graphics architecture was so much above everything at the time... Few years after that I wen into the demoscene and it was horribly difficult to achieve what the copper CPU could do... You had to time scanline readline with devious accuracy, change palette registers in non obvious ways, atc. And don't even talk about the…

Yeah me too. I had great fun and learnt so much. When I ended up doing a little Windows programming at work some years later - I couldn't believe how horrible it was compared to Intuition. No surprise my career majored on *nix. :)

Re: The Amiga Boing Ball Explained

#39

Post by PhasmaFelis »

anexprogrammer wrote: post #14
Luc wrote: post #6

A bitplane is a region of memory rendered as pixels. The Amiga hardware allowed you to (basically) define a width and height for the region, as well as a x,y offset. So by e.g. increasing the x-offset you could scroll horizontally through a bitplane with a width larger than the screen's. The ball is in the middle of a large empty bitplane. By simply changing the offset values it bounces around the screen. The graphic…

It's worth mentioning the reveal, which the page omits entirely, and was the astonishing bit of the CES demo at the time. In the original demo they were showing the normal desktop screen, showing window dragging, resizing, showing text editors, clocks, shell and what not. Running 640x480 4 colour. The whole time you could hear the bang bang of the boing ball bouncing, but see nothing. At some point a viewer asks "wha…

> In its day, that was almost unbelievable. PCs had just got 16 colour EGA and switching res resulted in a couple of seconds of monitor blanking or losing sync as it switched.

And still does. It's crazy.

Re: The Amiga Boing Ball Explained

#40

Post by toufka »

Arjuna wrote: post #4

Here's a short interview with Dale Luck, discussing the Boing Ball. I like how they came up with the sound for it: https://www.youtube.com/watch?v=cJcO628yCcU For readers following along at home, R.J. Mical [1] was a co-inventor of the Atari Lynx [2]: "Under the auspices of a game company called Epyx I was co-inventor of the first color hand-held game system, the Lynx, which finally was acquired by Atari. I was co-de…

The bouncing sound: took a platic bat (used for working out 'disagreements') and hit an alumimum garage door while digitizing the interior sound of the garage with an apple II, and masaging the digital data to play on the Amiga.
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