In what language is this animation written?
The Amiga Boing Ball Explained
21–30 of 65 posts
Re: The Amiga Boing Ball Explained
#22Obligatory link any time palette cycling images are mentioned: http://www.effectgames.com/demos/canvascycle/?sound=0 All images there are completely static 256 color bitmaps with only the mapping from color index to RGB value changed.
And, newly obligatory link to the GDC talk where the artist explains his technique.
http://www.gdcvault.com/play/1023586/8-Bit-8-Bitish-Graphics
Re: The Amiga Boing Ball Explained
#23A 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 might be obvious from the name, but there's also just one bit per pixel in a bitplane, and then you stack five bitplanes to get 32 colors. You can have different offsets into each bitplane, which is why the grid could stay in the same place while the ball bounced. The Amiga only supported bitplanes and not "chunky" modes like VGA where you have one byte per pixel. This made graphics with 256 colors (supported by t…
The offsets were measured in bits rather than bytes? That must have been a lot of engineering work.
Re: The Amiga Boing Ball Explained
#24There is a better and longer explanation of this effect in The Future Was There if you are interested.
Re: The Amiga Boing Ball Explained
#25Here'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…
Also, about a minute into the video is a clip of the ball bouncing, which is a lot more impressive than the static ball in the linked article.
Re: The Amiga Boing Ball Explained
#26A 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…
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 said, the tight coupling of CPU, RAM and the custom chips was perhaps the Amiga's Achilles heel. While on the PC you could switch out the various parts, the Amiga, at least on the A500, A600 and A1200, could not.
Re: The Amiga Boing Ball Explained
#27Earlier quoted context omitted.
Would be hard to sleep in those houses with that waterfall crashing ad infinitum...
We stayed in a mountain bungalow during summer vacation, there was a waterfall close enough to hear (and be loud) but far enough away that it's noise sounded like a pleasant version of TV static. I had my best night's sleep in years. My theory was that it drowned out ambient bumps and crashes that usually wake me up at night.
I recall camping at some relatives that had a waterfall near enough that you heard it any time you were outside. After about the second day or so you hardly even noticed.
Re: The Amiga Boing Ball Explained
#28Earlier quoted context omitted.
It might be obvious from the name, but there's also just one bit per pixel in a bitplane, and then you stack five bitplanes to get 32 colors. You can have different offsets into each bitplane, which is why the grid could stay in the same place while the ball bounced. The Amiga only supported bitplanes and not "chunky" modes like VGA where you have one byte per pixel. This made graphics with 256 colors (supported by t…
The offsets were measured in bits rather than bytes? That must have been a lot of engineering work.
If I remember correctly, the offsets were measured in words (16 bits on the M68k), and then you had scroll registers where you could offset with 0-15 pixels.
This was complicated a bit since you only had two scroll registers, one for even and one for odd bitplanes.
No idea how this was implemented in hardware.
Re: The Amiga Boing Ball Explained
#29A 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 might be obvious from the name, but there's also just one bit per pixel in a bitplane, and then you stack five bitplanes to get 32 colors. You can have different offsets into each bitplane, which is why the grid could stay in the same place while the ball bounced. The Amiga only supported bitplanes and not "chunky" modes like VGA where you have one byte per pixel. This made graphics with 256 colors (supported by t…
This also let you make "memory peekers". It was just a simple assembly program that would offset the pointer to a bitplane based on the mouse vertical movement. You could "look" at the RAM and it was one way to rip images since you would see the bitmaps of images from the game still in RAM after the reset.
Re: The Amiga Boing Ball Explained
#30A 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…
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 music , the Amiga soundchip was eaqually powerfull and the soundblaster card, although it could play better sound, was absolutely nowhere to actually mix sound. Oh yes, I missed the Amiga :-) Fortunaltely, the PC took over, so what I've learnt chasing the Amiga is actually useful :-)