TC <do-not-reply@i-do get-enough-spam-already-2498.com> wrote:
> Warp, don't take this bad. I mean not to insult you in any way - when 
> posting on the net things occasionally sound worse than they are meant. so 
> peace ;-)

  You seem to assume that I'm some 15yo whose first computer was a PS2.

> I suppose you will not believe me, but a GAME back then was not what you 
> would consider a game. On the VIC you had exactly 3.583 BYTES of free memory 
> (not kilo, mega or gigabytes).

  The Atari 2600 makes it better: 128 bytes of RAM. Yes, so?

  And exactly what do you think I consider a game? Why wouldn't a VIC-20
or an Atari 2600 game be a game? Primitive (even by the time they still
were popular)? Definitely. Playable games? Why not?

> Every single byte did count ;-) Hell, we even 
> used half-bytes, which were called nibbles. I dimly remember things like 
> binary coded decimals - some things are best forgotten.

  I really don't understand what binary coded decimals have to do with
space optimizations (given that they actually *waste* space compared to
native binary representation of numbers).

> The sound mentioned in the wikipedia-article did consist of three beepers, a 
> noise-generator and a way to control the loudness for all four:

> Poke 36874, 128 : REM bass - range between 128-255
> Poke 36874, 164 : REM tenor - range between 128-255
> Poke 36874, 255 : REM soprano - range between 128-255
> Poke 36874, 128 : REM noise - range between 128-255
> Poke 36874, 15 : REM loundness, range between 0-15

  That's luxury compared to the ZX Spectrum 48, which had one single
beeper and nothing else. Games and programs had to be content with that.
(Regardless, some games achieved pretty impressive music, taking into
account the limitation.)

> Now, every really professional arcade game was programmed not in BASIC but 
> in 6502 assembler. I was talking about using BASIC to draw the graph. 
> Assembler was faster, of course.

  I still don't buy a *sine wave* taking *10 minutes* to draw, even if you
used BASIC.

  Let's put it this way: The Vic-20 had a resolution of 176 x 184 pixels,
which means that to draw a regular sine wave you would need to evaluate
it 176 times and draw 176 pixels on screen for a full-width graphic.

  If that takes 10 minutes it means that evaluating the sine function once
and drawing one pixel would take 3.4 seconds, ie. about 3.75 million clock
cycles (for a 1.1 MHz 6502 CPU)

  Maybe if you implemented the sine function evaluation as the evaluation
of a fourier series, in BASIC, then it *might* take that 3.75 million clock
cycles to evaluate it once. If you do a lot of extra work. And probably using
a lot more accuracy than the vertical screen resolution would need.

  I don't know if the Vic-20 BASIC had internal support for evaluating the
sine function, but if it did, I would be rather surprised if evaluating it
once would take 3.4 seconds.

> I learned BASIC by typing in the listings of games and other programs. The 
> listings were to be found in computer magazines or books and had to be typed 
> in by hand.

  At least you didn't type gigantic hex listings, like me...

> Later, on the C64, a way better and faster computer, when you were doing a 
> flood-fill with Simon's BASIC you could sit by and watch the picture to 
> complete.

  That would tell something about the speed of the BASIC interpreter rather
than the speed of the computer itself, given that eg. the "Second Reality"
demo has been "ported" to the C64, all parts included (including all the
real-time 3D graphics). And it's not even the best demo for the C64 in
existence. (Granted, the C64 version of "Second Reality" doesn't look exactly
as good as the PC version, but it looks very impressive taking into accout
the hardware it's running on.)

> All this brings back rather fond memories and it makes me feel REALLY OLD 
> for the first time...

  These are some pictures I drew with my first computer, a Spectrum 128:
http://warp.povusers.org/SpectrumPics/

  (I was able to salvage these pictures from an old casette where I had saved
them, by using an emulator which was able to interpret the modulated data.
The Spectrum was not as capable graphically as eg. the NES, and had some
pretty bad limitations (described in that page), but with some effort you
could get pretty decent pictures for the era.)

> Nowadays you are very lucky, more lucky than you will ever know. 

  Please stop assuming I'm a 15yo.

-- 
                                                          - Warp

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