new game I'm writing, with screenshot.

David Murray

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Oct 21, 2009, 5:45:44 PM10/21/09

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I decided to port Flash Attack to the VIC-20. I've been working on it
for days, it is all 100% assembler and does require 24K of RAM in
order to run. The code is only 2.5K but the map is very large, and
requires a lot of space. However, if there is sufficient demand, I
think I could shrink a few things down and maybe make it work on an
unexpanded VIC or maybe with a 3K expansion...

http://galaxy22.dyndns.org/vic20/game-screen2.png

So far it runs very fast, so I'm happy with the graphics routines, but
much of the game logic isn't done yet so the only thing you can do is
drive around (and drive right through walls too!)

Clocky

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Oct 21, 2009, 8:17:59 PM10/21/09

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It's always cool to see new VIC-20 development. Personally I think you
should aim to get it running on a VIC-20 with an 3k, 8k or 16k RAM expansion
since they are probably the most common expansions. Maybe you could break
the map up and load from disk as needed?

David Murray

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Oct 21, 2009, 8:41:35 PM10/21/09

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> It's always cool to see new VIC-20 development. Personally I think you
> should aim to get it running on a VIC-20 with an 3k, 8k or 16k RAM expansion
> since they are probably the most common expansions. Maybe you could break
> the map up and load from disk as needed?

Loading from disk is out of the question. In many ways this game will
be like a real-time strategy game with several units doing their own
thing and operating autonomously. So the map has to be available in
memory at all times. However, right now the game is working very
inefficient on memory because I have things spread out a lot because
I'm not sure how large the code is going to be. I think it may be
possible when I'm done to get the game working on a 16K VIC-20 without
sacrificing any features, but I'm not sure yet. After that, it may
be possible to use a smaller map and get it working on an 8K.. But the
truth is, once I finish working on this, I plan to port it to the
C64. After doing coding on the VIC-20 I realized that 95% of this
code will work as-is on the C64 and will only require just a few
changes to make it work. After that, I may port it to the Plus/4.
Since the game doesn't use any sprites, the code is really portable.

DanSolo

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Oct 22, 2009, 7:22:59 AM10/22/09

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On Oct 21, 10:45 pm, David Murray <adri...@yahoo.com> wrote:
> does require 24K of RAM

> I think I could shrink a few things down and maybe make it work on an

> unexpanded VIC or maybe with a 3K expansion...

If it needs 24K now how could you get it down to 3.5K or 6.5K?

David Murray

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Oct 22, 2009, 8:07:44 AM10/22/09

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>
> If it needs 24K now how could you get it down to 3.5K or 6.5K?

Well, so far my code is only 1.5K in size. (amazing how small ML
compiles to!) And the map is using 16K of RAM, however it is only
using the first 4 bits of each byte. So I should be able to re-write
part of the code to compress that to 8K without sacrificing anything.
But I could make the map smaller, and possibly fit the whole thing
into 8K of RAM. Putting it on an unexpanded VIC would mean
significant sacrifice in size of the map, but it should be possible.

joecommodore

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Nov 1, 2009, 10:32:35 PM11/1/09

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Wow, cool, gonna be a two computer game?

Mayhem

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Nov 3, 2009, 6:32:33 AM11/3/09

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If you want more input for a Vic20 game, then joining the Denial forum
wouldn't be a bad idea...

David Murray

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Nov 3, 2009, 10:19:20 PM11/3/09

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On Nov 3, 5:32 am, Mayhem <Mayhem...@hotmail.com> wrote:
> If you want more input for a Vic20 game, then joining the Denial forum
> wouldn't be a bad idea...

Yeah.. been there weeks ago.. made several posts..