New interpretation of Pitfall! for PAL Vic + 16K
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- mrr19121970
- Vic 20 Nerd
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Re: New interpretation of Pitfall! for PAL Vic + 16K
I downloaded this some time back. I couldn't even remember infact. At 1st I loaded on the C64, didn't work. Then the VIC20 just now. Great work. Thanks
Re: New interpretation of Pitfall! for PAL Vic + 16K
I just downloaded this and tried it out (in emulation as I have no PAL VIC-20).
Really, really excellent! An amazing feat of programming. If was not already familiar with the VIC-20, you could have convinced me that the VIC does have hardware sprites based on the graphics in this game.
Really, really excellent! An amazing feat of programming. If was not already familiar with the VIC-20, you could have convinced me that the VIC does have hardware sprites based on the graphics in this game.
Music I've made with 1980s electronics, synths and other retro-instruments: http://theovoids.bandcamp.com
- mrr19121970
- Vic 20 Nerd
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- Joined: Tue Jan 19, 2016 9:22 am
- Location: Germany
- Occupation: IT service manager
Re: New interpretation of Pitfall! for PAL Vic + 16K
The original atari 2600 fitted into 4k. I am wondering why the vic20 needs 5x the memory. Anyone know ?
- Mike
- Herr VC
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Re: New interpretation of Pitfall! for PAL Vic + 16K
Several reasons: the Atari 2600 has no frame buffer at all, the whole display (including the PM graphics) comes from a few registers. When those aren't altered, the contents of a raster line are simply replicated.
On the VIC-20, with this implementation, you have the display routine which does the in-line splits of the background register for each raster and the colour FLI for the player character and the baddies in a big unrolled loop that runs in the interrupt and spans the address range $29xx..$42xx: ~6.5 KB, by far the biggest single routine in the game.
$1000..$1FFF is mostly dedicated to graphics data and tables, $2000..$2500 part of the game logic, $2500..$2900 another set of tables, $4200..$4D00 another part of the game logic, $4D00..$5000 once again some tables, $5000..$5FFF also mostly data structures interspersed with a few bits of code; surely a music player and sound effects routine are also placed around there.
...
Of course you could always try yourself to fit Pitfall! with all the described features into an unexpanded VIC-20. SCNR.
On the VIC-20, with this implementation, you have the display routine which does the in-line splits of the background register for each raster and the colour FLI for the player character and the baddies in a big unrolled loop that runs in the interrupt and spans the address range $29xx..$42xx: ~6.5 KB, by far the biggest single routine in the game.
$1000..$1FFF is mostly dedicated to graphics data and tables, $2000..$2500 part of the game logic, $2500..$2900 another set of tables, $4200..$4D00 another part of the game logic, $4D00..$5000 once again some tables, $5000..$5FFF also mostly data structures interspersed with a few bits of code; surely a music player and sound effects routine are also placed around there.
...
Of course you could always try yourself to fit Pitfall! with all the described features into an unexpanded VIC-20. SCNR.
- eslapion
- ultimate expander
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Re: New interpretation of Pitfall! for PAL Vic + 16K
This game and Robotic Liberation are among the 2 most important reasons why I am happy to have both NTSC and PAL VIC-20s.
Be normal.
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- Vic 20 Amateur
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Re: New interpretation of Pitfall! for PAL Vic + 16K
Now *this* is what a good port looks like. Bravo!
Re: New interpretation of Pitfall! for PAL Vic + 16K
I think this is absolutely amazing.
It doesn't even look and feel like a VIC-20 game.
Congratulations and thank you very much. It's a 10/10 from me.
It doesn't even look and feel like a VIC-20 game.
Congratulations and thank you very much. It's a 10/10 from me.