Which new games would you like to see on your VIC20?

[carlsson]

In the mean time, you can play the Napoleon Simulator by Ghislain, entered into the 4K category of the MiniGame Compo. Voting is going on right now, ending on the 30th of September. I was positively surprised that a such simple looking game could be so playable.

[carlsson]

A graphic difficulty about Archon is that the board consists of at least three background colours. Maybe more; I remember it cycles, but not if it involves more than black, white and neutral. Preferrably add two distinct foreground colours, and you have a slight graphic issue to tackle. You could do it with blocky low resolution graphics (4x8) using border colour for one player and auxillary colour (high nybble of 36878) for the other player and use character colour for different background. It would look quite ugly, but could work. Here's a mock-up using solid blocks rather than detailed graphics. Each graphic could have a resolution of 8x16 double width pixels (occupying 2x2 squares).



As an alternative, perhaps one can use raster timing to constantly change background colour for each square, but it sounds very time consuming and sensitive to timing faults.

[ral-clan]

A graphic difficulty about Archon is that the board consists of at least three background colours. Maybe more; I remember it cycles, but not if it involves more than black, white and neutral. Preferrably add two distinct foreground colours, and you have a slight graphic issue to tackle.

Perhaps it would be possible to use dithering to simulate shade changes on the squares that oscillate from dark to light....i.e. putting dots on every other pixel in the square in a checker-board (draughts) fashion.

Also, perhaps it would be possible to avoid using seperate colours for the game pieces by using one colour for the left side, and the same colour - but only drawing the outline of the the character forms with this colour - on the right side pieces.

[Thomas Hechelhammer]

As an alternative, perhaps one can use raster timing to constantly change background colour for each square, but it sounds very time consuming and sensitive to timing faults.

Hello Carlsson.

The foreground begins at rasterline x.
At rasterline x-1 you can initialize 2 CIA timer.
Timer 1 runs one screen and goes to zero each rasterline x-1 and produces an interrupt.
Timer 2 runs 16 rasterlines (2 chars), which means:
interrupt @ x-1: set auxiliary color 1 (start of squares)
interrupt @ x-1 +(16*1) : set auxiliary color 2
....
interrupt @ x-1 +(16*8) : set auxiliary color n
interrupt @ x-1 +(16*9) : set auxiliary color 0 (no more squares, end of playfield, no more changes)

When Timer 1 goes to zero: initialize timer 2 again

This method wouldn't be very time-consuming, you need a counter for a table which contains the values for the auxiliary-colors you set in the raster-range.

Timing isn't critical, when the next line -1 is reached (IRQ) you can poll the raster-register for better timing.

Using two timers will slow down the speed of the computer of 1/10 because we have more interrupts.

The timer-values and line x depend on either PAL or NTSC-VIC.


@Admin: It would make sense to split the discussion and move this part to a programming-section.

-- Thomas

[carlsson]

Hm, I was considering moving the whole thread into the Games section, but maybe it should be split into subtopics. If someone is serious about programming Archon, it could be a thread on its own (in Programming) and various techniques like the raster split you described could be evaluated if they are practically useful. If someone is developing another game, it can be another thread.

Currently we have Programming, Games and Programs (Basic or ML) sections; I don't know where WIP threads belong. On AtariAge, they have one section about homebrew games side by side to the programming sections.

[idrougge]

But pixel-soft-scrolling of the map-image would be impossible.

Aleksi Eeben's Dragonwing (my favourite VIC game) scrolls very softly, but then again it uses very few characters to build up its screen.

[Victragic]

Hi all,

first time post, so I'm fresh faced.. I recently started messing around with VICE, aproximately 20 years after I got rid of my first VIC20..

I did buy a second machine circa 1993, but unfortunately the power supply burned out rather quickly, so it ended up in the trash. Pity, as I thought I had picked up a bargain and finally had the HES monitor I never could afford. It's nice mucking around with emulators, but not the same as the real machine..

I don't know if it has been tried, but I would think that a version of Elite on the VIC20 (32k of course) would be a pinnacle of an achievement.

The original Elite for BBC was written for a 32k machine, as was the port to the Electron.. the Electron might be the better version to try to port as the speed of the machine is most similar to the Vic.. of course the architectures of the machines are completely different but how hard could it be? The graphics display parts could be adapted from the 64 version I think.

Reason I think Elite would be a good project to convert is that I feel that vector-style graphic effects on the VIC suffer less in conversion than full-colour 'sprite'-based graphics. I would probably expand the screen to a 28x35 matrix (PAL) which is perfect viewing for VICE, but probably not great for a real VIC as most TVs, monitors would use over-scan and lose the edges - still it wouldn't matter much for such a game. Just a personal thing, I've always hated the VIC borders.

Has anyone attempted Elite? Am I insane for considering it? Are there any inherent problems anyone can foresee with this?

Cheers,
-G

[ral-clan]

Reason I think Elite would be a good project to convert is that I feel that vector-style graphic effects on the VIC suffer less in conversion than full-colour 'sprite'-based graphics.

The only true vector graphics game I can think of on the Amiga (i.e. true vector graphics rather than simulated bitmapped ones like Omega Race) is BLACK HOLE.

EDIT: Oops I mean VIC-20 not Amiga. Just got off Amiga.org!

[Victragic]

The only true vector graphics game I can think of on the Amiga (i.e. true vector graphics rather than simulated bitmapped ones like Omega Race) is BLACK HOLE.

Yes, I think even Battlezone cheated with the graphics.. and the graphics in Black Hole are rather jerky at best.. so perhaps I take it back.

Still, would like to see VIC Elite even if it ran at 4 fps..

[orion70]

In theory, VIC is faster than C64, isn't it? (I can feel the difference playing those damned platform games - monsters are always catching me faster than their C64 counterparts - or it's my impression)?
So, provided you have enough RAM, Elite shoudn't be a problem. I vaguely remember a demo (A. Eeben's?) in which a solid colorful cube was rotating on the screen, soon followed by a semi-transparent version (!!!). And it was for UNEXPANDED VIC!
Let us not underrate the possibilities of our beloved machine...

[Mike]

I do have a line-routine in my library for the 160x192 bitmapped screen, that does 30000 pixels per second on the VIC.

I also wrote a small demo (rotating wire-frame-icosaeder inside cube); with 20 corners and 42 lines, using an off-screen buffer - which indeed runs at 4-5 frames per second. This is only a demo, I concentrated on clean mathematics inside, and so the rotate-and-project routine internally uses *extremely big* trig tables, and 32-bit arithmetics. This surely could be stripped down for a game like Elite.

The RAM is not that big problem. One could use an overlay scheme, so that different parts of the game are fast-loaded from floppy. You don't need the vector-part loaded, when you're docked at a station.

Michael

[ral-clan]

I vaguely remember a demo (A. Eeben's?) in which a solid colorful cube was rotating on the screen, soon followed by a semi-transparent version (!!!). And it was for UNEXPANDED VIC!
Let us not underrate the possibilities of our beloved machine...

Exactly what I was thinking. Yes, Black Hole was jerky. But remember these were the first programs of their type. Later on people had years to experiment on the C64 and then again on the VIC now that retro-computing is popular. They've figured out how to do some amazing stuff. So I think Elite is not far off.

Actually, are Medieval Joust or Capture the Flag vector based games? Those cartridge images won't run on my emulator (or even my real VIC-20 correctly). Is there a fixed image for either?

[PhotoJim]

This would be completely indulgent... but why not a z-code interpreter for the VIC?

Then we could play Infocom games... and some of the newer Inform games that have been written more recently.

22 columns would make it slightly painful but since so many of us have expanded VICs now, assuming a 32K (or even a 40K) VIC isn't too ridiculous of an assumption. The slightly faster processing of the VIC versus the 64 would mean the games would be reasonably playable.

Just because... the best reason to write something, right?

[carlsson]

I'm unsure how versatile the Z-machine implementations on the C64 are, but it is something I thought about as well, except I'm no adventure game player. The speed difference between VIC and 64 isn't that great that you'd notice an adventure game fly across the screen, but of course, a smaller display holds less text so maybe more scrolling would occur.

[eslapion]

Actually, are Medieval Joust or Capture the Flag vector based games? Those cartridge images won't run on my emulator (or even my real VIC-20 correctly). Is there a fixed image for either?

Capture the Flag runs just fine here, both on my real VIC and VICE XVIC.

I guess that's one of the various pieces of software I will have to show running with my expander on december 2nd.