Software sprites?

nippur72 · Post by **nippur72** » Fri May 29, 2009 12:37 pm

OK, I've checked it on a real (PAL) machine and it works perfectly: it's as smooth as an hardware sprite and with no IRQ timing problems at all. Amazingly fluid.

On the emulation side, I still get problems--I've tested several VICE versions ranging from 1.18 to 2.1 and all behave differently from a real machine. Mess emulator behaves even worse than VICE because it displays strange dots artifacts on the demo program I've compiled.

If you want to check yourself, here is the binary .prg:

http://xoomer.virgilio.it/aporcino/Vic20/primer.prg

it's nothing else than your "sample.s" with a custom IRQ that flips screen color on each IRQ call. My idea is that, if everything is OK, the colour change should be perceived as a plain color flicker. If timing is wrong, the flickering should be fuzzy and blocky.

If you check it, do that in PAL and NTSC and tell me if in your emulator it runs as expected.

@nbla000: this SSS thing is so intriguing that I've come out of my lurk mode

are you interested in it too?

rhurst · Post by **rhurst** » Fri May 29, 2009 1:24 pm

I ran your modified primer.prg on VICE 2.1 in both NTSC and PAL modes -- perfect.

I transferred the same binary over to my real NTSC VIC -- perfect.

I also ran it using MESS 0.131 in NTSC mode -- runs, but there is a noticeable dot artifact creeping up the display on every redraw. Other than that, it ran closely like the real thing.

I haven't the foggiest as to the source of the issue you are seeing.

nbla000 · Post by **nbla000** » Sat May 30, 2009 9:59 am

nippur72 wrote:@nbla000: this SSS thing is so intriguing that I've come out of my lurk mode are you interested in it too?

Why not ? contact me in PM or via Email.

AmiDog · Post by **AmiDog** » Mon Jun 01, 2009 12:39 am

nippur72 wrote:On the emulation side, I still get problems--I've tested several VICE versions ranging from 1.18 to 2.1 and all behave differently from a real machine.

Maybe it's the emulator that's skipping frames? What computer are you using?

nippur72 · Post by **nippur72** » Mon Jun 01, 2009 10:46 am

AmiDog wrote:Maybe it's the emulator that's skipping frames? What computer are you using?

I suspect the emulator isn't able to correctly refresh the video page when SSSFLIP is called. Don't know why. I use an AMD dual core @1.6Ghz and a 3d video card, so I suppose it should be fast enough.

Gary_Leeds · Post by **Gary_Leeds** » Mon Jun 01, 2009 4:38 pm

Just reading back over this thread and coupling it with a post on one of the plus 4 forums. You say 256 "simple" sprites could be handled. If someone had the skills and time would Lemmings be at all possible on the Vic? An open source project for the DS already exists with the source here http://www.mrdictionary.net/lemmings/le ... downloads/

Could be a very interesting project, just wish I had the skills to do it

rhurst · Post by **rhurst** » Tue Jun 02, 2009 4:32 am

... would Lemmings be at all possible on the Vic?

Sure, but given the VIC real estate and speed, I would not attempt to save more than 10 Lemmings on any given level. Lemmings don't move that fast to begin with, so all "active" Lemmings do not have to be redrawn every frame.

I believe the key would be its UI ... since Lemmings worked with a mouse / trackball, using FKEYs to switch the action button and programming a smooth target pointer for the joystick is essential.

I just wonder how acceptable a translated game like that on VIC could turn out, because my attraction to playing Lemmings was its scenery (rolling grass hills, caves, etc.) with a groovy upbeat tune that was easy to march to.

... the skills to do it

Given those parameters with VIC as the target, it would be very challenging. At the very least, you'd need Carlsson to do the music work!

English Invader · Post by **English Invader** » Tue Jun 02, 2009 6:30 am

I have a slightly less challenging proposition. Ghostbusters.

carlsson · Post by **carlsson** » Tue Jun 02, 2009 6:57 am

Some day I'll find time to have a look at this sprite library too. Since I generally don't have the patience to make perfect ports of existing games, I would probably rather try to make a loose cover or variant.

Besides the more unique titles, the more people will feel an urge to get a VIC-20. People already have played Lemmings, Ghostbusters, Sim City and all the others for decades.

rhurst · Post by **rhurst** » Thu Sep 10, 2009 7:18 am

FYI, I merged (using the nifty pygtk-based utility: meld) the latest updated source to Quikman 8k with the included demo in this package using the newer sprite routines.

rhurst · Post by **rhurst** » Tue Oct 06, 2009 7:33 pm

Using the M.E.S.S. debugger, I discovered that SSSPOKE, SSSREAD, and SSSCOMMIT were burning up extra CPU cycles, thus reducing precious framerates. Optimizations were put in, and tested with the new Quikman+8k and Omega Fury. I think both games play much faster more evenly than before -- and perhaps more enjoyable.

The primer sources, fixed binaries, and demos all have been updated and re-compiled in this archive. Enjoy!

rhurst · Post by **rhurst** » Sat Oct 10, 2009 9:28 am

Posted an update to this archive which includes fixes to the documentation and minor patches to the primer sources.

rhurst · Post by **rhurst** » Thu Jan 21, 2010 10:52 am

FYI, I am enhancing this software more for the following:

- flag for collision-detection (using it now for WIP: Berzerk MMX)
- primer for CC65
- primer for BASIC and other assemblers
- other optimizations

More to follow as Berzerk matures. For those interested in previews, download it here.

Just press FIRE or any key after it RUNs, to properly seed the random number generator. If you have quick reflexes, you might still be able to shoot yourself in the foot!

Pedro Lambrini · Post by **Pedro Lambrini** » Thu Jan 21, 2010 11:28 am

Looking good! You,sir, are awesome!

nippur72 · Post by **nippur72** » Thu Jan 21, 2010 11:30 am

rhurst wrote:flag for collision-detection (using it now for WIP: Berzerk MMX)

two great news! Berzerk working in progress and collision detection!!!