Conversion Capers: Rygar

[Nekoniaow]

It looks like many think that this is an actual conversion which is being discussed but it seems to me that CodeTapper initially meant this thread only as a thought exercise. This said, if it generates enough traction that's definitely an interesting project.

For reference:

Originally Posted by Codetapper

I've never seen a thread like this before so thought it might be an interesting idea for some of the programmers on here.

Let's imagine back in the late 80s or early 90s you were employed to convert a game to the Amiga. The boss has just given you the arcade machine and you've got to tell the other people helping you the approach you'll take.
[SNIP]
Coders, step up to the plate and scribble down your initial thoughts!

Originally Posted by Hewitson

I feel the need to argue with many of the posts in this thread. Is an accurate conversion of Rygar not possible with most coders? Possibly. Is it possible with someone who has a C64 level of dedication? Absolutely.

I guess this depends heavily on what you mean by "accurate" so this would require some elaboration.

If you mean same richness (not number) of colours, similarly shaped (but not identical) parallax scrolling, then IMO it might be doable in 32 colours and certainly in 16 colours. This said there might be moments when the parallax scrolling can't be blit (*) or done with sprites so it would have to go.

This said, as far as my post is concerned I welcome mentions of errors or simplifications I may have made. I am currently working on my own project so I am definitely interested in fixing the flaws in my reasonings.

(*) what would be the past conjugations of "to blit"?
Blit, blitted, blitten? Blit, blit, blit?

[sandruzzo]

About this project, I need this Stuff:

- Player's frames converder as sprite data.
- Enemies framse, as actuall Gfx, they will be bobs.
- Background's Gfx as tiles
- Levels' maps in order to pick up tiles and write the background.
- Weìll go for 32+ color on screen
- All the sprite enemies weapons and stuff like that we will push into first 3-4 bit-plane
- the lower portion of background, were main character go, we'll use the first 8-16 colors. So we can reduce bitplane bandwidth usage.
- the parallax scrolling foreground will use the first 2-3 bit plane. If have some left power we can try to add it

Gfx games dontì have to be pixel perfect, MUST BE BETTER
This game will target ocs/ecs machine plus 512k fast mem.

[dlfrsilver]

i'm currently getting the tiles, with the right palettes from the coin-op roms

OK, let see here what i got for a start :

[sandruzzo]

Originally Posted by dlfrsilver

i'm currently getting the tiles, with the right palettes from the coin-op roms

OK, let see here what i got for a start :

Nice Work!

Now, we need levelo tiles and map to put them on screen. I would like to start with scrolling, and see how with 32 colors things go..

[Retro-Nerd]

http://www.vgmaps.com/Atlas/Arcade/i...gendaryWarrior

[sandruzzo]

Originally Posted by Retro-Nerd

http://www.vgmaps.com/Atlas/Arcade/i...gendaryWarrior

Whitout word!! Nice!!:bow

Now we need al tiles put well on one gfx bitmap, and we need some sort of tiles map in order to blit them correctly!

[sandruzzo]

Before we start: Would you like Rygara ECS/OCS or Aga?

[dlfrsilver]

AGA would be the way to go for a start. Then ECS/OCS.

[sandruzzo]

So go for Aga? For this machine we will use dual-playfield, are you ok? For Aga quiet "simple" to do...

[Codetapper]

Originally Posted by Nekoniaow

I would reserve the rest for parallax scrolling assistance: when vertical walls scroll in/out or when a vertical section of tree is in the foreground.

There are many occasions where there are lots of full-screen-height trees on the screen.

It does not seem that hard to reproduce in many situations. There are many parts of the game where the foreground overlaps the background only over a relatively thin horizontal slice which means that all parts of the background which lie above can simply be hardware scrolled.

But that method means any object that overlaps both slices has to be drawn in 2 parts, complicating the code.

Even the places with trees in the foreground do not seem above reach: sprites could be used for the portion of the trees which are purely vertical and they could be repeated horizontally by sacrificing accuracy to the original. It's not that all obvious though but it's worth trying.

Have you played the first level? Half way through there are loads of different trees, with leaves, much wider than a couple of sprites would allow.

Why do you say "hide" the colour change?
The copper can wait anywhere on screen so you can change the background color at any pixel you want. Unless you want to have colourful edges you don't need sprites at all except for the top and bottom lines, and then you need only one since you can reuse it vertically.

You can't specify single pixel accuracy for colour changes with the copper on a 32 or 64 colour screen. There is always some kind of delay, which is the reason you see a very thin single pixel strip down the side of some games. They are trying to wait for the first (or last) pixel on a line and change the background colour from/to black, but by the time the copper gets another DMA slot to make the colour change, the exact pixel you wanted has gone.

Hence that sun effect you could probably have it look similar-ish, but without overlaying sprites to hide the edges or drawing pixels into the bitmap you can't get it exactly the same.

Having said that, I'm looking forward to seeing some progress on this!

[sandruzzo]

Work go well. I'm setting on the scroll routine. Just a little bit out of shape since my last Amiga stuff.

So far I'm working on OCS/ECS stuff. When some bugs gone I'm going to set all for AGA.

Some questions: Are we going to use DualPlayfield Mode? Would be better to use Interleved mode?

[tarr]

AGA would be a defeat: this is a 1986 game!

[sandruzzo]

Originally Posted by tarr

AGA would be a defeat: this is a 1986 game!

I just need to know what would be the first Target Machine.. There are some choice to do.

I've suggested to do for ocs/ecs plu 512k fast mem

[tarr]

ocs/ecs plu 512k should be the real challenge.

[Rebel-CD32]

I agree, OCS plus 512k. No, don't use Dual Playfield, there's no way to remap all the foregrounds and enemies to 7 colours without it looking like puke.

[sandruzzo]

Originally Posted by Rebel-CD32

I agree, OCS plus 512k. No, don't use Dual Playfield, there's no way to remap all the foregrounds and enemies to 7 colours without it looking like puke.

Dual Playfield, for Aga. I've suggested to start with 32 colors, and see what will happen.

BOB's will use the first 8-16 colors.

I nedd background gfx and tiles'map

[sandruzzo]

Any gfx to use Mates? Waiting for help.

[Amiten]

Hi, Rygar is one of my fav arcade game for sure, many coins of 25 pesetas I spend back in the time. Nice thread but there are some one making this game for Amiga?? In case yes ,wich lenguaje?? ASM ? C? Basic? Thanks

[sandruzzo]

Originally Posted by Amiten

Hi, Rygar is one of my fav arcade game for sure, many coins of 25 pesetas I spend back in the time. Nice thread but there are some one making this game for Amiga?? In case yes ,wich lenguaje?? ASM ? C? Basic? Thanks

Just programming it with asm

[sandruzzo]

Scroll routine Almost in place,just some adjustment here and there.. Any Gfx Tiles and map?