Retrieving graphics from AvsP

[Mutantant]

Hey all.

 

So, the main games that keep me holding on to Ye Olde Jaguar, even as some games have aged very poorly, are the classics like AvsP and Tempest 2k. One day, I thought to myself something many of us have thought in the past: We need a port/remake of AvsP. Frankly, as flawed as the game is (think, super-low frame rate) it honestly is an amazing, complex, hard, it-doesn't-hold-your-hand classic game.

 

Well, as an avid Doom modder, I realized by using one of the modern Doom ports like ZDoom and GZDoom, which include very advanced scripting capabilities, one could possibly make something like a remake of AvsP. Not exact, for sure, as they are not the same engine, but something like it. For those in doubt, google Brutal Doom and watch a video or two, as every aspect of Doom has been changed, enhanced, scripted, and GORYfied to the extent the game is like new: Faster paced, harder, and certainly more violent and tactical.

 

This leads me to the question of graphics. Now, there are decent enough Aliens mods for Doom out there I can crib graphics from. But the best thing would be to use the original graphics. You see where this is going?

 

Now, my understanding is the Jag:

1. Used no "sprites" in the way other systems did, as in having special sprites that one could easily pull from a cart.
2. Compressed all its graphics with BPEG.

JagViewer nets me nothing from AvsP (p.s. I own 75% of the Jaguar library, including AvsP, so there is no moral conundrum here poking at a ROM). I can kind of see a bit of the title screen, maybe, but the rest is garbage.

 

The questions:

1. Has anyone used JagViewer to see the sprites and graphics of AvsP (likely not, as JagViewer is for uncompressed images)
2. Is there a utility to go through a rom and decompress things? The whole rom? Just the graphics?
3. Does anyone know of any already ripped AvsP graphics?
4. In the end, what's your opinion on it anyway. If the speed, damage, weapons, and maps are converted enough to make the game *feel* like AvsP, but the graphics are different, would it still tickle the need?

An example of the Doom based AvsP style graphics I would use if I cannot get the real stuff:

[4ever2600]

That would be awesome. I wish I knew more about the Jag to be able to help you but unfortunately that isn't the case. I have however played most of the Alien style mods for Doom Doom 2 Quake Duke Nukem etc. There is alot of source material out there...

[+save2600]

First time I ever saw someone abbreviate AvP as AvsP!

 

(Great idea btw - would love a faster paced Alien/Predator Doom-like game)

[Mutantant]

First time I ever saw someone abbreviate AvP as AvsP!

 

(Great idea btw - would love a faster paced Alien/Predator Doom-like game)

Ooh, I do love being first!

[Mutantant]

My idea was to keep the good and ditch the bad. Speed up the gameplay a little, as much of the slow gameplay was actually a function of frame rate rather than actual design. But not have it KILL KILL KILL Doom paced speed either. Keep the map design and basic elements, the 3 modes of play, all of that, but also be rid of the bit where all enemies repopulate after a save, because that was due to save ram limitations rather than design.

 

That's not to say enemies won't repopulate over time... Just it will be a controlled respawn to keep tension and danger up but not cheaply destroy all your ammo reserves due to everything coming back at once...I hated that.

[sh3-rg]

I had a quick look and got nowhere. GGN took a look, informed me the gfx were likely jagpeg as he browsed the code and stuff

 

I noticed one file, obviously outdated as it is targeting a 2mb ROM, but maybe it is somewhat informative and might give you some hints.

                           ==============================


    Description:                                            Memory (k for kbytes NOT kbits):

    ------------                                            --------------------------------

Jaguar statup code                                                 8k



65 wall panels at 32k each with 6.5:1 JPEG compression (we have tried this now on a lot and            320k

of panels and get very good results at up to this ratio or slightly higher). There are more

than 65 panels because all the signs (armoury, medlab etc.) are saved as one base panel plus

overlays, but the artists have accepted the equivalent size of 65 panels to work within.

The true value will probably around 70 as not that many panels benefit from these overlays.



Animations and objects in maze: these are stored in the same format, and a further complication

is that they can be run direct from ROM if required. In fact there is not enough room in RAM to

have all these items in RAM so we store some uncompressed in ROM and some compressed and then

moved into RAM. Uncompressed there are 747k of animations and 150k of maze objects. The compression

ratio from simple LZW compression (i.e. we can get it done sooner rather than later) is 1.5:1.

There is 600k of RAM free for this data therefore we have:



600k of compressed anims:                                            400k

300k of uncompressed anims:                                            300k



Mission screens: 3 full screens at 320x240 pixels CRY, with 4:1 compression using JPEG (generated

scenes do not compress as well as scanned scenes)                                115k



Computer screens and overlays: the equivalent of 6 full screens' worth (i.e. 3 screens plus overlays)

in 256 colours using LZW compression i.e. 6x320x240x2/3                                307k



Intro and game completion screens: 2 320x240 generated screens                             77k



Sound: see attached comments from Chris                                        256k



Explosions                                                     80k



Gun overlays                                                     80k



Code                                                         64k



HUD overlays                                                     30k



                                                     -----

Total:                                                     2037k





                            RAM Allocation

                            ==============



Expaned panels (max. of 32 different 32k panels per level)                         1024k



RAM buffers: 2 320x240 screens and all other buffers as currently used by game system (i.e. clipping

buffer, GPU code overlays, current HUD weapon overlays, object lists, JPEG decompression tables)        424k



Uncompressed anims in RAM (see above)                                        600k



                                                     -----

                                                     2048k

GGN reckoned running in emulator/RAM dumping/ripping might be a plan. Have to dash, maybe GGN chips in later.

[Lost Dragon]

For myself an ideal remake would include:

The shotgun design from the Beta version of AVP (Jag)...

Implement the Predator/Aliens actually attacking each other at random stages in the game (no scripted events mind).

Adress the issue of the acid puzzles-maybe have areas eaten away by acid, rather than puddles being left on the ground?.

Improve the mapping system....

Speed up the cocooning process when playing as the Xeno.

Keep the atmospheric, slow pace compared to Doom etc.

[Mutantant]

I had a quick look and got nowhere. GGN took a look, informed me the gfx were likely jagpeg as he browsed the code and stuff

 

I noticed one file, obviously outdated as it is targeting a 2mb ROM, but maybe it is somewhat informative and might give you some hints. ...**removed code to shorten reply** GGN reckoned running in emulator/RAM dumping/ripping might be a plan. Have to dash, maybe GGN chips in later.

 

Nice document, thanks. Using the ram dump idea, I loaded t2k_0.06c and loaded the game. t2k_0.06c does poorly with AvP, won't run the marine campaign at all, marines won't fire on you as an alien, and the marine sprites are screwed, BUT it does allow for a save-state ram dump. Using that dump and JagView I managed to get some textures and sprites, but the colors are all wrong no matter what mode I set. Don't know if it is a JagView bug or a palate thing. VJ doesn't seem to allow ram dumping and when using HxD to dump the ram of the whole program I wasn't able to get any decent results.

 

The document you copied here seems to state the graphics get loaded in and out of RAM a lot as well, so that could be a problem.

 

However, it also gives me a number of textures: 65 (plus a few extra for signs) which means VJ + screenshots + Photoshop = getting all the textures. This would suck, of course...

 

 

 

For myself an ideal remake would include:

The shotgun design from the Beta version of AVP (Jag)...

Implement the Predator/Aliens actually attacking each other at random stages in the game (no scripted events mind).

Adress the issue of the acid puzzles-maybe have areas eaten away by acid, rather than puddles being left on the ground?.

Improve the mapping system....

Speed up the cocooning process when playing as the Xeno.

Keep the atmospheric, slow pace compared to Doom etc.

 

 

I agree with most of that and will keep it in mind.

Shotgun design, maybe, as the beta has no animations for me to use.

Acid puzzles, certainly, as I think that's poor game design in a game with such limited health. Needs to disappear sooner or later, somehow. Or you need to get boots, or have the ability to jump.

Mapping system would be ZDoom standard, i.e. better than Doom, and Doom was better than AvP as it was.

Cacooning, maybe a bit faster.

Game speed, AvP * 1.5 - in other words, way slower than Doom, but faster than AvP, as AvP was slow only due to frame rate. To see what I mean, load AvP in VJ and turn on faster blitter. Plays so smooth, and a bit faster, but still slow and methodical.

Edited November 26, 2015 by Mutantant

[Lost Dragon]

The remake is sounding bloody great already and it's fantastic to hear from someone who really understands why AVP was a flawed gem of a showcase game.

 

I personally think you need to keep the acidic blood, as it's yet another element that makes the Xeno stand out from your average FPS grunt/cannon fodder.. ( and any plans to make the Xeno's more agressive, A.I wise? ) but it needs to fade away over time...

 

I was considering asking about more weapon mods..ie underslung grenade launcher, but i wonder if that'd tamper with the gameplay too much?

 

If you make the Marine too powerful, you loose a lot of the fear....

[NeoGeoNinja]

The remake is sounding bloody great already and it's fantastic to hear from someone who really understands why AVP was a flawed gem of a showcase game.

 

I see this a lot from many a Jag fan.

 

AVP was really ever flawed as such. At the time, off the back of playing Super Street Fighter II on my SNES and Gunstar Heroes on my Mega Drive, specifically as a console-only gamer, AVP was a massive leap in every respect.

 

It's only 20 years later, as the genre has moved on, AVP - in terms of gameplay etc, just hasn't aged as well as some of its contemporaries (Doom, DN3D etc).

 

It was unreal back in the day.

[Mutantant]

Hey all, OP here to quickly make something super clear before the thread turns into a back and forth AvP comparison thing...

AvP is flawed. So was Fallout, Baulder's Gate, Myst, etc. All games have flaws. Even the greats. That's why game patches exist, something I think AvP would have had if it was a PC game now rather than a hard coded permanent cart in 93.

I think AvP is a good enough game to spend my very limited free time working on a remake of, so have little doubt I think it's a truly amazing game in every respect. It was at the time. It is today.

But some things are flaws. Gameplay flaws (unavoidable acid on the ground in a game where health kits are sparse, halls at thin, ammo limited, and enemies plentiful). Flaws caused by system limitations (frame rate hindered by Atari's odd limitations on what programmers were allowed to do with each of the multiple processors in the Jag, super gimpy save ram space on carts leading to every enemy respawning on load since there wasn't enough space to save much more than ammo count and location).

As I think about a remake, I must also think about the strengths and weaknesses of the game. It's only natural to list some of those out.

But these do not reflect on the game as a whole. The Jag was a hard system to code. Atari was a harsh taskmaster. Time was tight. The game was literally the best it could be at the time.

I do not, however, think it's a bad idea to remix some of the limitations into strengths as the game is being rebuilt from scratch.

No one needs to defend the honor of the game. It's a great game. One of the best ever.

Hence why I want to play it again, this time in higher resolution, with better saves, and a few tweaks

 

P.s. this is not a direct reply to NeoGeoNinja, so please don't take it as such. NeoGeoNinja is responding to a long history of hearing this or that complaint, many unfounded, and it's all cool that they dropped a message here. I just want to head off a reply->angry reply->defense->more reply dark message board spiral of thread death

Edited November 27, 2015 by Mutantant

[PlaysWithWolves]

I had a quick look and got nowhere. GGN took a look, informed me the gfx were likely jagpeg as he browsed the code and stuff

 

 

Yep, he's right! 16-bit JagPEG, according to an interview in GamePro #59, pp.20-21 (full mag. can be downloaded here in CBR format):

 

 

[Lost Dragon]

The vast majority of the AVP Games i've played on far more powerful hardware than the Jaguar were also flawed:

Alien Trilogy on PS1 had terrible Xeno A.I-They just were nowhere near aggressive enough to be considered a real threat.

Alien Res. PS1-You really needed the PS Mouse to play it, as it was awful playing via standard controller.

AVP 2 PC (Monolith) lacked the superb Xeno A.I routines from Rebellions earlier PC AVP and whilst looking very pretty, was a weaker AVP game...

As for Rebellions PSP AVP and later AVP game on PC/PS3/360... games were dumbed down beypnd all measure...

Alien Isolation PS3:Went on far too long, hated the scripted A.I parts...

Considering i'm a massive Aliens fan, it's natural i'm going to love what has been done, but also think if only they had done this with the game.....

Which is why i'm loving the idea of Jaguar AVP being 'fixed' in several places.

[Lost Dragon]

Rebellion talking to RG Magazine about development issues of AVP:

[The game] took longer than anticipated, but remember the budget was halved right at the start, and the tech was incomplete as were lots of the tools we had to use. We put a lot of time and effort into compressing the game into a 2Mb cartridge, and then about a month from completion the cartridge size was doubled to 4Mb. We could’ve saved a lot of time and effort if we’d had that cartridge size decided earlier on.

We had a programmer come in to help on the project for, as it turned out, about 3 months, but he actually made things go backwards and we had to rip his code out in the end and completely rewrite that part from scratch.

It is always a technical challenge working on a new console, but we’ve faced this many times and we thrive on these sorts of challenges. You have to work with changing hardware specs, incomplete documentation and buggy or incomplete compilers.

[ggn]

VJ doesn't seem to allow ram dumping and when using HxD to dump the ram of the whole program I wasn't able to get any decent results.

I'm pretty sure you have to launch vj with -alpine switch to enable ram dumping but I can't really remember which key to press. I'm sure shamus would be able to comment on this

 

The document you copied here seems to state the graphics get loaded in and out of RAM a lot as well, so that could be a problem.

 

However, it also gives me a number of textures: 65 (plus a few extra for signs) which means VJ + screenshots + Photoshop = getting all the textures. This would suck, of course...

Well, the document also states that the assets are LZW packed but I couldn't find any distinct headers in the ROM. Probably the best course of action would be to dump the ROM into something like Ida Pro, map out some sections, find and rip the packer, find the game's "file system" and chop and feed the files to the depacker. I might give this a shot over the weekend.

[Atlantis]

I think AvP is a good enough game to spend my very limited free time working on a remake of, so have little doubt I think it's a truly amazing game in every respect. It was at the time. It is today.

 

As I think about a remake, I must also think about the strengths and weaknesses of the game. It's only natural to list some of those out.

Wonder why no one is bashing your head for writing this... well, guess universe works in mysterious ways...

 

1. Are you coding this, 2. is there a chance of a 100% release, now when you know it's working out well (?) and it WILL come on CD or cart within a couple of years??

 

Sorry if I do bring in dark forces, my questions are very honest.

Edited November 27, 2015 by Atlantis

[Mutantant]

Wonder why no one is bashing your head for writing this... well, guess universe works in mysterious ways...

 

1. Are you coding this, 2. is there a chance of a 100% release, now when you know it's working out well (?) and it WILL come on CD or cart within a couple of years??

 

Sorry if I do bring in dark forces, my questions are very honest.

Thanks for asking, these are all valid questions with a simple answer. This is not a Jaguar coding project but rather a port or conversion of one of the best Jag games on to another system and engine.

 

The engine in question is ZDoom. It is a Doom source port that has been updated monthly almost from the very release of the Doom source code to today. It adds a trillion things, not the least of which is 3D architecture, full mouse look, OpenGL, scriptable enemy behavior, full full full modding capability. Like full. At this point it acts as a perfect engine for any 2.5D FPS game you could want. People have used it to create things nothing at all like Doom.

 

I am an experienced Doom modder, and ZDoom modder, and in the end the engines are more similar than different, early 1990s 2.5D shooter with similar texture resolutions, monster Sprite sizes, etc.

 

The goal: Recreate the experience of AvP using ZDoom, which is an engine that runs on PC, Mac, Android systems, and others. Recreate the tension, puzzle maze craziness, the struggle for ammo and health. Do so with original graphics if I can, or existing AvP style graphics if I cannot. Using ZDoom's advanced enemy AI scripting abilities (Google ZDoom ACS), recreate the enemies, not as reskinned imps and demons, but as Aliens and Predators. And while doing so, iron out a few annoying gameplay elements in a way that doesn't ruin the balance, i.e., if a grenade launcher is added to the pulse rifle, make ammo rare and explosions so wide and deadly that it makes it skill based to use without killing yourself in a tight hallway. Finally, to do this quickly, as the Internet is filled with languishing half finished projects.

 

As far as 100% guarantee to finish it...well if I say yes, then you know I'm lying, as this is how it works on the net. So, I leave this at "I really think so, and have most of it already planned in my head, and years of experience to back it up, but God knows I could be killed by a freak bus falling out of the sky at any moment so who knows" level.

[Lost Dragon]

Rebellion were planning (with upgrade version from Jaguar to PS1+Saturn) to allow the player to look Up/Down as well as Left/Right...

No idea IF ZDoom lets you do this, but if so, would you consider adding this ability? or would you rather stay true to the Jaguar original?.

Hopefully not a stupid Q, but as i said, no idea what features are on offer in ZDoom and i've always seen the canned PS1/Saturn game as the next stage between Jaguar AVP and Rebellions Windows'95 PC AVP....

[Mutantant]

 

Rebellion were planning (with upgrade version from Jaguar to PS1+Saturn) to allow the player to look Up/Down as well as Left/Right...

 

No idea IF ZDoom lets you do this, but if so, would you consider adding this ability? or would you rather stay true to the Jaguar original?.

 

Hopefully not a stupid Q, but as i said, no idea what features are on offer in ZDoom and i've always seen the canned PS1/Saturn game as the next stage between Jaguar AVP and Rebellions Windows'95 PC AVP....

Not a dumb question at all. ZDoom (the software only version of ZDoom) allows skewed Duke Nukem type mouselook. GZDoom, the OpenGL ZDoom, allows full 3D mouse look. Both also allow jumping. These can be limited and disabled by me as I see fit developing the mod.

 

Of course, the vanilla AvP maps are all on a 2D plane, with no real reason to look up or down.

 

But, aliens do so love the ceiling...and I already have the code to make certain aliens pop out of the ceiling (vents and the like) if it seems like something that would be cool. Looking up and down would be very handy then.

[ggn]

Ok, roughly 30 mins into this - here's what I got:

 

- The compression algorithm used is zip inflate

- Based on that I had a quick peek at the depacker and found a header pattern $1F8B0800C8C16F2E0205

- Searching for that pattern inside the rom I also found "GZIP" there before each file - d'oh, if I only noticed that from the start!

- A quick extract of files beginning with that pattern and feeding them to gunzip, it gave me 110 files. A lot of them are equally sized so there's a good chance they're textures and game pictures!

- Didn't check what the files contain!

 

 

So I'm done for now - next!

avp.rar

[Sporadic]

Rock star

[Mutantant]

Ok, roughly 30 mins into this - here's what I got:

 

- The compression algorithm used is zip inflate

- Based on that I had a quick peek at the depacker and found a header pattern $1F8B0800C8C16F2E0205

- Searching for that pattern inside the rom I also found "GZIP" there before each file - d'oh, if I only noticed that from the start!

- A quick extract of files beginning with that pattern and feeding them to gunzip, it gave me 110 files. A lot of them are equally sized so there's a good chance they're textures and game pictures!

- Didn't check what the files contain!

 

 

So I'm done for now - next!

Pimp dude, pimp! You need to pick that mic up so you can drop it again and again. I'll take a gander as soon as I get home.

 

And this is why I came to AA forum-to tap into the power of hex wielding rom fiends to find something I was unable to!

[Atlantis]

Thanks for asking, these are all valid questions with a simple answer. This is not a Jaguar coding project but rather a port or conversion of one of the best Jag games on to another system and engine.

That explains the non-bashing issue, and both of my questions. Thx.

[Mutantant]

That explains the non-bashing issue, and both of my questions. Thx.

Yeah, I'm not mad enough to delve into Jag development with what free time I have. No sir. Though I'm sure ZDoom could be compiled for the Jag and the mod could end up on a cart that way. But not I, not I.

[Lost Dragon]

@Mutantant:Thanks for understanding my ignorance on ZDoom.I had it with a PC Cover disk, back when i dabbled for a while in PC Gaming (mainly for the AVP Games, ironically enough), but never used it.

I'm loving your comment here:

'But, aliens do so love the ceiling...and I already have the code to make certain aliens pop out of the ceiling (vents and the like) if it seems like something that would be cool. Looking up and down would be very handy then. '

That would add so much to the tension and the feel of the whole dealing with a mere man Vs Xenomorph experience...

You have to 'get inside' it's head to have a chance of fighting it, it's not going to just run right at you....

As Ridley Scoot once said regarding future Alien Films: ' You've got to change the beast'.