This might have been asked before, but anyone here thought about releasing a IPS patch to Metal Gear using the Snake graphics Konami used in the Metal Gear 'classic' they released together with Snake Eater in PS2?

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That's EXACTLY why I was asking! I had the same problem. It could be some kind of text pointer issue... I tried to contact the creator of the patch, but his e-mail account doesn't exist anymore. Do you think you could fix it having a deeper look??

I will have a deeper look. But I suspect that part of the compressed text is damaged. Do you have a previous version of this patch? I just need to know what text is printing after credits. And I know for the fact that the text is different from Metal Gear EU version.

Max

but the old graphics are much better

Of course, it is a matter of taste, but in the original MG2, Snake seems to be a middle age guy, while in the Playstation he seems younger. I think the young look is better, but maybe it is just me.

Would it be possible to also include the other features of the recent re-release such as the new menu, the boss battle mode and the new bandana item?

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Would it be possible to also include the other features of the recent re-release such as the new menu, the boss battle mode and the new bandana item?

I think not unless someone lwho is a programmer like Nyyrikki does the job which includes adding graphics,menus and stuff to a 22 year old rom,99% filled with no free space in it.To me it seems impossible.

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Quote: Would it be possible to also include the other features of the recent re-release such as the new menu, the boss battle mode and the new bandana item? I think not unless someone lwho is a programmer like Nyyrikki does the job which includes adding graphics,menus and stuff to a 22 year old rom,99% filled with no free space in it.To me it seems impossible.

Rom space doesn't seem to be a problem, since you can always increase the size of the rom (using 768kb or 1024kb). The (only) major issue is to find someone willing to do this task.

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Quote: Quote: Would it be possible to also include the other features of the recent re-release such as the new menu, the boss battle mode and the new bandana item? I think not unless someone lwho is a programmer like Nyyrikki does the job which includes adding graphics,menus and stuff to a 22 year old rom,99% filled with no free space in it.To me it seems impossible. Rom space doesn't seem to be a problem, since you can always increase the size of the rom (using 768kb or 1024kb). The (only) major issue is to find someone willing to do this task.

Those konami games have something different.The whole game main loop is inside the interrupt handler,they did this in order to always have a vdp syncro no matter if it is pal or ntsc.However i still don't think it would be easy to add stuff like that to games.The whole interrupt handler would have to be changed ,and since the main game loop is in that handler i doubt it can happen

the fact that the interrupt handler controls the game shouldn't make any difference if the question is to replace graphics (without enhancing them in a way that costs more cpu power to be drawn) or add new game options that won't have impact after the game starts. It will only affect if you want to have more things happening at the same time during the game, because you can run out of cycles and miss a interrupt.

That said, we all know it is not easy to disassembly a binary code of a game and change it to add new stuff, but it is possible, since it has been done before (by skilled people). In this case, I believe the hardest part will not be changing the game, but finding someone willing to do this task.

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the fact that the interrupt handler controls the game shouldn't make any difference if the question is to replace graphics (without enhancing them in a way that costs more cpu power to be drawn) or add new game options that won't have impact after the game starts. It will only affect if you want to have more things happening at the same time during the game, because you can run out of cycles and miss a interrupt. That said, we all know it is not easy to disassembly a binary code of a game and change it to add new stuff, but it is possible, since it has been done before (by skilled people). In this case, I believe the hardest part will not be changing the game, but finding someone willing to do this task.

Adding the item will be hard.The easy thing would be to replace one of the items.It is not hard.I have dissasembled part of the metal gear rom and found some places where there are items and how you can change them to anything you like.(i mean the gfx)
The tough part is adding gameplay functionality that was not part of the game.The whole game is inside the main loop of the interrupt handler.

In theory we should need more space (at least 8kbytes i think),and to find some space inside the interrupt handler where the new code lies that adds the new functionality.With a few calls outside the interrupt handler in theory that could happen.
Problem now is that konami uses an 8kbyte memory mapper.So the code executed lies into that space of 8kbytes each time.

Those games were in very compact form i think.8bkytes at the time for the code.

In theory we can select an item change each appearnce (by editing the gfx that are in compressed form in the video ram).However we want extra functionality from that object.That requires to change the whole interrupt handler.Since each object or item has some default things that does to the game following the programmers code.

Example you select the mine detector,you can see the mines after the game codes goes to a subroutine that displays those hidden objects.
Now the difficult thing is to find the space inside the mapper 8kbyte that konami has and add the functionality you want and integrate it with the original game code.I think that would require many subroutines and extensive calls and jumps to happen.

The first thing we can do in theory is find the code that does the screen initilization and has the push any key to start.By dissasembling the original code in theory you could change the default behavior and add a menu item.Problem is that the new code that does that must lie in the original code location.In theory you could place some code outside the main loop that could do that stuff.And return to the original jump point.

What i did in the past is disable part of the game code.Example i nopped some instructions and made the cameras not move.I nopped some other instructions and the cameras and soldiers would not show at all on screen.I disabled some other instructions and i could move the sprite of the character anywhere on screen (and make the game crash when i went to some place i was not supposed to go).

Nopping those instructions is easy,replacing them with different code is the difficult stuff.Because that would require whole new asm subroutines to do the stuff.

If you want i can post some of those subroutines and what they do.Someone more experianced could in theory replace them with something new.

Hi Nikodr,

thanks for explaining what it takes to make changes to the original metal gear code. Indeed, when you want to add new things that will change the gameplay, things can get really complex, and may not be possible at all. That's why I'm satisfied with a simple graphic hack, they are usually easier to do and in most of the cases they are feasible.

btw, merry christmas to all.