MESS : What kind of cheats to add ?

[stephh]

Since MESS 0.138, MESS is able to handle softwarelists ... This means that you can launch for the SMS either :

Code: Select all

mess sms -cart "roms\sms\ace of aces (europe).bin"

or

Code: Select all

mess sms -cart aceoface

provided you have "ace of aces (europe).bin" and aceoface.zip in roms\sms (or another folder for rompath= in mess.ini).

In a future release (hopefully MESS 0.141u2), there will be such a list for the Coleco, and you shall be allowed to have multiple XML files in cheats\coleco (one for each game supported by the list).

Now the question is the following : do we have to find "RAM" cheats (eg: force number of lives somewhere in memory) or do we have to find "ROM" cheats (eg: change the instruction that decrements numbre of lives to "NOP" or something like that) ? I would vote for the first one because this is what we try to do most of the time in MAME, but I wanted to be sure ...

Note that such lists will also be handle in MAME 0.141u2 for some systems (eg: MegaTech hardware), so it might be interesting to know what to do for these games ...

Steph from The Ultimate Patchers

[Pugsy]

Support for softwarelist cheats has only recently been added though (not tried them myself yet). I'm a little concerned that the softwarelists will get updated/changed around a lot so deadbeef.xml will always be correct but gamename.xml may change.

It's really upto the one making the cheat files, in most instances I'd imagine it's going to be RAM (or location) cheats. With ROM (or Program Code) cheats used for stuff like Collision Invincibility.

If there is ever a C64 cheat file and I'm involved it will probably be Program Code cheats rather than location cheats.

'Megatech' makes 0.141u2 sound an even bigger update then....looks like I'll have to do 0.142 release with those and the multitude of mechanical games added recently (which now all have reason comments), was going to leave it for a few months .

[etabeta78]

Support for softwarelist cheats has only recently been added though (not tried them myself yet). I'm a little concerned that the softwarelists will get updated/changed around a lot so deadbeef.xml will always be correct but gamename.xml may change.

hopefully not that much. the problem is that, as you said, lists are still very recent: we added in a single shot lists for nes, snes, gb, gbc, gba, gen, sms & gg. sorting out parent/clone and reasonable names requires some time (especially with those sega games which got ~15-20 protos released by drx).
anyway, at this stage nes/snes/gen/sms/gg should be more or less established, and I would expect the filename to change more or less as often as those in MAME.

gameboy lists are currently under work to get on par with the others.

after that, I would expect more Description changes (-> no effect on the cheats) than setname changes


also notice that deadbeef.xml is not 100% reliable since we have console dumps using split roms like mame (see e.g. NES) and therefore you don't have a single crc to use

It's really upto the one making the cheat files, in most instances I'd imagine it's going to be RAM (or location) cheats. With ROM (or Program Code) cheats used for stuff like Collision Invincibility.

If there is ever a C64 cheat file and I'm involved it will probably be Program Code cheats rather than location cheats.

ROM cheats would allow for importing things like GameGenie/PAR codes, but this would also mean a lot of fake codes in some cases (depending on the sources)

'Megatech' makes 0.141u2 sound an even bigger update then....looks like I'll have to do 0.142 release with those and the multitude of mechanical games added recently (which now all have reason comments), was going to leave it for a few months .

well, the megatech games will be listed with their MAME name and therefore MAME should successfully take the cheats from the mt_xxxx.xml file... I'm not sure how well they will behave when you try to load 8 carts, though

Since MESS 0.138, MESS is able to handle softwarelists ... This means that you can launch for the SMS either :

Code: Select all

mess sms -cart "roms\sms\ace of aces (europe).bin"

or

Code: Select all

mess sms -cart aceoface

provided you have "ace of aces (europe).bin" and aceoface.zip in roms\sms (or another folder for rompath= in mess.ini).

just a minor remark on these usage notes: if you load from softlists (a' la MAME) the aceoface.zip *MUST* be in _rompath_\sms.
but if you load by using the location of the file, then you can put the gamefile wherever you want: e.g.

Code: Select all

mess sms -cart "C:\my\favorite\path\aceoface.zip"

would work as well like a charm

[NotAGoodName]

So quick question.

Will this eventually mean that I can eventually have one XML cheat file that applies to more than one Sega Genesis game without it applying to all of them? I don't really like the CRC system, and having one colossal file to work with becomes daunting rather quickly.

[stephh]

So quick question.

Will this eventually mean that I can eventually have one XML cheat file that applies to more than one Sega Genesis game without it applying to all of them? I don't really like the CRC system, and having one colossal file to work with becomes daunting rather quickly.

It will be the same as it is in MAME : one XML file for each game (even if there are clones) ...

If there is a software list (hash/.xml file), it will look for the .xml file based on the shortname of the game ...

If there is no software list (only a hash/.hsi file), it will look for the .xml file file based on the CRC ...

And according to the code in MAME 0.141u2, the cheat engine is able to load multiple cheat files if there are multiple devices (eg multiple MegaTech cartridges) ...

Steph from The Ultimate Patchers

[etabeta78]

And according to the code in MAME 0.141u2, the cheat engine is able to load multiple cheat files if there are multiple devices (eg multiple MegaTech cartridges) ...

this is something absolutely necessary in MESS, because e.g. for pc engine you need to use the -cart name for HuCard games, but the -cdrom name for PCE-CD games!
given that to run CD games you also need to mount a CD-system cart in the cartslot, in this case you end up with 2 devices used and you cannot assume in the cheat system that a single device is going to be necessary.

as you see even simple 8bit consoles can give this kind of problems, but of course home computers can make things a lot worse.

it is the same kind of problem which has affected MESS with snap naming until a month ago: snaps were bound to system.png (e.g. pce.png, nes.png, etc.) because there was no way to assume any priority among the various devices.
for snaps the problem has been solved through "snapname" templates (like MAME were already doing with %g and %i), but for cheats I think it is smart to simply look for xmls named after each mounted device. it might also help for wip cheats because it allows e.g. to put some pce-cd cheats inside a unique cdsys.xml (cdsys is the name of the CD cart which all CD games require) and to have them loaded for all the CD games you load in the -cdrom...

Of course, some small adjustment for displaying them properly might be needed, but I will look into it once Aaron is done with his romload.c changes (same goes for the path issue you reported )

[stephh]

And according to the code in MAME 0.141u2, the cheat engine is able to load multiple cheat files if there are multiple devices (eg multiple MegaTech cartridges) ...

this is something absolutely necessary in MESS, because e.g. for pc engine you need to use the -cart name for HuCard games, but the -cdrom name for PCE-CD games!
given that to run CD games you also need to mount a CD-system cart in the cartslot, in this case you end up with 2 devices used and you cannot assume in the cheat system that a single device is going to be necessary.

I didn't say it was bad to look for each device : it is indeed a very good thing to look at everything

as you see even simple 8bit consoles can give this kind of problems, but of course home computers can make things a lot worse.

The problem with computer is that we may never have "proper dumps" of floppies, thus no software list

it is the same kind of problem which has affected MESS with snap naming until a month ago: snaps were bound to system.png (e.g. pce.png, nes.png, etc.) because there was no way to assume any priority among the various devices.
for snaps the problem has been solved through "snapname" templates (like MAME were already doing with %g and %i), but for cheats I think it is smart to simply look for xmls named after each mounted device. it might also help for wip cheats because it allows e.g. to put some pce-cd cheats inside a unique cdsys.xml (cdsys is the name of the CD cart which all CD games require) and to have them loaded for all the CD games you load in the -cdrom...

I haven't looked at the snaps stuff yet, but I don't see where the problem is here : if you have something like "mess pce -cdrom cdsys", it will of course look for cheats in cdsys.xml (even if I still think that it should look in fact in pce\cdsys.xml) ...

Of course, some small adjustment for displaying them properly might be needed, but I will look into it once Aaron is done with his romload.c changes (same goes for the path issue you reported )

IMO, display doesn't need to be changed, especially when in each xml file you have a "fake" cheat with the name of the game : even if they are now based on CRC, donwload the Coleco database ( http://www.mediafire.com/file/jqygik2zy ... CO_0134.7z ) and see what I mean ...

Steph from The Ultimate Patchers

[etabeta78]

The problem with computer is that we may never have "proper dumps" of floppies, thus no software list

well, tools like KryoFlux will help for sure. and in the meanwhile one can create a list with the best possible dumps to at least document what software existed (at a later stage, better dumps can replace the older ones, when available)

I haven't looked at the snaps stuff yet, but I don't see where the problem is here [...]

yup, luckily there is no problem for cheats. I just mentioned snaps because it was another example of situation where you have to scan all the devices to avoid unexpected bad effects

MO, display doesn't need to be changed, especially when in each xml file you have a "fake" cheat with the name of the game

I hadn't thought about this simple trick! smart move.