Dune-hacking - the rom-hacking of Dune: The Battle for Arrakis (Sega Genesis)

[topos84]

A friend of mine is finishing making an editor for this game now. He's using GameMaker and the program is already works, but there are some bugs and interface problems, which, I hope, will be solved in a few months (maybe earlier).

With this program you can change lots of things in the game. You can change landscape (put mountains, dunes, spice and other elements of landscape wherever you want), add units and structures, change AI and armor of units which are already on the map, change armor of structures which are already on the map, edit the landings, starport entries etc.

So with this program you can make your own hack of Dune: The Battle for Arrakis and play it on an emulator (which is not illegal, if you have a cartridge of this game, I believe).

Guys, I really want to know your opinion about this matter.

P.S. Sorry for my English.

[Nyerguds]

Sounds awesome :)

[topos84]

I forgot to tell about changing and adding houses in a certain mission. You can change any house in a mission to another one, even to Sardukars/Imperor, Fremen and Mercenary, but Fremen and Mercenary are kinda buggy, especially Mercenary.

[MrFlibble]

I forgot to tell about changing and adding houses in a certain mission. You can change any house in a mission to another one, even to Sardukars/Imperor, Fremen and Mercenary, but Fremen and Mercenary are kinda buggy, especially Mercenary.

So basically you can make a version of Super Dune 2 for Sega? Cool ;D

[topos84]

So basically you can make a version of Super Dune 2 for Sega? Cool ;D

Well, not exactly. You can't play for Sardukars or Fremens without the cheat code (the game genie code), and even with it you can't play properly (especially for Fremens). For Mercenary you can't play at all, 'course there's no game genie code for that. But you can play against these houses, even against all of them in a same mission (actually you can play against all the houses except yours in a same mission, but there are structure limit and unit limit, so you can't make a normal mission in this case). And, as I said before, there some bugs when you play against Fremens or Mercenary. In case of Fremens they are barely noticeable: little round radars on each structure can have red colour at first, but then it can change to blue color and between these to colour phases there can be a middle phase of colour, which is pretty funny, isn't it? :)

In case of Mercenary there's a red colour of these radars, but that's not the problem. The problem is this house have no colour of its units and structures on the minimap! There are just holes in it (you can say they have the color of a transparency). That seems pretty weird when you play against Mercenary.

I hope these bugs will be eliminated in a future.

[MrFlibble]

It is interesting that they kept the Mercenaries in the Sega version as well, although this side is never used in the game. Or are the Saboteurs owned by the Mercenaries in the Sega version? (I think it's possible that the the Saboteur was originally planned as not directly controllable by the player, just like the Fremen, and the Mercenaries were to be the side that controlled Saboteurs)

[topos84]

It is interesting that they kept the Mercenaries in the Sega version as well, although this side is never used in the game. Or are the Saboteurs owned by the Mercenaries in the Sega version? (I think it's possible that the the Saboteur was originally planned as not directly controllable by the player, just like the Fremen, and the Mercenaries were to be the side that controlled Saboteurs)

You are totally right. Sabuteurs owned by the Mercenaries in the Sega version, though he has his colour on the minimap (light-purple). BTW, worms and Fremens are in the same house in the Sega version, that's why worms don't eat fremens (even their tanks and harvesters if you do those in the editor).

[MrFlibble]

BTW, worms and Fremens are in the same house in the Sega version, that's why worms don't eat fremens (even their tanks and harvesters if you do those in the editor).

Same in the PC version, although the Sandworms there will attack Fremen too, unless they are put on in the Area Guard mode.

[MrFlibble]

Will it be possible to edit unit/building stats? It is also a curious fact that the Saboteur in the Sega version has seemingly kept his 500-hp damage explosion attack, although most structures have twice as much hit points compared to their PC counterparts, effectively limiting the list of buildings a Saboteur can destroy in a single blow.

[topos84]

Will it be possible to edit unit/building stats?

It is possible now. But you can edit only those units' (buildings') stats, which will be in the mission from the beginning (those which you put somewhere while you were editing this mission), not those which will be built by you in that mission.

[Nyerguds]

That's bizarre... why would it keep a full set of stats for the units that will be placed on the map? Normally it should just load the default unit object for each one and only adapt the health to the mission setting...

[topos84]

Normally it should just load the default unit object for each one and only adapt the health to the mission setting...

You mean there should be an opportunity to change the default HP of all kinds of units and buildings of certain mission in the editor? I don't think it's possible, but I'll ask my friend about this stuff.

[Nyerguds]

well in C&C mission ini files, there's a percentage (actually, part of 256) setting for every unit and structure placed on the map. I think the same exists in the Dune inis too...

[MrFlibble]

You mean there should be an opportunity to change the default HP of all kinds of units and buildings of certain mission in the editor? I don't think it's possible, but I'll ask my friend about this stuff.

Actually I was asking about modifying the global stats that do not change from mission to mission. I don't think it was possible to modify unit type stats (that would affect both the pre-placed units of that type and whatever new units that were produced during the mission) for a specific scenario until Red Alert.

[topos84]

Actually I was asking about modifying the global stats that do not change from mission to mission. I don't think it was possible to modify unit type stats (that would affect both the pre-placed units of that type and whatever new units that were produced during the mission) for a specific scenario until Red Alert.

For now it's impossible to change the global stats of units and buildings with the editor, because the editor doesn't edit the rom-file, it does edit a pieces of rom-file, those pieces, which it makes by splitting the rom-file into 'object-files' (mission-files) and 'level-files' (map-files), then it edits these pieces (you can even edit only map-file or only mission-file with the editor), saves the changes into these pieces and builds a new rom-file from these pieces.

Maybe later, when the rom-file will be more deciphered (decrypted), there will be such modifying of global stats of units and buildings.

[MrFlibble]

those pieces, which it makes by splitting the rom-file into 'object-files' (mission-files) and 'level-files' (map-files), then it edits these pieces (you can even edit only map-file or only mission-file with the editor)

So in the Sega version, there are separate files for the terrain map used in each mission, right? This is interesting, because in the PC version, terrain is generated from a so-called "seed" value.

[Nyerguds]

It's also interesting because it's a step towards C&C1, just like the context-sensitive mouse cursor.

[topos84]

So in the Sega version, there are separate files for the terrain map used in each mission, right? This is interesting, because in the PC version, terrain is generated from a so-called "seed" value.

Well, in Sega games there are no such things as 'files'. There are just roms. The rom is an image of game cartrige, which is like HDD drive but without file system. But you can find in a rom infomation of certain types: music, sound semples, graphics. Other information in rom-file is very difficult to recognize, because it is mostly commands to CPU to do some manipulations with other information in rom-file.

I think, there are the segments of code in the rom-file, consist of commands to CPU to generate the terrain map of each mission, but I really don't think, that there are segments of the code, consist of whole terrain maps for each mission (Sega have only 64KB of RAM so it seems to be the problem to put the whole map into RAM before the mission starts and keep it there). But I'm not sure. I'll ask my friend about it.

[Nyerguds]

You talk about maps as if they're full images. They aren't. They're usually just one byte for each cell on the map, defining the terrain type of that cell. The different types of cell graphics are loaded elsewhere, and just drawn on screen according to the map information.

[topos84]

You talk about maps as if they're full images. They aren't. They're usually just one byte for each cell on the map, defining the terrain type of that cell. The different types of cell graphics are loaded elsewhere, and just drawn on screen according to the map information.

That's right. But somehow the information of all map cells of each mission was ripped from the rom-file. I think there can be sort of table of pointers for each mission, each of them points to certain graphic cell, stored in the rom, and this table can be loaded to RAM at the beginning of mission. That's why the map of each mission could be ripped from the rom with this editor, I suppose.

[MrFlibble]

Can you tell more about the mission format? In the PC version, the missions (SCEN#???.INI) are just plain text. I think it's different in the Sega version, but is it possible to get info, for example, on triggers that handle air-dropped reinforcements?

[topos84]

Actually, I know nothing about mission format, nither in Sega version, nor in PC version. But I can ask one of my friends - Ti_ (he is great rom-hacker and, I hope, will help Segaman (the author of Dune Map Editor) soon) about air-dropped reinforcements, if you give the link to download one of files SCEN#???.INI (maybe Ti_ will find it out by comparing info from the rom-file and from SCEN#???.INI file).

[MrFlibble]

maybe Ti_ will find it out by comparing info from the rom-file and from SCEN#???.INI file

I remember looking into the Dune ROM myself, and I think there's nothing like the PC version scenario format, which is basically plain text. For example, reinforcement triggers look like this:

[pre][REINFORCEMENTS]

1=Ordos,Troopers,Enemybase,12

2=Ordos,Quad,Enemybase,12

3=Ordos,Troopers,Enemybase,12[/pre]Curiously, the REGION#.INI files that contain controls for the conquest map and corresponding text that is displayed are still in the ROM, even though there is no map selection or display of newly conquered territories in the Sega version.

[topos84]

In the rom:

0A05 = reinforsments(ID) , (house).w , (unitype).w , (base/home).w , (timer in min).b , (2B).b  ; 2B if repeat

For example,

0A05 0002 0006 0006 022B = landing#ID5 , house atreides , rocketlauncher  , home, every 2min

0A05 0002 0006 0006 0200 = same thing, but only one time

[MrFlibble]

Cool, thanks :) I think that repeated reinforcements are used more frequently in the Sega version than in the PC version (not to mention that repeated reinforcements do not work by default in the PC version in the first place :D). I've got that feeling that the gameplay is more fast-paced in the Sega version, which is partially due to different reinforcement scripts.

BTW, you can take a look at the PC version scenario files in the Dune 2 Scenario Pack, which is attached here. The reinforcement scripts that were supposed to be repeated have a plus sign at the end (these are in missions 4, 8 and 9 only).