Patch framework for C3C v1.22

[Antal1987]

Last week I created a thread, describing an idea of making of patch framework for C3C. And now I'm glad to introduce my first release of this patch framework.

Patch framework_v1

I also published framework sources to github ...
with a bonus: Civ3Conquests.h. That huge (6K lines) header contains all data types I could determine and recognize. Some of them will be described in details soon.

First patch I impelemented in the Framework is the Science Age Patch (see thread)

Origin patch was placed in PE-header alignment space.

CPU Disasm
Address   Hex dump          Command                                    Comments
00400200      83EC 04       SUB ESP,4
00400203      C704E4 000080 MOV DWORD PTR SS:[ESP],3F800000
0040020A      D905 5C906600 FLD DWORD PTR DS:[Science_Age_Ratio]       ; FLOAT 3.000000
00400210      D824E4        FSUB DWORD PTR SS:[ESP]
00400213      D91CE4        FSTP DWORD PTR SS:[ESP]
00400216      DB44E4 0C     FILD DWORD PTR SS:[ESP+0C]
0040021A      D80CE4        FMUL DWORD PTR SS:[ESP]
0040021D      83C4 04       ADD ESP,4
00400220      E8 4F9F2400   CALL __ftol
00400225      89C7          MOV EDI,EAX
00400227      0186 F8000000 ADD DWORD PTR DS:[ESI+0F8],EAX
0040022D      E9 19201600   JMP 0056224B

And the call code was:

CPU Disasm
Address   Hex dump          Command                                    Comments
00562228  |. /74 21         JE SHORT 0056224B
0056222A  |. |8B15 6C26A500 MOV EDX,DWORD PTR DS:[Current_Turn]
00562230  |. |8B86 D4150000 MOV EAX,DWORD PTR DS:[ESI+15D4]            ; _this->Science_Age_End
00562236  |. |3BD0          CMP EDX,EAX
00562238  |. |7F 11         JG SHORT 0056224B
0056223A    ^|E9 C1DFE9FF   JMP 00400200
0056223F     |90            NOP
00562240     |90            NOP
00562241     |90            NOP
00562242     |90            NOP
00562243     |90            NOP
00562244     |90            NOP                                        ; _Total_Bulbs = (_Total_Bulbs * 1.25);
00562245     |90            NOP
00562246     |90            NOP
00562247     |90            NOP
00562248     |90            NOP
00562249     |90            NOP                                        ; _Total_Bulbs = (_Total_Bulbs * 1.25);
0056224A     |90            NOP
0056224B  |> \85FF          TEST EDI,EDI

Now, I encapsulated patch code into the patch framework. Here is how it looks like:

int CPatchFramework::CorrectScienceAgeBulbs(class_Leader * Civ, int Total_Bulbs)
{
	float * p_Science_Age_Ratio = (float *)0x0066905C;
	int D_Bulbs = (int)((float)Total_Bulbs * (*p_Science_Age_Ratio - 1.00));
	Civ->Research_Bulbs += D_Bulbs;
	return Civ->Research_Bulbs;
}

Convenient, huh?

And the call is now:

CPU Disasm
Address   Hex dump          Command                                    Comments
00562238  |. /7F 11         JG SHORT 0056224B                                 Comments
0056223A      56            PUSH ESI
0056223B      57            PUSH EDI
0056223C      56            PUSH ESI
0056223D      A1 74967300   MOV EAX,DWORD PTR DS:[C3CPF_Object]
00562242      8B00          MOV EAX,DWORD PTR DS:[EAX]
00562244      FF50 08       CALL DWORD PTR DS:[EAX+8]          ; call CPatchFramework::CorrectScienceAgeBulbs        
00562247      89C7          MOV EDI,EAX
00562249      5E            POP ESI                                    
0056224A     |90            NOP
0056224B  |> \85FF          TEST EDI,EDI

So now any complex patch can be easily written inside patch framework using predefined data structures and then it just should be called in proper place.

 

[Steph]

Sounds very good. I'll have to look closely at your header file when I have more free time.
By the way, if you can manage to have more options to the game, and need a way to save it, I could make a new version of my editor for that.
For example, if you want to add a new flag for units "bonus against fast moving unit", and manage to have it taken into account in the battle resolution (to have pikemen with bonus vs cavalry), we could make a version 2.0 of the biq and save files.
I can take care of the editor part, if you can add it to the load/save function of the main game.

And I see you have still a few unknown items in your structure.

Like for units

int Air_Missions;
int field_B8;
int Bombard_Fix;

I can check with my documentation of the format if I can help you fill the gaps (hoping the data structure comes in the same order as in the save format).

 

[Antal1987]

I can check with my documentation of the format if I can help you fill the gaps (hoping the data structure comes in the same order as in the save format).

It doesn't actually. When I start investigating game memory I used this: Civilization-III-BIX-BIQ-file-format

But then I realized, that reading and writing functions in game data structures don't save fields' order. It even doesn't always save flags storage format.

And I see you have still a few unknown items in your structure.

I have a lot of unknown items in my structures, because while reading the game expands saved data to wides structures, and it stores there some other data (Animations data, for instance)

 

[Steph]

Gramphos documentation dates 2004. I stopped working on my editor 4 years later, so maybe I have more fields identified.
I'll have a look at your structures and my doc this week-end, I have some free time, and see if I can help you to decipher more.
I also have some unknown fields which seems to have no apparent effects though, let's see if we have the same holes.

 

[Puppeteer]

Awesome! Thanks!

 

[Moosezilla]

I (and the world) awaken to a new era.

 

[Antal1987]

I'll have a look at your structures and my doc this week-end, I have some free time, and see if I can help you to decipher more.
I also have some unknown fields which seems to have no apparent effects though, let's see if we have the same holes.

I've designed some tools to calculate values/flags distributions of any list/array items. These tools are part of a trainer program I'm developring now. It works, but it's not so stable/perfect to publish. I'm just using it to research unresearched or even unresearchable... and to play a little.

Along with OllyDbg and IDA it helps me to understand how does the game renders it's data, where does it store one and many other things.

If you're interested, I could share it to you.

 

[Steph]

I am very interested, but unfortunately I don't have much time. So don't tempt me too much!