[SA] CLEO. Is it possible to get rope length for heli (Leviathan) ? [SOLVED]

[vladvo]

I tried everything, but I failed. As far as I understand - the rope from Leviathan to magnet is not an 'object'. Still, in IDA there is this code:
 

006D3D10
.text:006D3D10                             ; =============== S U B R O U T I N E =======================================
.text:006D3D10
.text:006D3D10
.text:006D3D10                             ; double __thiscall CVehicle::GetRopeHeightForHeli(void *this)
.text:006D3D10                             _ZN8CVehicle20GetRopeHeightForHeliEv proc near
.text:006D3D10 000 83 C1 1D                                add     ecx, 1Dh
.text:006D3D13 000 51                                      push    ecx             ; id
.text:006D3D14 004 E8 E7 22 E8 FF                          call    _ZN6CRopes8FindRopeEj ; CRopes::FindRope(uint)
.text:006D3D19 004 69 C0 28 03 00 00                       imul    eax, 328h
.text:006D3D1F 004 83 C4 04                                add     esp, 4
.text:006D3D22 000 D9 80 D4 6B B7 00                       fld     _ZN6CRopes6aRopesE.m_dwHeight[eax] ; CRopes::aRopes
.text:006D3D28 000 C3                                      retn
.text:006D3D28                             _ZN8CVehicle20GetRopeHeightForHeliEv endp

Judging by presence if ___thiscall - the right opcode to use is 0AA8.  I tried  passing everything - heli handle, heli struct, magnet handle, magnet struct. Nothing. Screws camera. 
When I hover cursor over *this it shows xref to CCam::Process_1rstPersonPedOnPC(CVector const&,float,float,float)+54. 
I am totally confused. I guess the rope is a graphical 'something', but it is still handled by the game. Is it possible to get the rope lenght ?
And the most important part of the question - is there a really good guide on how to use 0AAx opcodes and call functions ?

Edited 4 hours ago by vladvo

[Jack]

@vladvo

I got the same result. When I use this function in the other language it works fine. In scm it just freezes like you described. 
Now on the rope lenght issue:
Although we got the opcode 0796 which assumes we already have magnet handle (which is btw not $Crane_Magnet) and even if we do we also need to check if it'a attached to a vehicle. 
To do all that we need to use CRope class. 

The magnet object used by #LEVIATHN heli is defined as 3053 - INDUS_MAGNET so lets define what we have so far:

Spoiler

const
    INDUS_MAGNET = 3053
    CRopeStruct = 0x556AE2  //  example pointer to  _ZN6CRopes6aRopesE 
end

Now, the game has a limit of 8 ropes (0 - 7) used at once. Each rope object is 0x328 size and it starts at:

0xB768B8    //  _ZN6CRopes6aRopesE

so the iteration loop might come in handy:

for [email protected] = 0 to 7 step 1
    
end

Any of these 8 ropes can be used for the magnet so lets start checking which is it. So first lets check if there's a rope attached to an entity:

Spoiler

for [email protected] = 0 to 7 step 1  
    0085: [email protected] = [email protected]
    0AB1: cleo_call @readMemoryOffsetWithIterr params 3 stuct CRopeStruct offset 0x310 iteration [email protected] result_to [email protected] //  CEntity *m_pRopeHolder; 
    if [email protected] <> 0
    then
        //  there's an entity attached at one or more ropes
    end
end
:readMemoryOffsetWithIterr
//  [email protected] CRopeStruct; [email protected] offset; [email protected] iteration
[email protected] *= 0x328 //  CRope struc size
0A8D: [email protected] = read_memory [email protected] size 4 virtual_protect 0
005A: [email protected] += [email protected]
005A: [email protected] += [email protected]
0A8D: [email protected] = read_memory [email protected] size 4 virtual_protect 0
0AB2: cleo_return 1 [email protected]

Now lets check if that rope has our magnet:

Spoiler

for [email protected] = 0 to 7 step 1  
    0085: [email protected] = [email protected]
    0AB1: cleo_call @readMemoryOffsetWithIterr params 3 stuct CRopeStruct offset 0x310 iteration [email protected] result_to [email protected] //  CEntity *m_pRopeHolder;   
    0085: [email protected] = [email protected]
    0AB1: cleo_call @readMemoryOffsetWithIterr params 3 stuct CRopeStruct offset 0x314 iteration [email protected] result_to [email protected] //  CObject *m_pRopeAttachObject;
    if and
        [email protected] <> 0
        [email protected] <> 0 
    then
        [email protected] += 0x22
        0A8D: [email protected] = read_memory [email protected] size 2 virtual_protect 0  //  CEntity *m_nModelIndex;
        [email protected] += 0x22
        0A8D: [email protected] = read_memory [email protected] size 2 virtual_protect 0  //  CEntity *m_nModelIndex;
        if and 
            [email protected] == #LEVIATHN
            [email protected] == INDUS_MAGNET
        then 
            //  there're two entities attached to a rope
            //  a heli with the ID 417 and the magnet of ID 3053 
        end   
    end
end
:readMemoryOffsetWithIterr
//  [email protected] CRopeStruct; [email protected] offset; [email protected] iteration
[email protected] *= 0x328 //  CRope struc size
0A8D: [email protected] = read_memory [email protected] size 4 virtual_protect 0
005A: [email protected] += [email protected]
005A: [email protected] += [email protected]
0A8D: [email protected] = read_memory [email protected] size 4 virtual_protect 0
0AB2: cleo_return 1 [email protected]

and now we can check its lenght:

Spoiler

const
    INDUS_MAGNET = 3053
    CRopeStruct = 0x556AE2  //  pointer to  _ZN6CRopes6aRopesE 
end

while true
    wait 0
    for [email protected] = 0 to 7 step 1  
        0085: [email protected] = [email protected]
        0AB1: cleo_call @readMemoryOffsetWithIterr params 3 stuct CRopeStruct offset 0x310 iteration [email protected] result_to [email protected] //  CEntity *m_pRopeHolder;   
        0085: [email protected] = [email protected]
        0AB1: cleo_call @readMemoryOffsetWithIterr params 3 stuct CRopeStruct offset 0x314 iteration [email protected] result_to [email protected] //  CObject *m_pRopeAttachObject;
        if and
            [email protected] <> 0
            [email protected] <> 0 
        then
            [email protected] += 0x22
            0A8D: [email protected] = read_memory [email protected] size 2 virtual_protect 0  //  CEntity *m_nModelIndex;
            [email protected] += 0x22
            0A8D: [email protected] = read_memory [email protected] size 2 virtual_protect 0  //  CEntity *m_nModelIndex;
            if and 
                [email protected] == #LEVIATHN
                [email protected] == INDUS_MAGNET
            then         
                0085: [email protected] = [email protected]
                0AB1: cleo_call @readMemoryOffsetWithIterr params 3 stuct CRopeStruct offset 0x31C iteration [email protected] result_to [email protected] //  float m_fRopeSegmentLength;
                
                0087: [email protected] = [email protected]
                [email protected] *= 10.0
                0092: [email protected] = float_to_integer [email protected]
                03F0: enable_text_draw 1
                045A: text_draw_1number  50.0  100.0 'NUMBER' [email protected]
                    
                //  8 - 0     where 8 is the shortest rope value which is odd
            end
        end
    end
end 
:readMemoryOffsetWithIterr  
//  [email protected] CRopeStruct; [email protected] offset; [email protected] iteration
[email protected] *= 0x328 //  CRope struc size
0A8D: [email protected] = read_memory [email protected] size 4 virtual_protect 0
005A: [email protected] += [email protected]
005A: [email protected] += [email protected]
0A8D: [email protected] = read_memory [email protected] size 4 virtual_protect 0
0AB2: cleo_return 1 [email protected]

Although in c++ this whole thing can be done in a single line:

float ropeHeight = playa->m_pVehicle->GetRopeHeightForHeli();

It could probably be done within the scm as well with the fnc you provided - I just don't know how.

 

EDIT: @Wesser I was wondering what that opcode is doing. I wish you're here more often. 

Edited Tuesday at 04:12 PM by Jack

[Wesser]

You are supposed to pass a CVehicle pointer and then pop a floating-point value from the stack using POP_FLOAT (2793) command.

[ArmanCan]

@vladvo i have a tiny info which you may adapt or use as a reference.. i found this global variable in Sanny Builder's help folder "CustomVariables.ini" .. it maybe useful for you 

 

10496=Crane_Rope_Length

 

[vladvo]

4 hours ago, ArmanCan said:

10496=Crane_Rope_Length

Thanks, but a crane is a crane. This var works only for crane.

[vladvo]

On 4/4/2023 at 6:38 PM, Wesser said:

You are supposed to pass a CVehicle pointer and then pop a floating-point value from the stack using POP_FLOAT (2793) command.

Thank you !
 

0A97: [email protected] = vehicle [email protected] struct
0AA6: call_method 0x6D3D10 struct [email protected] num_params 0 pop 0
0AE9: pop_float [email protected]

Odd thing is that when the magnet is at highest (closest to heli) position - it shows  0.84. When the rope is fully extended (longest) - it shows 0.01. Anyways - it works. That's almost enough. Time to figure out how to set rope lenght. )
Update. Setting the rope:

 

[email protected] = 0.01
0AA6: call_method 0x6D3D30 struct [email protected] num_params 1 pop 0 [email protected] //006D3D30 ; int __thiscall CVehicle::SetRopeHeightForHeli(void *this, float)

About the lenght - 0.84 is 'usual' magnet appearance at takeoff (slightly extacted rope). If it is set to 0.99 it is right below the heli. 

Edited 3 hours ago by vladvo
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