engineRequestModel("vehicle") doesn't load default GTA scripts

[Xenius97]

Describe the bug
engineRequestModel("vehicle") doesn't load default GTA scripts
I've tested with Towtruck, Tractor, Police Maverick (light doesn't work), Seasparrow (can't fire), Packer etc.

To reproduce
engineRequestModel("vehicle", 525)

Version
Multi Theft Auto v1.5.8-release-20732

[AlexTMjugador]

#1701 explicitly states that this kind of behaviours do not work:

Does not work:

• Сhassis
• Turrets
• ZR-350 opening headlights
• Rhino, Hydra, Skimmer, Seasparrow
• Some specific effects like a dust effect from some helicopters, smoke effects from bikes.
• Another hardcoded stuff

I guess this is caused because somewhere in GTA code they are limited to a specific vehicle ID. If that's the case, for these to work, the affected methods would need to be patched.

[qaisjp]

The wiki should be updated to include this information. That article is also missing correct versioning usage

[Xenius97]

Trains doesn't work too.

[Fernando-A-Rocha]

🤔 Is it possible to fix this at this stage?

[Pirulax]

Would require to patch tons of code, so no, not really.
Special features are hard coded based on modelID.

[TheNormalnij]

I think it's still hackable. When i added vehicle allocation i thought about a setVehicleModelFeatureState function

[lopezloo]

I think it could be implemented like that:

mtasa-blue/Client/multiplayer_sa/CMultiplayerSA.cpp

Lines 5755 to 5794 in eedbdc5

	// Check if this vehicle is allowed to process swinging doors.
	static DWORD dwSwingingDoorAutomobile;
	static const DWORD dwSwingingRet1 = 0x6A9DB6;
	static const DWORD dwSwingingRet2 = 0x6AA1DA;
	static bool AllowSwingingDoors()
	{
	SClientEntity<CVehicleSA>* pVehicleClientEntity = pGameInterface->GetPools()->GetVehicle((DWORD*)dwSwingingDoorAutomobile);
	CVehicle* pVehicle = pVehicleClientEntity ? pVehicleClientEntity->pEntity : nullptr;
	if (pVehicle == 0 || pVehicle->AreSwingingDoorsAllowed())
	return true;
	else
	return false;
	}
	void _declspec(naked) HOOK_CAutomobile__ProcessSwingingDoor()
	{
	_asm
	{
	mov dwSwingingDoorAutomobile, esi
	mov ecx, [esi+eax*4+0x648]
	pushad
	}
	if (AllowSwingingDoors())
	{
	_asm
	{
	popad
	jmp dwSwingingRet1
	}
	}
	else
	{
	_asm
	{
	popad
	jmp dwSwingingRet2
	}
	}
	}

Hooking in place of these ID checks and calling vehicle entity method to check if specific feature is enabled for specific vehicle element.

So MTA API might look like this:

setVehicleFeatureEnabled(vehicle theVehicle, string feature, bool enabled)

In some places there might be no vehicle entity available though in theory. It would be great to document all the missing features.

[Fernando-A-Rocha]

Bumping this. A lot of people have messaged me in regards to my resource newmodels saying that added vehicles can't have features like attaching trailers, having water hose etc... It's a popular demand