Engine W2S

lea  edx, [esp+80h+var_60]
push edx
lea  eax, [esp+84h+var_6C]
push eax
mov  eax, [esp+88h+arg_0]
lea  edx, [esp+88h+var_54]
call sub_42D6D0
add  esp, 8

char __usercall sub_42D6D0<al>(int a1<eax>, int edx0<edx>, int a2, int a3)

void w2s(float * x, float * y, Vec3 vPoint )
{
	DWORD dwCall = 0x42D6D0;
	__asm{
		PUSH y
		PUSH x
		MOV EAX, 0x0
		MOV EDX, vPoint
		CALL [dwCall]
		ADD ESP,0x8
	}
}

void w2s(Vec3 vPoint, float * x, float * y)
{
	DWORD dwCall = 0x43E900;
	__asm{
		push y
		push x
		mov eax, vPoint
		mov ecx, 0x0
		call [dwCall]
		add esp, 0x8
	}

}

class w2s_t
{
public:
	char unknown[108];
};

w2s_t * w2scalc = (w2s_t*)0x108B658;
void w2s(Vec3 vPoint, float screen[2])
{
	DWORD dwCall = 0x416290;	
	__asm {
		push screen
	 	push vPoint
	 	push w2scalc
		push 0x0
	 	call [dwCall]
	 	add esp, 0x10	
	}
}

bool __cdecl sub_4913C0(int CalcIndex, Vec3 Point, float vOut[2])

usage : 

float vOut[2];
if(w2s(0, entity->vorigin, vOut)) 
{
	DrawText(vOut[0], vOut[1], "text");
}