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ctfknife_isbehindandfacingtarget.cpp

// reverse engineered from TF2 ServerLinux 20151007a by sigsegv

bool CTFKnife::IsBehindAndFacingTarget(CTFPlayer *pVictim)
{
	CTFPlayer *pSpy = ToTFPlayer(this->GetPlayerOwner());
	if (pSpy == nullptr) return false;
	
	Vector2D wsc_spy_to_victim = (pVictim->WorldSpaceCenter() - pSpy->WorldSpaceCenter()).AsVector2D();
	wsc_spy_to_victim.NormalizeInPlace();
	
	Vector temp1; pSpy->EyeVectors(&temp1);
	Vector2D eye_spy = temp1.AsVector2D();
	eye_spy.NormalizeInPlace();
	
	Vector temp2; pVictim->EyeVectors(&temp2);
	Vector2D eye_victim = temp2.AsVector2D();
	eye_victim.NormalizeInPlace();
	
	if (DotProduct2D(wsc_spy_to_victim, eye_victim) <=  0.0f) return false;
	if (DotProduct2D(wsc_spy_to_victim, eye_spy)    <=  0.5f) return false;
	if (DotProduct2D(eye_spy,           eye_victim) <= -0.3f) return false;
	
	return true;
}