adjust the tohit formula

[tiancaiamao]

The current tohit formula is not good enough:

server/src/server/gameserver/skill/HitRoll.cpp

Lines 146 to 178 in 3c2054f

	if (ToHit >= Defense)
	{
	// 투힛이 디펜스보다 높은 경우에는 맞출 확률이 꽤...높다.
	#ifdef __CHINA_SERVER__
	Result = min(90, (int)(((ToHit - Defense) / 1.5) + 60) + ToHitBonus);
	#else
	if ( isMonster )
	{
	Result = min(95, (int)(((ToHit - Defense) / 3) + 50) + ToHitBonus/2);
	}
	else
	{
	Result = min(90, (int)(((ToHit - Defense) / 3) + 50) + ToHitBonus/2);
	}
	#endif
	}
	else
	{
	// 투힛이 디펜스보다 낮은 경우에는 맞출 확률이 많이 떨어진다.
	#ifdef __CHINA_SERVER__
	if( isMonster ) {
	Result = max(10, (int)(60 - ((Defense - ToHit) / 1.5) + ToHitBonus));
	} else {
	Result = max(20, (int)(60 - ((Defense - ToHit) / 1.5) + ToHitBonus));
	}
	#else
	if( isMonster ) {
	Result = max(5, (int)(50 - ((Defense - ToHit) / 3) + ToHitBonus/2));
	} else {
	Result = max(10, (int)(50 - ((Defense - ToHit) / 3) + ToHitBonus/2));
	}
	#endif
	}

I think this one is better:

tohit ratio = 0.5 + (tohit - defense) / [(tohit + defense) * k + C]

k=0.1
C=120