天行健 君子当自强而不息

Controlling Players and Characters(26)

 

Taking a Swing

When a character takes a swing at another character, this action triggers the
process that determines whether the blow hit the target. Determining whether the
attack hit involves an attacking character’s to-hit ability and a defending character’s
agility ability. Remember that the higher the ability values, the better the chance to
hit or dodge the attack.

The to-hit ability can range from 0 (always misses) to 999 (always hits). By taking
a random number and comparing it to the to-hit value, you can quickly determine
whether a hit was accomplished. If the random number is equal to or less than the
to-hit attribute, the blow lands. The following code illustrates how to determine
whether a hit is successful:

// ToHit = character’s to-hit attribute value
long RandomValue = rand() % 1000;
BOOL HitFlag = (RandomValue <= ToHit) ? TRUE : FALSE;

In the preceding code, HitFlag is set to TRUE if the blow lands, or rather if the blow
should land. In order to improve the chances of hitting a target, the attacker can
have specific status ailments that decrease or increase the to-hit value. Two status
ailments in use that affect the attacker’s to-hit ability are Blind and Hawkeye. The
Blind status ailment reduces the to-hit chance ability by 25 percent, whereas
Hawkeye increases the chances to hit by 50 percent.

To apply either status ailment modifiers, multiply the determined to-hit value:

if(Ailments & AILMENT_BLIND)
  ToHit = (long)((float)ToHit * 0.75f);

if(Ailments & AILMENT_HAWKEYE)
  ToHit = (long)((float)ToHit * 1.5f);

long RandomValue = rand() % 999;
BOOL HitFlag = (RandomValue <= ToHit) ? TRUE : FALSE;

 

Dodging an Attack

Remember that a victim’s agility ability comes into play when being attacked. The
greater the defender’s agility, the greater the chance the victim dodges the attack.
You calculate whether the defender dodges the attack in the same way that you
check whether the attacker makes a hit:

// Agility = character’s agility ability
RandomValue = rand() % 999;
BOOL DodgeFlag = (RandomValue <= Agility) ? TRUE : FALSE;

In order to decrease or increase the chances of dodging an attack, you
can use the Clumsy and Surefooted status ailments. Clumsy decreases
the chances of dodging and attack by 25 percent, whereas Surefooted
increases the chances by 50 percent (meaning that characters that are
affected by both the Clumsy and Surefooted ailments have their
chances of dodging an attack increased by 25%):

CAUTION
You can determine from the agility dodging calculations that the higher the
agility, the higher the chance of dodging the attack. For that reason, you generally
don’t set a character’s agility too high because they can become untouchable.

if(Ailments & AILMENT_CLUMSY)
  Agility = (long)((float)Agility * 0.75f);

if(Ailments & AILMENT_SUREFOOTED)
  Agility = (long)((float)Agility * 1.5f);

long RandomValue = rand() % 999;
BOOL DodgeFlag = (RandomValue <= Agility) ? TRUE : FALSE;

 

Dealing Damage

When it is determined that the blow hit the victim, it’s time to calculate how much
damage was done, which is where the character’s attack and defense abilities come
into play. Damage is usually variable, which means that rarely does the same attack
do the same damage each time. Again, you use a little randomness.

To keep things simple, you can take the attacker’s attack ability value (or at least 90
percent to 110 percent of it) and subtract the victim’s defense value (at least 80
percent to 100 percent of it). Note that status ailments are an issue here as well,
along with the use of items to increase the attack and defense abilities.

That’s right. Equipped items add a multiplier to the attack and defense abilities.
The item modifier value is the key. The value represents a value from 0 and up
that, when divided by 100 and increased by one, gives you a multiplier value to use
in conjunction with the ability value. For example, a weapon with a modifier value
of 150 increases the attack ability by 50 percent:

// Attack = character’s attack ability value
// Item[] = master item list array
long Attack = (long)((float)Attack * (((float)Item[Weapon].Value / 100.0f) + 1.0f));

Getting back to status ailments, two affect both attack and defense—Weak and Strong.
Weak reduces attack and defense by half whereas Strong increases the values by 50 percent.
Here’s how everything works to determine the amount of damage to apply:

// Attack = attacker’s attack ability value
// Defense = defenders defense ability value
// Item[] = master item list array
// Weapon = weapon # in item list (or -1 if none)
// Armor = armor # in item list (or -1 if none)
// Shield = shield # in item list (or -1 if none)
// Determine attack amount
// Start with adding equipping weapon modifier

if(Weapon != -1)
  long Attack = (long)((float)Attack * (((float)Item[Weapon].Value / 100.0f) + 1.0f));

// Adjust by status ailments
if(Ailments & AILMENT_WEAK)
  Attack = (long)((float)Attack * 0.5f);

if(Ailments & AILMENT_STRONG)
  Attack = (long)((float)Attack * 1.5f);

// Determine defense amount
// Apply armor and shield modifiers
if(Armor != -1)
  Defense = (long)((float)Defense * (((float)Item[Armor].Value / 100.0f) + 1.0f);

if(Shield != -1)
  Defense = (long)((float)Defense * (((float)Item[Shield].Value / 100.0f) + 1.0f);

// Apply status ailments
if(Ailments & AILMENT_WEAK)
  Defense = (long)((float)Defense * 0.5f);

if(Ailments & AILMENT_STRONG)
  Defense = (long)((float)Defense * 1.5f);

float DamagePercent = ((float)(rand() % 70) + 50.0f) / 100.0f;
long DamageAmount = (long)((float)Attack * DamagePercent);

// Determine damage amount (use some randomness in there)
float Range = (float)((rand() % 20) + 90) / 100.0f;
long DmgAmount = (long)((float)Attack * Range);
Range = (float)((rand() % 20) + 80) / 100.0f;
DmgAmount -= (long)((float)Defense * Range);

At long last, the DmgAmount variable will contain the amount of damage that is dealt.
You’re not done at this point, however, because now character class comes into
play. If an attack is strong against the character’s class type, damage is doubled.
If the victim is of the same class as the attack, that attack cures the
victim for half the amount of damage dealt! I’ll let you work those into the calculations.

CAUTION
Again, the defense ability of a character shouldn’t be so high that the defending
character rarely takes any damage when an attack hits.

posted on 2007-12-03 20:31 lovedday 阅读(258) 评论(0)  编辑 收藏 引用


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