Simple AI test

[dejai]

I was wondering if this was any good for a simple following AI, I am yet to learn about cast line

not complete code

Code: Select all

while (device->run())
{
vector3df playerpos = player_node->getPosition();
vector3df enemypos = enemy_node->getPosition();
vector3df encounter = playerpos - enemypos;

if (encounter <= 50 || encounter >= -50)
{
// Goto Player Attack 
}
}

Just asking is the concept of the code correct, I am almost sure that I have done something wrong and I may have to do something more like this.

Code: Select all

vector3df playerpos = player_node->getPosition();
vector3df enemypos = enemy_node->getPosition();
vector3df encounter = playerpos - enemypos;
vector3df distance;
distance.X = 50;
distance.Y = 50; 
distance.Z = 50;

if (encounter <=distance  || encounter >= -distance)
{
// Goto Player Attack 
}

}

[/code]

[rogerborg]

Try to generalise your problems. At this stage, AI is a red herring. The general problem is that you want to know how to calculate how far apart two scene nodes are.

That means (thiiiiink) that you want to know the length of the vector between the two nodes, right? So...

Code: Select all

vector3df playerpos = player_node->getPosition();
vector3df enemypos = enemy_node->getPosition();
vector3df difference = playerpos - enemypos;

f32 distance = difference.getLength();

or, using a handy little vector3d method, just this:

Code: Select all

f32 distance = player_node->getPosition().getDistanceFrom(enemy_node->getPosition());

Note that both getLength() and getDistanceFrom() perform a sqrt() calculation, which is relatively computationally expensive. It's more efficient to do getLengthSQ() or getDistanceFromSQ(), and then compare the result to the (pre-calculated) square of the attack distance.

Code: Select all

enum
{
    ATTACK_DISTANCE = 50,
    ATTACK_DISTANCE_SQUARED = 50 * 50
};

// Not very efficient
f32 distance = player_node->getPosition().getDistanceFrom(enemy_node->getPosition())

if(distance < ATTACK_DISTANCE)
{
    // attack
} 

// More efficient
f32 distanceSQ = player_node->getPosition().getDistanceFromSQ(enemy_node->getPosition())

if(distanceSQ < ATTACK_DISTANCE_SQUARED)
{
    // attack
} 

[MasterGod]

Smart ..