/// <summary>
/// Combines wandering and separation
/// </summary>
public static void Wander(IAgent agent, IAgent[] otherAgents, ref Steering.SteerParameters steerParams)
{
// add up the steering forces
Vector3 wander = Steering.WanderForce(agent, ref steerParams);
Vector3 separation = Vector3.Zero;
Vector3 bounds = Steering.WorldBoundsForce(agent, steerParams);
int avoiding = 0;
for (int i = 0; i < otherAgents.Length; i++)
{
IAgent otherAgent = otherAgents[i];
if (agent != otherAgent)
{
float separationDistance = Vector3.Distance(agent.Position, otherAgent.Position);
if (separationDistance < steerParams.SeparationRange)
{
separation += Steering.SeparationForce(agent, otherAgent, steerParams, separationDistance);
avoiding++;
}
}
}
agent.Direction = Vector3.Normalize(agent.Direction + wander + separation + bounds);
}
/// <summary>
/// Combines wandering, cohesion, separation, and alignment steering such that the agent moves
/// together with other members in the flock
/// </summary>
public static void Flock(IAgent agent, IAgent[] flockMembers, ref Steering.SteerParameters steerParams)
{
Vector3 wander = Steering.WanderForce(agent, ref steerParams);
Vector3 separation = Vector3.Zero;
Vector3 cohesion = Vector3.Zero;
Vector3 alignment = Vector3.Zero;
Vector3 worldForce = Steering.WorldBoundsForce(agent, steerParams);
Vector3 goalForce = Steering.GoalForce(agent, steerParams);
int alignmentWith = 0;
int cohesionWith = 0;
for (int i = 0; i < flockMembers.Length; i++)
{
IAgent otherAgent = flockMembers[i];
if (agent != otherAgent)
{
float separationDistance = Vector3.Distance(agent.Position, otherAgent.Position);
if (separationDistance < steerParams.SeparationRange)
separation += Steering.SeparationForce(agent, otherAgent, steerParams, separationDistance);
else
{
cohesion += Steering.CohesionForce(agent, otherAgent, steerParams);
cohesionWith++;
float scale = MathHelper.Clamp(1 - separationDistance / steerParams.AlignmentRange, 0, 1);
if (scale > 0)
{
alignment += Steering.AlignmentForce(otherAgent, steerParams) * scale;
alignmentWith++;
}
}
}
}
if (cohesionWith > 1)
cohesion /= cohesionWith;
if (alignmentWith > 1)
alignment /= alignmentWith;
agent.Direction = Vector3.Normalize(agent.Direction + wander + separation + cohesion + alignment + worldForce + goalForce);
}
public void SetSteeringParameters(Steering.SteerParameters steerParams)
{
this.steerParams = steerParams;
}
public void ApplySteerParameters(Steering.SteerParameters steerParams)
{
foreach (Bird b in birdFlock.Agents)
b.SetSteeringParameters(steerParams);
}
