private void RefreshPath(NodeNetwork nodeNetwork, PositionedObject target, TileShapeCollection solidCollisions, TileShapeCollection pitCollision)
{
var ai = InputDevice as TopDown.TopDownAiInput <Enemy>;
// We are going to pathfind to a location
// that is not exactly on the target but on
// a point on a line perpendicular to the enemy.
// This is a quicky way to add some randomness and
// spread out the enemies so they come from different directions
var pathfindingTarget = target.Position;
var lineToTarget = target.Position - this.Position;
var perpendicular = new Vector3(-lineToTarget.Y, lineToTarget.X, 0);
if (perpendicular.Length() != 0)
{
perpendicular.Normalize();
var distanceFromTarget = lineToTarget.Length();
const float distanceToPerpendicularLengthRatio = 1 / 2f;
pathfindingTarget = target.Position + perpendicular * perpendicularLengthRatio * distanceToPerpendicularLengthRatio * distanceFromTarget;
}
if (DebuggingVariables.ShowEnemyAiShapes)
{
thisToPerpendicularTarget.SetFromAbsoluteEndpoints(this.Position, pathfindingTarget);
}
var path = nodeNetwork.GetPathOrClosest(ref Position, ref pathfindingTarget);
ai.Path.Clear();
var points = path.Select(item => item.Position).ToList();
while (points.Count > 0)
{
var length = (points[0] - Position).Length();
lineOfSightPathFindingPolygon.SetPoint(0, length / 2.0f, NavigationCollider.Radius);
lineOfSightPathFindingPolygon.SetPoint(1, length / 2.0f, -NavigationCollider.Radius);
lineOfSightPathFindingPolygon.SetPoint(2, -length / 2.0f, -NavigationCollider.Radius);
lineOfSightPathFindingPolygon.SetPoint(3, -length / 2.0f, NavigationCollider.Radius);
lineOfSightPathFindingPolygon.SetPoint(4, length / 2.0f, NavigationCollider.Radius);
lineOfSightPathFindingPolygon.X = (points[0].X + Position.X) / 2.0f;
lineOfSightPathFindingPolygon.Y = (points[0].Y + Position.Y) / 2.0f;
var angle = (float)System.Math.Atan2(points[0].Y - Position.Y, points[0].X - Position.X);
lineOfSightPathFindingPolygon.RotationZ = angle;
var hasClearPath = !solidCollisions.CollideAgainst(lineOfSightPathFindingPolygon) && !pitCollision.CollideAgainst(lineOfSightPathFindingPolygon);
if (hasClearPath && points.Count > 1)
{
points.RemoveAt(0);
}
else
{
break;
}
}
ai.Path.AddRange(points);
ai.Target = ai.Path.FirstOrDefault();
}
