public static RayCastResult RayCast(IEnumerable <Polygon> polygons, Vector2 startPoint, float length, float direction, float precision = 0.5f)
{
//bool flag = false;
//float minLen = float.MaxValue;
RayCastResult result = new RayCastResult();
result.RayLength = length;
result.Collides = false;
result.CollisionPoint = GameMath.LengthDir(length, direction) + startPoint;
foreach (Polygon poly in polygons)
{
RayCastResult res = RayCast(poly, startPoint, length, direction, precision);
if (res.Collides)
{
if (res.RayLength < result.RayLength)
{
result.RayLength = res.RayLength;
result.CollisionPoint = res.CollisionPoint;
}
result.Collides = true;
}
}
return(result);
}
public static RayCastResult RayCast(Polygon polygon, Vector2 startPoint, float length, float direction, float precision = 0.5f)
{
RayCastResult result = new RayCastResult();
result.Collides = true;
Vector2 endPoint = GameMath.LengthDir(length, direction) + startPoint;
result.CollisionPoint = endPoint;
Polygon line = new Polygon();
line.m_isConvex = true;
line.m_isConvexNeedUpdate = false;
line.AddPoint(startPoint);
line.AddPoint(endPoint);
if (!polygon.Collision(line) || polygon.Contains(startPoint))
{
result.Collides = false;
return(result);
}
float min = 0f;
float max = length;
float q = length;
while (max - min > precision)
{
q = (min + max) / 2;
line[1] = GameMath.LengthDir(q, direction) + startPoint;
if (polygon.Collision(line))
{
max = q;
}
else
{
min = q + precision;
}
}
result.CollisionPoint = line[1];
result.RayLength = q;
return(result);
}
