public static bool LineIntersection(myAABB box, Vector3 StartPoint, Vector3 EndPoint, out Vector3 IntersectionPoint)
{
//define initial lowest and highest
float Lowest = 0.0f;
float Highest = 1.0f;
//default value for intersection point is needed
IntersectionPoint = Vector3.zero;
//we do an intersection check on every axis by resuing the IntersectingAxis function
if (!IntersectingAxis(Vector3.right, box, StartPoint, EndPoint, ref Lowest, ref Highest))
{
return(false);
}
if (!IntersectingAxis(Vector3.up, box, StartPoint, EndPoint, ref Lowest, ref Highest))
{
return(false);
}
if (!IntersectingAxis(Vector3.forward, box, StartPoint, EndPoint, ref Lowest, ref Highest))
{
return(false);
}
//caulculate intersection point through interpolation
IntersectionPoint = VectorMaths.LERP(StartPoint, EndPoint, Lowest);
return(true);
}
public static bool Intersects(myAABB b1, myAABB b2)
{
//checks each individual face in the bounding box to see if there are intersections
return(!(b2.Left > b1.Right ||
b2.Right < b1.Left ||
b2.Top < b1.Bottom ||
b2.Bottom > b1.Top ||
b2.Back > b1.Front ||
b2.Front < b1.Back));
}
//will move slowly towards the sun until it collides
void Update()
{
distance += Time.deltaTime;
transform.position = new Vector3(-40 + distance, 0, -10);
Vector3 temp = transform.position;
//creating the bounding box for the UFO
Vector3 minextent = new Vector3(temp.x - 4, temp.y - 4, temp.z - 4);
Vector3 maxextent = new Vector3(temp.x + 4, temp.y + 4, temp.z + 4);
UFOBOX = new myAABB(minextent, maxextent);
}
public static bool IntersectingAxis(Vector3 Axis, myAABB box, Vector3 StartPoint, Vector3 EndPoint, ref float Lowest, ref float Highest)
{
//calculate minimum and maximum based on current axis
float Minimum = 0.0f, Maximum = 1.0f;
if (Axis == Vector3.right)
{
Minimum = (box.Left - StartPoint.x) / (EndPoint.x - StartPoint.x);
Maximum = (box.Right - StartPoint.x) / (EndPoint.x - StartPoint.x);
}
else if (Axis == Vector3.up)
{
Minimum = (box.Bottom - StartPoint.y) / (EndPoint.y - StartPoint.y);
Maximum = (box.Top - StartPoint.y) / (EndPoint.y - StartPoint.y);
}
else if (Axis == Vector3.forward)
{
Minimum = (box.Back - StartPoint.z) / (EndPoint.z - StartPoint.z);
Maximum = (box.Front - StartPoint.z) / (EndPoint.z - StartPoint.z);
}
if (Maximum < Minimum)
{
//swap the values
float temp = Maximum;
Maximum = Minimum;
Minimum = temp;
}
//eliminate non-intersections early
if (Maximum < Lowest)
{
return(false);
}
if (Minimum > Highest)
{
return(false);
}
Lowest = Mathf.Max(Minimum, Lowest);
Highest = Mathf.Min(Maximum, Highest);
if (Lowest > Highest)
{
return(false);
}
return(true);
}
void Update()
{
if (destroyed == false)
{
//gets the value of the bounding box on the UFO and compares it to a box created around this object.
UFOStuff UFOScript = UFO.GetComponent <UFOStuff>();
myAABB UFObox = UFOScript.UFOBOX;
Vector3 temp = transform.position;
Vector3 minextent = new Vector3(temp.x - 15, temp.y - 15, temp.z - 15);
Vector3 maxextent = new Vector3(temp.x + 15, temp.y + 15, temp.z + 15);
myAABB box = new myAABB(minextent, maxextent);
//if the bounding box of the UFO intersects with this bounding box the UFO is destroyed
if (myAABB.Intersects(box, UFObox))
{
Destroy(UFO);
destroyed = true;
}
}
}
