private void DrawLineToVertices(ref BottomPolygon[] poly)
{
Vector3 firstVert = new Vector3();
Vector2 endPos1 = new Vector2();
Segement ray;
Segement segement;
Vector3 endPos;
for (int ip = 0; ip < poly.Length; ip++)
{ //polygon
for (int iv = 0; iv < poly[ip].vertices.Length; iv++)
{
//vertices of the polygon
Color color = new Color(0F, 0.5F, 1F, 1F);
if (iv != 0)
{
color = colors[iv % 4];
}
Debug.DrawLine(player.transform.position, poly[ip].vertices[iv], color, 0F, false);
Debug.Log("verticezs " + poly[ip].vertices[iv] + " " + poly.Length + " " + poly[ip].vertices.Length);
if (iv == poly[ip].vertices.Length - 1)
{
firstVert = poly[ip].vertices[0];
}
else
{
firstVert = poly[ip].vertices[iv];
}
ray = new Segement(player.transform.position, source.position);
segement = new Segement(poly[ip].vertices[iv], firstVert);
endPos1 = myAlgoTest(ray, segement);
endPos = new Vector3(endPos1.x, 0, endPos1.y);
// Debug.Log ("OUT endPos " + poly[ip].vertices[iv] + " _ "+ source.position+ " _ "+ endPos);
if (endPos.x != int.MinValue && endPos.y != int.MaxValue)
{
Debug.DrawLine(player.transform.position, endPos, Color.red, 0F, false);
}
}
}
Debug.DrawLine(player.transform.position, source.position, Color.yellow, 0F, false);
}
private Vector2 myAlgoTest(Segement ray, Segement segment)
{
/*
*
* Point + Direction * T
*
* ------------------------------------------------------------------------
*
* Ray X = r_px+r_dx*T1
* Ray Y = r_py+r_dy*T1
* Segment X = s_px+s_dx*T2
* Segment Y = s_py+s_dy*T2
*
* ------------------------------------------------------------------------
*
* If the ray & segment intersect, their X & Y components will be the same:
* r_px + r_dx * T1 = s_px+s_dx*T2
* r_py + r_dy*T1 = s_py+s_dy*T2
*
* ------------------------------------------------------------------------
*
* Isolate T1 for both equations, getting rid of T1
* T1 = (s_px+s_dx*T2-r_px)/r_dx = (s_py+s_dy*T2-r_py)/r_dy
*
* Multiply both sides by r_dx * r_dy
* s_px*r_dy + s_dx*T2*r_dy - r_px*r_dy = s_py*r_dx + s_dy*T2*r_dx - r_py*r_dx
*
* Solve for T2!
* T2 = (r_dx*(s_py-r_py) + r_dy*(r_px-s_px))/(s_dx*r_dy - s_dy*r_dx)
*
* Plug the value of T2 to get T1
* T1 = (s_px+s_dx*T2-r_px)/r_dx
*
*
*/
Vector2 ret = new Vector2(int.MinValue, int.MaxValue);
// RAY in parametric: Point + Delta*T1
Vector2 rayPoint = new Vector2(ray.b.x, ray.b.y);
Vector2 rayDistance = new Vector2(ray.b.x - ray.a.x, ray.b.y - ray.a.y);
// SEGMENT in parametric: Point + Delta*T2
Vector2 segmentPoint = new Vector2(segment.a.x, segment.a.y);
Vector2 segmentDistance = new Vector2(segment.b.x - segment.a.x, segment.b.y - segment.a.y);
Debug.Log("!!!!!!!!!!!!!!!!!!!! segmentDistance = " + segment.ToString());
// Debug.Log ("in my function " + segmentPoint + " _ "+ rayPoint);
//Check if they're parallel
float rayMag = Mathf.Sqrt(rayDistance.x * rayDistance.x + rayDistance.y * rayDistance.y);
float segMag = Mathf.Sqrt(segmentDistance.x * segmentDistance.x + segmentDistance.y * segmentDistance.y);
//float rayMag = rayDistance.x+ rayDistance.y;
//float segMag = segmentDistance.x + segmentDistance.y;
if (rayDistance.x / rayMag == segmentDistance.x / segMag && rayDistance.y / rayMag == segmentDistance.y / segMag)
{
Debug.Log("Parallel case");
//they're parallel
return(new Vector2(int.MinValue, int.MinValue));
}
float t1 = 0, t2 = 0;
t2 = (rayDistance.x * (segmentPoint.y - rayPoint.x) + rayDistance.y * (rayPoint.x - segmentPoint.x)) / (segmentDistance.x * rayDistance.y - segmentDistance.y * rayDistance.x); ///(s_dx*r_dy - s_dy*r_dx);
t1 = (segmentPoint.x + segmentDistance.x * t2 - rayPoint.x) / rayDistance.x;
if (t1 < 0 || t2 < 0 || t2 > 1)
{
return(ret);
}
Debug.Log("Intersect found");
return(new Vector2(rayPoint.x + rayDistance.x * t1, rayPoint.y + rayDistance.y * t1));
//Yeah we found an intersect !
}
