//Test if we should flip an edge
//a, b, c belongs to the triangle and d is the point on the other triangle
//a-c is the edge, which is important so we can flip it, by making the edge b-d
public static bool ShouldFlipEdge(MyVector2 a, MyVector2 b, MyVector2 c, MyVector2 d)
{
bool shouldFlipEdge = false;
//Use the circle test to test if we need to flip this edge
//We should flip if d is inside a circle formed by a, b, c
IntersectionCases intersectionCases = _Intersections.PointCircle(a, b, c, d);
if (intersectionCases == IntersectionCases.IsInside)
{
//Are these the two triangles forming a convex quadrilateral? Otherwise the edge cant be flipped
if (_Geometry.IsQuadrilateralConvex(a, b, c, d))
{
//If the new triangle after a flip is not better, then dont flip
//This will also stop the algorithm from ending up in an endless loop
IntersectionCases intersectionCases2 = _Intersections.PointCircle(b, c, d, a);
if (intersectionCases2 == IntersectionCases.IsOnEdge || intersectionCases2 == IntersectionCases.IsInside)
{
shouldFlipEdge = false;
}
else
{
shouldFlipEdge = true;
}
}
}
return(shouldFlipEdge);
}
//Is a point intersecting with a circle?
private void PointCircle()
{
MyVector2 testPoint = pointTrans.position.ToMyVector2();
MyVector2 circlePointA = t1_p1_trans.position.ToMyVector2();
MyVector2 circlePointB = t1_p2_trans.position.ToMyVector2();
MyVector2 circlePointC = t1_p3_trans.position.ToMyVector2();
//Is a point in a circle determines by three other points
IntersectionCases intersectionCases = _Intersections.PointCircle(circlePointA, circlePointB, circlePointC, testPoint);
//print(isPointInCircle);
//Display the circle
//if (intersectionCases == IntersectionCases.NoIntersection)
//{
// Gizmos.color = Color.white;
//}
//if (intersectionCases == IntersectionCases.IsInside)
//{
// Gizmos.color = Color.red;
//}
//if (intersectionCases == IntersectionCases.IsOnEdge)
//{
// Gizmos.color = Color.blue;
//}
MyVector2 centerOfCicle = _Geometry.CalculateCircleCenter(circlePointA, circlePointB, circlePointC);
float radius = MyVector2.Distance(centerOfCicle, circlePointA);
//Gizmos.DrawWireSphere(centerOfCicle.ToVector3(), radius);
////Display the points
//float pointRadius = 0.2f;
//Gizmos.DrawWireSphere(pointTrans.position, pointRadius);
//Gizmos.DrawWireSphere(t1_p1_trans.position, pointRadius);
//Gizmos.DrawWireSphere(t1_p2_trans.position, pointRadius);
//Gizmos.DrawWireSphere(t1_p3_trans.position, pointRadius);
//With mesh
//Big circle
TestAlgorithmsHelpMethods.DisplayCircleMesh(centerOfCicle, radius, 60, Color.white);
//Small circle
Color circleColor = (intersectionCases == IntersectionCases.IsInside) ? Color.red : Color.white;
TestAlgorithmsHelpMethods.DisplayCircleMesh(testPoint, 1f, 20, circleColor);
}
