//Convert a plane defined by 3 points to a plane defined by a vector and a point.
//The plane point is the middle of the triangle defined by the 3 points.
public static ExtPlane PlaneFrom3Points(Vector3 pointA, Vector3 pointB, Vector3 pointC)
{
Vector3 planeNormal = Vector3.zero;
Vector3 planePoint = Vector3.zero;
//Make two vectors from the 3 input points, originating from point A
Vector3 AB = pointB - pointA;
Vector3 AC = pointC - pointA;
//Calculate the normal
planeNormal = Vector3.Normalize(Vector3.Cross(AB, AC));
//Get the points in the middle AB and AC
Vector3 middleAB = pointA + (AB / 2.0f);
Vector3 middleAC = pointA + (AC / 2.0f);
//Get vectors from the middle of AB and AC to the point which is not on that line.
Vector3 middleABtoC = pointC - middleAB;
Vector3 middleACtoB = pointB - middleAC;
//Calculate the intersection between the two lines. This will be the center
//of the triangle defined by the 3 points.
//We could use LineLineIntersection instead of ClosestPointsOnTwoLines but due to rounding errors
//this sometimes doesn't work.
Vector3 temp;
ExtLine.ClosestPointsOnTwoLines(out planePoint, out temp, middleAB, middleABtoC, middleAC, middleACtoB);
return(new ExtPlane(planePoint, planeNormal, true));
}
public ExtLine3d(Vector3 position, Quaternion rotation, Vector3 localScale) : this()
{
_position = position;
_rotation = rotation;
_localScale = localScale;
_lineLocalPosition = new ExtLine(new Vector3(0, 0, 0.4f), new Vector3(0, 0, -0.4f));
UpdateMatrix();
}
/// <summary>
/// Calculates the intersection line segment between 2 lines (not segments).
/// Returns false if no solution can be found.
/// </summary>
/// <returns></returns>
public static bool CalculateLineLineIntersection3d(ExtLine line1, ExtLine line2, out Vector3 resulmtSegmentPoint1, out Vector3 resultSegmentPoint2)
{
return(CalculateLineLineIntersection3d(line1._p1, line1._p2, line2._p1, line2._p2, out resulmtSegmentPoint1, out resultSegmentPoint2));
}
/// <summary>
/// return percentage (from 0 to 1) of the position of the C vector
/// </summary>
public static float GetPercentageInLineFromPosition(ExtLine line, Vector3 c)
{
return(GetPercentageInLineFromPosition(line._p1, line._p2, c));
}
/// <summary>
/// return the point at a given percentage of a line
/// </summary>
/// <param name="percentage">0 to 1</param>
/// <returns></returns>
public static Vector3 GetPositionInLineFromPercentage(ExtLine line, float percentage)
{
return(GetPositionInLineFromPercentage(line._p1, line._p2, percentage));
}
