/// <summary>
/// 构造直线，为两平面的交线
/// </summary>
public Line(Face face1, Face face2)
{
Vector3Double normalFace1 = face1.PlaneNormal;
Vector3Double normalFace2 = face2.PlaneNormal;
Direction = Vector3Double.Cross(normalFace1, normalFace2);
if (!(Direction.magnitude < EqualityTolerance)) // 两平面不平行
{
//getting a line point, zero is set to a coordinate whose direction
// 获取线上一点，方向坐标设为零点
//component isn't zero (line intersecting its origin plan)
// 成员不为零（线与第一个平面相交）
var d1 = -Vector3Double.Dot(normalFace1, face1.v1.Position);
var d2 = -Vector3Double.Dot(normalFace2, face2.v1.Position);
if (Math.Abs(Direction.x) > EqualityTolerance)
{
startPoint = new Vector3Double
{
x = 0,
y = (d2 * normalFace1.z - d1 * normalFace2.z) / Direction.x,
z = (d1 * normalFace2.y - d2 * normalFace1.y) / Direction.x
};
}
else if (Math.Abs(Direction.y) > EqualityTolerance)
{
startPoint = new Vector3Double
{
x = (d1 * normalFace2.z - d2 * normalFace1.z) / Direction.y,
y = 0,
z = (d2 * normalFace1.x - d1 * normalFace2.x) / Direction.y
};
}
else
{
startPoint = new Vector3Double
{
x = (d2 * normalFace1.y - d1 * normalFace2.y) / Direction.z,
y = (d1 * normalFace2.x - d2 * normalFace1.x) / Direction.z,
z = 0
};
}
}
else
{
startPoint = default;
}
Direction.Normalize();
}
/// <summary>
/// 用方向和起点构造射线
/// </summary>
/// <param name="direction">射线方向</param>
/// <param name="point">射线起点坐标</param>
public Line(Vector3Double direction, Vector3Double point)
{
Direction = direction;
startPoint = point;
direction.Normalize();
}
