//--------------------------------------------------------------------------------------------
//Проверка параллельности прямых
public static bool AreLinesParallel(LineDescriptor lineOne, LineDescriptor lineTwo)
{
bool isParallel =
(lineOne.coefficientOfX / lineOne.coefficientOfY) ==
(lineTwo.coefficientOfX / lineTwo.coefficientOfY);
return(isParallel);
}
//-----------------------------------------------------------------------------------------------
//Расстояние от точки до прямой
public static double DistanceFromPointToLine(Point2D point, LineDescriptor lineDescriptor)
{
double a = lineDescriptor.CoefficientOfX;
double b = lineDescriptor.CoefficientOfY;
double c = lineDescriptor.AbsoluteTerm;
double distance = (a * point.X + b * point.Y + c) / Math.Sqrt(a * a + b * b);
return(distance);
}
//-----------------------------------------------------------------------------------------------
//Прямя по двум точкам
public static LineDescriptor GetLineDescriptor(Point2D pointOne, Point2D pointTwo)
{
double coefficientOfX = pointTwo.Y;
double coefficientOfY = pointOne.X - pointTwo.X;
double absoluteTerm = pointOne.X * pointTwo.Y + pointOne.Y * pointTwo.X;
LineDescriptor lineDescriptor =
new LineDescriptor(coefficientOfX, coefficientOfY, absoluteTerm);
return(lineDescriptor);
}
//------------------------------------------------------------------------------------------------
//Нормаль к кривой в точке
public LineDescriptor GetNormalAtPoint(Point2D point)
{
double x0 = point.X;
double y0 = point.Y;
double a = a12 * x0 + a22 * y0 + a23;
double b = -a11 * x0 - a12 * y0 - a13;
double c =
a11 * x0 * y0 + a12 * y0 * y0 + a13 * y0 - a12 * x0 * x0 - a22 * y0 * x0 - a23 * x0;
LineDescriptor normalLineDescriptor = new LineDescriptor(a, b, c);
return(normalLineDescriptor);
}
//-----------------------------------------------------------------------------------------------
//Точки пересечения прямой и окружности
public static Point2D[] IntersectionPointsOfLineAndCircle(
LineDescriptor lineDescriptor,
CircleDescriptor circleDescriptor
)
{
double a = lineDescriptor.CoefficientOfX;
double b = lineDescriptor.CoefficientOfY;
double c = lineDescriptor.AbsoluteTerm;
double xc = circleDescriptor.Centre.X;
double yc = circleDescriptor.Centre.Y;
double r = circleDescriptor.Radius;
double x1, x2, y1, y2;
if (b != 0)
{
double koefficientA = 1 + ((a * a) / (b * b));
double koefficientB = 2 * (c * a / (b * b) + yc * a / b - xc);
double koefficientC =
xc * xc + yc * yc + (c * c) / (b * b) + 2 * yc * c / b - r * r;
QuadraticEquation quadraticEquation =
new QuadraticEquation(koefficientA, koefficientB, koefficientC);
Complex[] complexRoots = quadraticEquation.GetRoots();
double[] realRoots = NumbersManager.GetRealParts(complexRoots);
x1 = realRoots[0];
y1 = (-c - a * x1) / b;
x2 = realRoots[1];
y2 = (-c - a * x2) / b;
}
else
{
double x = -c / a;
x1 = x2 = x;
double[] coordinatesY = circleDescriptor.GetCoordinatesY(x);
y1 = coordinatesY[0];
y2 = coordinatesY[1];
}
Point2D intersectionPoint1 = new Point2D(x1, y1);
Point2D intersectionPoint2 = new Point2D(x2, y2);
Point2D[] intersectionPoints = new Point2D[] { intersectionPoint1, intersectionPoint2 };
return(intersectionPoints);
}
//-----------------------------------------------------------------------------------------------
//Точка пересечения двух прямых линий
public static Point2D IntersectionPointOfLines(LineDescriptor lineOne, LineDescriptor lineTwo)
{
double a1 = lineOne.CoefficientOfX;
double b1 = lineOne.CoefficientOfY;
double c1 = lineOne.AbsoluteTerm;
double a2 = lineTwo.CoefficientOfX;
double b2 = lineTwo.CoefficientOfY;
double c2 = lineTwo.AbsoluteTerm;
double y = ((a2 * c1 / a1) - c2) / (b2 - (a2 * b1 / a1));
double x = (-c1 - b1 * y) / a1;
Point2D intersectionPoint = new Point2D(x, y);
return(intersectionPoint);
}