| public static GetAngleBetweenLines ( IntPoint a1, IntPoint a2, IntPoint b1, IntPoint b2 ) : double | ||
| a1 | IntPoint | A point on the first line. |
| a2 | IntPoint | Another point on the first line. |
| b1 | IntPoint | A point on the second line. |
| b2 | IntPoint | Another point on the second line. |
| Résultat | double | |
public PolygonSubType CheckPolygonSubType(List <IntPoint> corners)
{
PolygonSubType polygonSubType = PolygonSubType.Unknown;
PointsCloud.GetBoundingRectangle(corners, out IntPoint minXY, out IntPoint maxXY);
IntPoint intPoint = maxXY - minXY;
float num = lengthError * (float)(intPoint.X + intPoint.Y) / 2f;
if (corners.Count == 3)
{
float angleBetweenVectors = GeometryTools.GetAngleBetweenVectors(corners[0], corners[1], corners[2]);
float angleBetweenVectors2 = GeometryTools.GetAngleBetweenVectors(corners[1], corners[2], corners[0]);
float angleBetweenVectors3 = GeometryTools.GetAngleBetweenVectors(corners[2], corners[0], corners[1]);
if (System.Math.Abs(angleBetweenVectors - 60f) <= angleError && System.Math.Abs(angleBetweenVectors2 - 60f) <= angleError && System.Math.Abs(angleBetweenVectors3 - 60f) <= angleError)
{
polygonSubType = PolygonSubType.EquilateralTriangle;
}
else
{
if (System.Math.Abs(angleBetweenVectors - angleBetweenVectors2) <= angleError || System.Math.Abs(angleBetweenVectors2 - angleBetweenVectors3) <= angleError || System.Math.Abs(angleBetweenVectors3 - angleBetweenVectors) <= angleError)
{
polygonSubType = PolygonSubType.IsoscelesTriangle;
}
if (System.Math.Abs(angleBetweenVectors - 90f) <= angleError || System.Math.Abs(angleBetweenVectors2 - 90f) <= angleError || System.Math.Abs(angleBetweenVectors3 - 90f) <= angleError)
{
polygonSubType = ((polygonSubType == PolygonSubType.IsoscelesTriangle) ? PolygonSubType.RectangledIsoscelesTriangle : PolygonSubType.RectangledTriangle);
}
}
}
else if (corners.Count == 4)
{
float angleBetweenLines = GeometryTools.GetAngleBetweenLines(corners[0], corners[1], corners[2], corners[3]);
float angleBetweenLines2 = GeometryTools.GetAngleBetweenLines(corners[1], corners[2], corners[3], corners[0]);
if (angleBetweenLines <= angleError)
{
polygonSubType = PolygonSubType.Trapezoid;
if (angleBetweenLines2 <= angleError)
{
polygonSubType = PolygonSubType.Parallelogram;
if (System.Math.Abs(GeometryTools.GetAngleBetweenVectors(corners[1], corners[0], corners[2]) - 90f) <= angleError)
{
polygonSubType = PolygonSubType.Rectangle;
}
float num2 = corners[0].DistanceTo(corners[1]);
float num3 = corners[0].DistanceTo(corners[3]);
if (System.Math.Abs(num2 - num3) <= num)
{
polygonSubType = ((polygonSubType == PolygonSubType.Parallelogram) ? PolygonSubType.Rhombus : PolygonSubType.Square);
}
}
}
else if (angleBetweenLines2 <= angleError)
{
polygonSubType = PolygonSubType.Trapezoid;
}
}
return(polygonSubType);
}
/// <summary>
/// Check sub type of a convex polygon.
/// </summary>
///
/// <param name="corners">Corners of the convex polygon to check.</param>
///
/// <returns>Return detected sub type of the specified shape.</returns>
///
/// <remarks><para>The method check corners of a convex polygon detecting
/// its subtype. Polygon's corners are usually retrieved using <see cref="IsConvexPolygon"/>
/// method, but can be any list of 3-4 points (only sub types of triangles and
/// quadrilateral are checked).</para>
///
/// <para>See <see cref="AngleError"/> and <see cref="LengthError"/> properties,
/// which set acceptable errors for polygon sub type checking.</para>
/// </remarks>
///
public PolygonSubType CheckPolygonSubType(List <IntPoint> corners)
{
PolygonSubType subType = PolygonSubType.Unknown;
// get bounding rectangle of the points list
IntPoint minXY, maxXY;
PointsCloud.GetBoundingRectangle(corners, out minXY, out maxXY);
// get cloud's size
IntPoint cloudSize = maxXY - minXY;
float maxLengthDiff = lengthError * (cloudSize.X + cloudSize.Y) / 2;
if (corners.Count == 3)
{
// get angles of the triangle
float angle1 = GeometryTools.GetAngleBetweenVectors(IntPoint.ToPoint(corners[0]), IntPoint.ToPoint(corners[1]), IntPoint.ToPoint(corners[2]));
float angle2 = GeometryTools.GetAngleBetweenVectors(IntPoint.ToPoint(corners[1]), IntPoint.ToPoint(corners[2]), IntPoint.ToPoint(corners[0]));
float angle3 = GeometryTools.GetAngleBetweenVectors(IntPoint.ToPoint(corners[2]), IntPoint.ToPoint(corners[0]), IntPoint.ToPoint(corners[1]));
// check for equilateral triangle
if ((Math.Abs(angle1 - 60) <= angleError) &&
(Math.Abs(angle2 - 60) <= angleError) &&
(Math.Abs(angle3 - 60) <= angleError))
{
subType = PolygonSubType.EquilateralTriangle;
}
else
{
// check for isosceles triangle
if ((Math.Abs(angle1 - angle2) <= angleError) ||
(Math.Abs(angle2 - angle3) <= angleError) ||
(Math.Abs(angle3 - angle1) <= angleError))
{
subType = PolygonSubType.IsoscelesTriangle;
}
// check for rectangled triangle
if ((Math.Abs(angle1 - 90) <= angleError) ||
(Math.Abs(angle2 - 90) <= angleError) ||
(Math.Abs(angle3 - 90) <= angleError))
{
subType = (subType == PolygonSubType.IsoscelesTriangle) ?
PolygonSubType.RectangledIsoscelesTriangle : PolygonSubType.RectangledTriangle;
}
}
}
else if (corners.Count == 4)
{
// get angles between 2 pairs of opposite sides
float angleBetween1stPair = GeometryTools.GetAngleBetweenLines(IntPoint.ToPoint(corners[0]), IntPoint.ToPoint(corners[1]), IntPoint.ToPoint(corners[2]), IntPoint.ToPoint(corners[3]));
float angleBetween2ndPair = GeometryTools.GetAngleBetweenLines(IntPoint.ToPoint(corners[1]), IntPoint.ToPoint(corners[2]), IntPoint.ToPoint(corners[3]), IntPoint.ToPoint(corners[0]));
// check 1st pair for parallelism
if (angleBetween1stPair <= angleError)
{
subType = PolygonSubType.Trapezoid;
// check 2nd pair for parallelism
if (angleBetween2ndPair <= angleError)
{
subType = PolygonSubType.Parallelogram;
// check angle between adjacent sides
if (Math.Abs(GeometryTools.GetAngleBetweenVectors(IntPoint.ToPoint(corners[1]), IntPoint.ToPoint(corners[0]), IntPoint.ToPoint(corners[2])) - 90) <= angleError)
{
subType = PolygonSubType.Rectangle;
}
// get length of 2 adjacent sides
float side1Length = (float)corners[0].DistanceTo(corners[1]);
float side2Length = (float)corners[0].DistanceTo(corners[3]);
if (Math.Abs(side1Length - side2Length) <= maxLengthDiff)
{
subType = (subType == PolygonSubType.Parallelogram) ?
PolygonSubType.Rhombus : PolygonSubType.Square;
}
}
}
else
{
// check 2nd pair for parallelism - last chence to detect trapezoid
if (angleBetween2ndPair <= angleError)
{
subType = PolygonSubType.Trapezoid;
}
}
}
return(subType);
}
