/// <summary>
/// calc and return info on how two lines horizontally intersect each other.
/// </summary>
/// <param name="Line1"></param>
/// <param name="Line2"></param>
/// <returns></returns>
public static HorizontalIntersect HorizontalIntersect(
LineCoordinates Line1, LineCoordinates Line2)
{
HorizontalIntersect hi = null;
double iw;
double line1Ofs;
double line2Ofs;
if ((Line1.LeftMost <= Line2.LeftMost) && (Line1.RightMost >= Line2.LeftMost))
{
line1Ofs = Line2.LeftMost - Line1.LeftMost;
line2Ofs = 0;
if (Line1.RightMost < Line2.RightMost)
{
iw = Line1.RightMost - Line2.LeftMost + 1.00;
}
else
{
iw = Line2.Width;
}
}
else if ((Line2.LeftMost <= Line1.LeftMost) && (Line2.RightMost >= Line1.LeftMost))
{
line2Ofs = Line1.LeftMost - Line2.LeftMost;
line1Ofs = 0;
if (Line2.RightMost < Line1.RightMost)
{
iw = Line2.RightMost - Line1.LeftMost + 1.00;
}
else
{
iw = Line1.Width;
}
}
else
{
iw = 0;
line1Ofs = 0;
line2Ofs = 0;
}
hi = new HorizontalIntersect()
{
Length = iw,
Line1 = Line1,
Line1Ofs = line1Ofs,
Line2 = Line2,
Line2Ofs = line2Ofs
};
return(hi);
}
/// <summary>
/// compute the angle between two lines.
/// </summary>
/// <param name="Line1"></param>
/// <param name="Line2"></param>
/// <returns></returns>
public static double AngleBetween(LineCoordinates Line1, LineCoordinates Line2)
{
// the start point of each line is the common point between the two lines.
var commonPoint = LineCoordinates.CommonEndPoint(Line1, Line2);
// the end points of each line.
var end1 = Line1.OtherPoint(commonPoint);
var end2 = Line2.OtherPoint(commonPoint);
// the 360 degree angles of each line.
var angle1 = LineExt.GetAngle(commonPoint, end1);
var angle2 = LineExt.GetAngle(commonPoint, end2);
// the angle between is the diff between the 360 degree angles of the 2 lines.
var angleBet = Angle360.Subtract(angle1, angle2);
if (angleBet.Value > 180)
{
angleBet = Angle360.Subtract(angle2, angle1);
}
return(angleBet.Value);
}
/// <summary>
/// return the start/end points the two lines have in common. The two lines form a
/// vertex. The common end point is the point location of that vertex.
/// </summary>
/// <param name="Line1"></param>
/// <param name="Line2"></param>
/// <returns></returns>
public static Point CommonEndPoint(LineCoordinates Line1, LineCoordinates Line2)
{
if (Line1.Start.Equals(Line2.Start))
{
return(Line1.Start);
}
else if (Line1.End.Equals(Line2.Start))
{
return(Line1.End);
}
else if (Line1.Start.Equals(Line2.End))
{
return(Line1.Start);
}
else if (Line1.End.Equals(Line2.End))
{
return(Line1.End);
}
else
{
throw new ApplicationException("lines do not have end points in common");
}
}
public static LineVertexJunction TryMatchLines(
LineCoordinates Line1, LineCoordinates Line2)
{
return(null);
}
/// <summary>
/// Calc the point at which this line intersects with another line.
/// </summary>
/// <param name="Other"></param>
/// <returns></returns>
public static Point?IntersectPos(LineCoordinates Line1, LineCoordinates Line2)
{
// the x-axis range of this line does not intersect at all with the x-axis range
// of the other line.
if ((Line1.Start.X > Line2.End.X) || (Line1.End.X < Line2.Start.X))
{
return(null);
}
// the y-axis range of this line does not intersect at all with the y-axis range
// of the other line.
else if ((Line1.TopMost > Line2.BottomMost) || (Line1.BottomMost < Line2.TopMost))
{
return(null);
}
// lines are perpendicular. They intersect at the x-axis of the vertical line and
// the y-axis of the horizontal line.
else if (Line1.IsVertical && Line2.IsHorizontal)
{
return(new Point(Line1.Start.X, Line2.Start.Y));
}
else if (Line1.IsHorizontal && Line2.IsVertical)
{
return(new Point(Line1.Start.X, Line2.Start.Y));
}
// start pos of this line matches the start or end pos of the other line.
else if ((Line1.Start.Equals(Line2.Start)) || (Line1.Start.Equals(Line2.End)))
{
return(Line1.Start);
}
// end pos of this line matches the start or end pos of the other line.
else if ((Line1.End.Equals(Line2.Start)) || (Line1.End.Equals(Line2.End)))
{
return(Line2.End);
}
else
{
double i_x = 0.00;
double i_y = 0.00;
// char collisionDetected;
double s1_x, s1_y, s2_x, s2_y;
s1_x = Line1.End.X - Line1.Start.X;
s1_y = Line1.End.Y - Line1.Start.Y;
s2_x = Line2.End.X - Line2.Start.X;
s2_y = Line2.End.Y - Line2.Start.Y;
double s, t;
s = (-s1_y * (Line1.Start.X - Line2.Start.X) + s1_x * (Line1.Start.Y - Line2.Start.Y))
/ (-s2_x * s1_y + s1_x * s2_y);
t = (s2_x * (Line1.Start.Y - Line2.Start.Y) - s2_y * (Line1.Start.X - Line2.Start.X))
/ (-s2_x * s1_y + s1_x * s2_y);
if (s >= 0 && s <= 1 && t >= 0 && t <= 1)
{
// Collision detected
i_x = Line1.Start.X + (t * s1_x);
i_y = Line1.Start.Y + (t * s1_y);
return(new Point(i_x, i_y));
}
else
{
return(null);
}
}
#if skip
var hi = LineCoordinates.HorizontalIntersect(this, Other);
double leftMostX = hi.Line1.Start.X + hi.Line1Ofs;
TriangleVertex vertex1;
TriangleVertex vertex2;
// calc the location and angle of the vertex of the intersect triangle formed
// by line1.
{
Point? pos;
double angle;
if (hi.Line1Ofs > 0)
{
var adjLine = new HorizontalLineCoordinates(hi.Line1.Start, hi.Line1Ofs);
var oppLine = this.CalcOppositeSideLine(hi.Line1Ofs);
var rtTriangle = new RightTriangle()
{
AdjSide = adjLine,
OppSide = oppLine
};
pos = rtTriangle.OppVertex.Location;
}
else
{
pos = hi.Line1.Start;
}
angle = IntersectPos_CalcVertexAngle(hi.Line1.Angle);
vertex1 = new TriangleVertex()
{
Angle = angle,
Location = pos.Value
};
}
// calc the left side vertex of the intersect triangle formed by line2.
{
Point? pos;
double angle;
if (hi.Line2Ofs > 0)
{
var adjLine = new HorizontalLineCoordinates(hi.Line2.Start, hi.Line2Ofs);
var oppLine = this.CalcOppositeSideLine(hi.Line2Ofs);
var rtTriangle = new RightTriangle()
{
AdjSide = adjLine,
OppSide = oppLine
};
pos = rtTriangle.OppVertex.Location;
}
else
{
pos = hi.Line2.Start;
}
angle = IntersectPos_CalcVertexAngle(hi.Line2.Angle);
vertex2 = new TriangleVertex()
{
Angle = angle,
Location = pos.Value
};
}
// build the oblique triangle that is formed by the intersection of the
// two lines.
var obTriangle = new ObliqueTriangle()
{
Vertex1 = vertex1,
Vertex2 = vertex2
};
return(null);
}
