public SegmentList Offset(float distance)
{
List <Line2> new_lines = new List <Line2>();
int N = lines.Count;
// Take each line and offset by distance, and store in
// new list
for (int i = 0; i < N; i++)
{
Line2 offset_line = lines[i].Line.Offset(distance);
new_lines.Add(offset_line);
}
List <LineSeg> result = new List <LineSeg>();
for (int i = 0; i < N; i++)
{
// i-th line
Line2 this_line = new_lines[i];
// Find index of previous line. If i-th is fist line,
// the j points to last line
int j = i > 0?i - 1:N - 1;
// Find index to next line. If i-th is the last line,
// then k points to fist line
int k = i < N - 1?i + 1:0;
Line2 prev_line = new_lines[j];
Line2 next_line = new_lines[k];
// Trim infinate line based on intersection with
// previous and next line.
LineSeg offset_seg = this_line.TrimBetween(prev_line, next_line);
result.Add(offset_seg);
}
// Create new polyline from array of line segments
return(new SegmentList(result.ToArray()));
}
void pictureBox1_MouseMove(object sender, MouseEventArgs e)
{
Point pt = e.Location;
if (HasCapturedLine)
{
int sel = Moving.index;
int dx = pt.X - Moving.StartMouseMovePoint.X;
int dy = pt.Y - Moving.StartMouseMovePoint.Y;
Point2 del = new Point2(DrawScale.Width * dx, DrawScale.Height * dy);
int prev_index = sel > 0?sel - 1:Count - 1;
int next_index = sel < Count - 1?sel + 1:0;
Point2 prev_pt = Poly.Lines[prev_index].StartPoint;
Point2 next_pt = Poly.Lines[next_index].EndPoint;
LineSeg tseg = new LineSeg(Moving.seg.StartPoint + del, Moving.seg.EndPoint + del);
Poly.Lines[prev_index] = new LineSeg(prev_pt, tseg.StartPoint);
Poly.Lines[sel] = tseg;
Poly.Lines[next_index] = new LineSeg(tseg.EndPoint, next_pt);
pictureBox1.Refresh();
this.Text = string.Format("x={0} y={1} Dragging Line={2}", pt.X, pt.Y, Selected);
}
else
{
if (Selected >= 0)
{
this.Text = string.Format("x={0} y={1} Hover Line={2}", pt.X, pt.Y, Selected);
}
else
{
this.Text = string.Format("x={0} y={1}", pt.X, pt.Y);
}
}
RefreshSelection(pt);
}
public static void DrawPipe(this Graphics g, float width, LineSeg seg, Color mid_color, Color edge_color)
{
DrawPipe(g, width, seg.StartPoint.Center, seg.EndPoint.Center, mid_color, edge_color);
}
public static void DrawLine(this Graphics g, LineSeg seg, Pen pen)
{
g.DrawLine(pen, seg.StartPoint.Center, seg.EndPoint.Center);
}