private void drawPolylineSimple(Graphics g, Feature feature, PolylineStyle style, BoundingRectangle viewBox, double scaleFactor)
{
foreach (LinePath path in feature.Polyline.Paths)
{
if (path.Vertices.Count < 2)
continue;
PointF[] points = new PointF[path.Vertices.Count];
for (int j = 0; j < path.Vertices.Count; j++)
{
points[j].X = (float)((path.Vertices[j].X - viewBox.MinX) * scaleFactor);
points[j].Y = (float)((viewBox.MaxY - path.Vertices[j].Y) * scaleFactor);
}
//selection and Stroke
if (style.UseOutline || feature.Selected)
drawLinePathSelectionAndOutline(g, feature.Selected, points, style);
using (Pen pen = style.GetPen())
{
pen.DashOffset = 0;
//main polyline
g.DrawLines(pen, points);
if (style.UseAnnexLine)
using (Pen annexPen = style.GetAnnexPen())
{
// additional line
g.DrawLines(annexPen, points);
}
}
}
}
/// <summary>
/// Drawing the line.
/// </summary>
protected virtual void DrawPolyline(Feature feature, Graphics g, PolylineStyle style, TitleStyle titleStyle,
BoundingRectangle viewBox, bool titleVisible, double scaleFactor)
{
if (!_isSelectionRendering && feature.Selected)
{
PolylineBufferElement element = new PolylineBufferElement(feature, style, titleStyle, titleVisible);
_selectedPolylines.Add(element);
return;
}
double pixelsize = 1/scaleFactor;
if (_reduceSubpixelDetails)
{
if (feature.BoundingRectangle.Width < pixelsize && feature.BoundingRectangle.Height < pixelsize)
return;
Polyline p1 = (Polyline) feature.Polyline.Clone();
p1.Weed(pixelsize);
Feature tempFeature = new Feature(FeatureType.Polyline);
tempFeature.Title = feature.Title;
tempFeature.Selected = feature.Selected;
tempFeature.Polyline = p1;
feature = tempFeature;
if (feature.Polyline.Paths.Count == 0)
return;
}
using (Pen pen = style.GetPen())
{
if (Math.Min(viewBox.Width/(feature.BoundingRectangle.Width),
viewBox.Height/(feature.BoundingRectangle.Height)) < 2)
drawPolylineWithIntersectCalculation(g, feature, style, viewBox, scaleFactor);
else
drawPolylineSimple(g, feature, style, viewBox, scaleFactor);
// inscription
if (!string.IsNullOrEmpty(feature.Title) && titleVisible)
addTitleBufferElement(g, feature, titleStyle, viewBox, scaleFactor);
}
}
private void drawPolylineWithIntersectCalculation(Graphics g, Feature feature, PolylineStyle style, BoundingRectangle viewBox, double scaleFactor)
{
//selection and rims do not contain dashes, so it is better to paint the entire
if (style.UseOutline || feature.Selected)
{
foreach (LinePath path in feature.Polyline.Paths)
{
PointF[] points = new PointF[path.Vertices.Count];
for (int j = 0; j < path.Vertices.Count; j++)
{
points[j].X = (float)((path.Vertices[j].X - viewBox.MinX) * scaleFactor);
points[j].Y = (float)((viewBox.MaxY - path.Vertices[j].Y) * scaleFactor);
}
if (style.UseOutline || feature.Selected)
drawLinePathSelectionAndOutline(g, feature.Selected, points, style);
}
}
List<ICoordinate> currentPath = new List<ICoordinate>();
using (Pen pen = style.GetPen())
{
using(Pen annexPen = style.GetAnnexPen())
foreach (LinePath path in feature.Polyline.Paths)
{
if (path.Vertices.Count < 2)
continue;
currentPath.Clear();
double currentLength = 0;
bool isInternalPath = viewBox.ContainsPoint(path.Vertices[0]);
ICoordinate previousPoint = path.Vertices[0];
IList<ICoordinate> vertices = path.Vertices;
for (int j = 0; j < path.Vertices.Count; j++)
{
if (isInternalPath) // the inside of the polyline
{
if (viewBox.ContainsPoint(vertices[j])) //stay inside
{
currentPath.Add(vertices[j]);
continue;
}
else // go outside
{
// add a point of intersection
List<ICoordinate> crossPoints = getCrossPoints(vertices[j], vertices[j - 1], viewBox);
currentPath.Add(crossPoints[0]);
//draw
drawVisiblePolylinePartWithStyleDetection(g, currentPath, style, pen, annexPen, feature.Selected, viewBox, scaleFactor, currentLength);
// are counting the length of a past
currentLength += getPathLength(currentPath);
// initialize the array outside of the points, polylines and continue execution
currentPath.Clear();
currentPath.Add(crossPoints[0]);
currentPath.Add(vertices[j]);
isInternalPath = false;
continue;
}
}
else //the outer part of the polyline
{
if (viewBox.ContainsPoint(vertices[j])) // go inside
{
//add a point of intersection
List<ICoordinate> crossPoints = getCrossPoints(vertices[j], vertices[j - 1], viewBox);
currentPath.Add(crossPoints[0]);
//are counting the length of a past
currentLength += getPathLength(currentPath);
// initialize the array of points inside the polyline and continue execution
currentPath.Clear();
currentPath.Add(crossPoints[0]);
currentPath.Add(vertices[j]);
isInternalPath = true;
continue;
}
else // cross twice, or remain outside
{
// look for the point of intersection
if (j > 0)
{
List<ICoordinate> crossPoints = getCrossPoints(vertices[j], vertices[j - 1], viewBox);
if (crossPoints.Count == 0) // remained outside
{
currentPath.Add(vertices[j]);
continue;
}
if (crossPoints.Count == 2) // crossed 2 times
{
//determine which of the points of intersection must be added to the current path
double d0 = PlanimetryAlgorithms.Distance(crossPoints[0], vertices[j - 1]);
double d1 = PlanimetryAlgorithms.Distance(crossPoints[1], vertices[j - 1]);
if (d0 < d1)
currentPath.Add(crossPoints[0]);
else
currentPath.Add(crossPoints[1]);
// are counting the length of a past
currentLength += getPathLength(currentPath);
currentPath.Clear();
currentPath.Add(crossPoints[d0 < d1 ? 0 : 1]);
currentPath.Add(crossPoints[d0 < d1 ? 1 : 0]);
//draw a segment
drawVisiblePolylinePartWithStyleDetection(g, currentPath, style, pen, annexPen, feature.Selected, viewBox, scaleFactor, currentLength);
// consider the length
currentLength += PlanimetryAlgorithms.Distance(crossPoints[0], crossPoints[1]);
// initialize the external part of the polyline
currentPath.Clear();
if (d0 < d1)
currentPath.Add(crossPoints[1]);
else
currentPath.Add(crossPoints[0]);
currentPath.Add(vertices[j]);
isInternalPath = false;
continue;
}
}
else // 1st point you just need to add to the list
{
currentPath.Add(vertices[j]);
continue;
}
}
}
}
//Draw a polyline part, if the internal
if (isInternalPath)
drawVisiblePolylinePartWithStyleDetection(g, currentPath, style, pen, annexPen, feature.Selected, viewBox, scaleFactor, currentLength);
}
}
}