public static void DrawPolygon(Graphics graphics, Polygon pol, Brush brush, Pen pen, IViewport viewport)
{
if (pol.ExteriorRing == null)
{
return;
}
if (pol.ExteriorRing.Vertices.Count <= 2)
{
return;
}
//Use a graphics path instead of DrawPolygon. DrawPolygon has a problem with several interior holes
var gp = new GraphicsPath();
//Add the exterior polygon
gp.AddPolygon(GeometryRenderer.ConvertPoints(GeometryRenderer.WorldToScreen(pol.ExteriorRing, viewport)));
//Add the interior polygons (holes)
foreach (LinearRing linearRing in pol.InteriorRings)
{
gp.AddPolygon(GeometryRenderer.ConvertPoints(GeometryRenderer.WorldToScreen(linearRing, viewport)));
}
// Only render inside of polygon if the brush isn't null or isn't transparent
if (brush != null && brush != Brushes.Transparent)
{
graphics.FillPath(brush, gp);
}
// Create an outline if a pen style is available
if (pen != null)
{
graphics.DrawPath(pen, gp);
}
}
public static void Render(Graphics graphics, LineString line, Pen pen, IViewport viewport)
{
if (line.Vertices.Count > 1)
{
var gp = new GraphicsPath();
gp.AddLines(GeometryRenderer.ConvertPoints(GeometryRenderer.WorldToScreen(line, viewport)));
graphics.DrawPath(pen, gp);
}
}