/// <summary>
/// Implemented
/// </summary>
public void DrawLines(Pen pen, PointF[] points)
{
SvgPolylineElement pl = new SvgPolylineElement(points);
pl.Style = new SvgStyle(pen);
if (!_transforms.Result.IsIdentity)
pl.Transform = new SvgTransformList(_transforms.Top.Clone());
_cur.AddChild(pl);
DrawEndAnchors(pen, points[0], points[points.Length-1]);
}
/// <summary>
/// Implemented
/// </summary>
public void DrawLines(Pen pen, PointF[] points)
{
if (points.Length <= 1)
return;
if (IsEndAnchorSimple(pen.StartCap) && IsEndAnchorSimple(pen.EndCap))
{
// This code works, but not for CustomLineCap style
SvgPolylineElement pl = new SvgPolylineElement(points);
pl.Style = new SvgStyle(pen);
if (!_transforms.Result.IsIdentity)
pl.Transform = new SvgTransformList(_transforms.Top.Clone());
_cur.AddChild(pl);
DrawEndAnchors(pen, points[0], points[points.Length - 1]);
return;
}
// GraphicsPaths used in the constructor of CustomLineCap
// are private to the native GDI+ and for example the shape of AdjustableArrowCap
// is completely private to the native GDI+
//
// So in order to render the possibly any-shaped custom line caps we'll draw the line as GDI metafile and then reverse
// engineer the GDI metafile drawing and convert it to corresponding SVG commands
// Calculate the bounding rectangle
var minX = points[0].X;
var maxX = points[0].X;
var minY = points[0].Y;
var maxY = points[0].Y;
for (var i = 1; i < points.Length; i++)
{
var point = points[i];
minX = Math.Min(minX, point.X);
maxX = Math.Max(maxX, point.X);
minY = Math.Min(minY, point.Y);
maxY = Math.Max(maxY, point.Y);
}
var bounds = new RectangleF(minX, minY, maxX - minX + 1, maxY - minY + 1);
// Make the rectangle 0-based where "zero" represents the original shift
var zero = bounds.Location;
bounds.Offset(-zero.X, -zero.Y);
// Make the original point-path "zero"-based
for (var i = 0; i < points.Length; i++)
{
points[i].X -= zero.X;
points[i].Y -= zero.Y;
}
using (var metafileBuffer = new System.IO.MemoryStream())
{
System.Drawing.Imaging.Metafile metafile = null;
try
{
/* For discussion of tricky metafile details see:
* - http://nicholas.piasecki.name/blog/2009/06/drawing-o-an-in-memory-metafile-in-c-sharp/
* - http://stackoverflow.com/a/1533053/2626313
*/
using (var temporaryBitmap = new Bitmap(1, 1))
{
using (var temporaryCanvas = Graphics.FromImage(temporaryBitmap))
{
var hdc = temporaryCanvas.GetHdc();
metafile = new Metafile(
metafileBuffer,
hdc,
bounds,
MetafileFrameUnit.GdiCompatible,
EmfType.EmfOnly);
temporaryCanvas.ReleaseHdc();
}
}
using (var metafileCanvas = Graphics.FromImage(metafile))
{
metafileCanvas.DrawLines(pen, points);
}
}
finally
{
if (metafile != null)
metafile.Dispose();
}
metafileBuffer.Position = 0;
var metafileIsEmpty = true;
var parser = new MetafileTools.MetafileParser();
parser.EnumerateMetafile(metafileBuffer, pen.Width, zero, (PointF[] linePoints) =>
{
metafileIsEmpty = false;
SvgPolylineElement pl = new SvgPolylineElement(linePoints);
pl.Style = new SvgStyle(pen);
// Make it pretty
pl.Style.Set("stroke-linecap", "round");
if (!_transforms.Result.IsIdentity)
pl.Transform = new SvgTransformList(_transforms.Top.Clone());
_cur.AddChild(pl);
}, (PointF[] linePoints, Brush fillBrush) =>
{
// TODO: received shapes dont' have the vertex list "normalized" correctly
// metafileIsEmpty = false;
// FillPolygon(fillBrush, linePoints);
});
if (metafileIsEmpty)
{
// TODO: metafile recording on OpenSUSE Linux with Mono 3.8.0 does not seem to work at all
// as the supposed implementation in https://github.com/mono/libgdiplus/blob/master/src/graphics-metafile.c is
// full of "TODO". In this case we should take a graceful fallback approach
// Restore points array to the original values they had when entered the function
for (var i = 0; i < points.Length; i++)
{
points[i].X += zero.X;
points[i].Y += zero.Y;
}
SvgPolylineElement pl = new SvgPolylineElement(points);
pl.Style = new SvgStyle(pen);
if (!_transforms.Result.IsIdentity)
pl.Transform = new SvgTransformList(_transforms.Top.Clone());
_cur.AddChild(pl);
DrawEndAnchors(pen, points[0], points[points.Length - 1], ignoreUnsupportedLineCaps: true);
}
}
}
