private void ReadTextSpans(XElement e, SKCanvas canvas, SKPoint location, SKPaint stroke, SKPaint fill)
{
var nodes = e.Nodes().ToArray();
for (int i = 0; i < nodes.Length; i++)
{
var c = nodes[i];
bool isFirst = i == 0;
bool isLast = i == nodes.Length - 1;
if (c.NodeType == XmlNodeType.Text)
{
// TODO: check for preserve whitespace
var textSegments = ((XText)c).Value.Split(new[] { '\n', '\r' }, StringSplitOptions.RemoveEmptyEntries);
var count = textSegments.Length;
if (count > 0)
{
if (isFirst)
{
textSegments[0] = textSegments[0].TrimStart();
}
if (isLast)
{
textSegments[count - 1] = textSegments[count - 1].TrimEnd();
}
var text = WSRe.Replace(string.Concat(textSegments), " ");
canvas.DrawText(text, location.X, location.Y, fill);
location.X += fill.MeasureText(text);
}
}
else if (c.NodeType == XmlNodeType.Element)
{
var ce = (XElement)c;
if (ce.Name.LocalName == "tspan")
{
var spanFill = fill.Clone();
// the current span may want to change the cursor position
location.X = ReadOptionalNumber(ce.Attribute("x")) ?? location.X;
location.Y = ReadOptionalNumber(ce.Attribute("y")) ?? location.Y;
ReadFontAttributes(ce, spanFill);
var text = ce.Value.Trim();
canvas.DrawText(text, location.X, location.Y, spanFill);
location.X += spanFill.MeasureText(text);
}
}
}
}
private void ReadElement(XElement e, SKCanvas canvas, SKPaint stroke, SKPaint fill)
{
ReadPaints(e, ref stroke, ref fill);
// transform matrix
var transform = ReadTransform(e.Attribute("transform")?.Value ?? string.Empty);
canvas.Save();
canvas.Concat(ref transform);
// SVG elements
var elementName = e.Name.LocalName;
switch (elementName)
{
case "text":
if (stroke != null || fill != null)
{
ReadText(e, canvas, stroke?.Clone(), fill?.Clone());
}
break;
case "rect":
if (stroke != null || fill != null)
{
var x = ReadNumber(e.Attribute("x"));
var y = ReadNumber(e.Attribute("y"));
var width = ReadNumber(e.Attribute("width"));
var height = ReadNumber(e.Attribute("height"));
var rx = ReadNumber(e.Attribute("rx"));
var ry = ReadNumber(e.Attribute("ry"));
var rect = SKRect.Create(x, y, width, height);
if (rx > 0 || ry > 0)
{
if (fill != null)
{
canvas.DrawRoundRect(rect, rx, ry, fill);
}
if (stroke != null)
{
canvas.DrawRoundRect(rect, rx, ry, stroke);
}
}
else
{
if (fill != null)
{
canvas.DrawRect(rect, fill);
}
if (stroke != null)
{
canvas.DrawRect(rect, stroke);
}
}
}
break;
case "ellipse":
if (stroke != null || fill != null)
{
var cx = ReadNumber(e.Attribute("cx"));
var cy = ReadNumber(e.Attribute("cy"));
var rx = ReadNumber(e.Attribute("rx"));
var ry = ReadNumber(e.Attribute("ry"));
if (fill != null)
{
canvas.DrawOval(cx, cy, rx, ry, fill);
}
if (stroke != null)
{
canvas.DrawOval(cx, cy, rx, ry, stroke);
}
}
break;
case "circle":
if (stroke != null || fill != null)
{
var cx = ReadNumber(e.Attribute("cx"));
var cy = ReadNumber(e.Attribute("cy"));
var rr = ReadNumber(e.Attribute("r"));
if (fill != null)
{
canvas.DrawCircle(cx, cy, rr, fill);
}
if (stroke != null)
{
canvas.DrawCircle(cx, cy, rr, stroke);
}
}
break;
case "path":
if (stroke != null || fill != null)
{
var d = e.Attribute("d")?.Value;
if (!string.IsNullOrWhiteSpace(d))
{
var path = SKPath.ParseSvgPathData(d);
if (fill != null)
{
canvas.DrawPath(path, fill);
}
if (stroke != null)
{
canvas.DrawPath(path, stroke);
}
}
}
break;
case "polygon":
case "polyline":
if (stroke != null || fill != null)
{
var close = elementName == "polygon";
var p = e.Attribute("points")?.Value;
if (!string.IsNullOrWhiteSpace(p))
{
var path = ReadPolyPath(p, close);
if (fill != null)
{
canvas.DrawPath(path, fill);
}
if (stroke != null)
{
canvas.DrawPath(path, stroke);
}
}
}
break;
case "g":
if (e.HasElements)
{
foreach (var gElement in e.Elements())
{
ReadElement(gElement, canvas, stroke?.Clone(), fill?.Clone());
}
}
break;
case "use":
if (e.HasAttributes)
{
var href = ReadHref(e);
if (href != null)
{
// TODO: copy/process other attributes
var x = ReadNumber(e.Attribute("x"));
var y = ReadNumber(e.Attribute("y"));
var useTransform = SKMatrix.MakeTranslation(x, y);
canvas.Save();
canvas.Concat(ref useTransform);
ReadElement(href, canvas, stroke?.Clone(), fill?.Clone());
canvas.Restore();
}
}
break;
case "line":
if (stroke != null)
{
var x1 = ReadNumber(e.Attribute("x1"));
var x2 = ReadNumber(e.Attribute("x2"));
var y1 = ReadNumber(e.Attribute("y1"));
var y2 = ReadNumber(e.Attribute("y2"));
canvas.DrawLine(x1, y1, x2, y2, stroke);
}
break;
case "switch":
if (e.HasElements)
{
foreach (var ee in e.Elements())
{
var requiredFeatures = ee.Attribute("requiredFeatures");
var requiredExtensions = ee.Attribute("requiredExtensions");
var systemLanguage = ee.Attribute("systemLanguage");
// TODO: evaluate requiredFeatures, requiredExtensions and systemLanguage
var isVisible =
requiredFeatures == null &&
requiredExtensions == null &&
systemLanguage == null;
if (isVisible)
{
ReadElement(ee, canvas, stroke?.Clone(), fill?.Clone());
}
}
}
break;
case "defs":
case "title":
case "desc":
case "description":
// already read earlier
break;
default:
LogOrThrow($"SVG element '{elementName}' is not supported");
break;
}
// restore matrix
canvas.Restore();
}
