public static void RenderTexture(SKCanvas canvas, SKBitmap bitmap, float x, float y, float orientation = 0,
float offsetX = 0, float offsetY = 0,
LabelStyle.HorizontalAlignmentEnum horizontalAlignment = LabelStyle.HorizontalAlignmentEnum.Center,
LabelStyle.VerticalAlignmentEnum verticalAlignment = LabelStyle.VerticalAlignmentEnum.Center,
float opacity = 1f,
float scale = 1f)
{
canvas.Save();
canvas.Translate(x, y);
canvas.RotateDegrees(orientation, 0, 0); // todo: or degrees?
canvas.Scale(scale, scale);
x = offsetX + DetermineHorizontalAlignmentCorrection(horizontalAlignment, bitmap.Width);
y = -offsetY + DetermineVerticalAlignmentCorrection(verticalAlignment, bitmap.Height);
var halfWidth = bitmap.Width/2;
var halfHeight = bitmap.Height/2;
var rect = new SKRect(x - halfWidth, y - halfHeight, x + halfWidth, y + halfHeight);
RenderTexture(canvas, bitmap, rect, opacity);
canvas.Restore();
}
public SKAutoCanvasRestore(SKCanvas canvas, bool doSave)
{
this.canvas = canvas;
this.saveCount = 0;
if (canvas != null) {
saveCount = canvas.SaveCount;
if (doSave) {
canvas.Save ();
}
}
}
public SKAutoCanvasRestore(SKCanvas canvas, bool doSave)
{
this.canvas = canvas;
this.saveCount = 0;
if (canvas != null)
{
saveCount = canvas.SaveCount;
if (doSave)
{
canvas.Save();
}
}
}
public static void ManageDrawMatrix(SKCanvas canvas, int width, int height)
{
var size = ((float)height > width ? width : height) * 0.5f;
var center = new SKPoint((width - size) / 2f, (height - size) / 2f);
// draw these at specific locations
var leftRect = SKRect.Create(center.X - size / 2f, center.Y, size, size);
var rightRect = SKRect.Create(center.X + size / 2f, center.Y, size, size);
// draw this at the current location / transformation
var rotatedRect = SKRect.Create(0f, 0f, size, size);
using (var paint = new SKPaint()) {
paint.IsAntialias = true;
canvas.Clear(XamPurple);
// draw
paint.Color = XamDkBlue;
canvas.DrawRect(leftRect, paint);
// save
canvas.Save();
// transform
canvas.Translate(width / 2f, center.Y);
canvas.RotateDegrees(45);
// draw
paint.Color = XamGreen;
canvas.DrawRoundRect(rotatedRect, 10, 10, paint);
// undo transform / restore
canvas.Restore();
// draw
paint.Color = XamLtBlue;
canvas.DrawRect(rightRect, paint);
}
}
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();
}
public void Save() => _canvas.Save();
private SKPoint DrawLineArrowInternal(SKCanvas canvas, SKPaint pen, SKPaint brush, float x, float y, double angle, ArrowStyle style)
{
SKPoint pt = default(SKPoint);
var rt = MatrixHelper.Rotation(angle, new SKPoint(x, y));
double rx = style.RadiusX;
double ry = style.RadiusY;
double sx = 2.0 * rx;
double sy = 2.0 * ry;
switch (style.ArrowType)
{
default:
case ArrowType.None:
{
pt = new SKPoint(x, y);
}
break;
case ArrowType.Rectangle:
{
pt = MatrixHelper.TransformPoint(rt, new SKPoint(x - (float)sx, y));
var rect = ToSKRect(x - sx, y - ry, sx, sy);
int count = canvas.Save();
canvas.SetMatrix(rt);
DrawRectangleInternal(canvas, brush, pen, style.IsStroked, style.IsFilled, ref rect);
canvas.RestoreToCount(count);
}
break;
case ArrowType.Ellipse:
{
pt = MatrixHelper.TransformPoint(rt, new SKPoint(x - (float)sx, y));
int count = canvas.Save();
canvas.SetMatrix(rt);
var rect = ToSKRect(x - sx, y - ry, sx, sy);
DrawEllipseInternal(canvas, brush, pen, style.IsStroked, style.IsFilled, ref rect);
canvas.RestoreToCount(count);
}
break;
case ArrowType.Arrow:
{
var pts = new SKPoint[]
{
new SKPoint(x, y),
new SKPoint(x - (float)sx, y + (float)sy),
new SKPoint(x, y),
new SKPoint(x - (float)sx, y - (float)sy),
new SKPoint(x, y)
};
pt = MatrixHelper.TransformPoint(rt, pts[0]);
var p11 = MatrixHelper.TransformPoint(rt, pts[1]);
var p21 = MatrixHelper.TransformPoint(rt, pts[2]);
var p12 = MatrixHelper.TransformPoint(rt, pts[3]);
var p22 = MatrixHelper.TransformPoint(rt, pts[4]);
DrawLineInternal(canvas, pen, style.IsStroked, ref p11, ref p21);
DrawLineInternal(canvas, pen, style.IsStroked, ref p12, ref p22);
}
break;
}
return pt;
}
public static void ManageDrawMatrix (SKCanvas canvas, int width, int height)
{
var size = ((float)height > width ? width : height) * 0.5f;
var center = new SKPoint ((width - size) / 2f, (height - size) / 2f);
// draw these at specific locations
var leftRect = SKRect.Create (center.X - size / 2f, center.Y, size, size);
var rightRect = SKRect.Create (center.X + size / 2f, center.Y, size, size);
// draw this at the current location / transformation
var rotatedRect = SKRect.Create (0f, 0f, size, size);
using (var paint = new SKPaint ()) {
paint.IsAntialias = true;
canvas.Clear (XamPurple);
// draw
paint.Color = XamDkBlue;
canvas.DrawRect (leftRect, paint);
// save
canvas.Save();
// transform
canvas.Translate (width / 2f, center.Y);
canvas.RotateDegrees (45);
// draw
paint.Color = XamGreen;
canvas.DrawRect (rotatedRect, paint);
// undo transform / restore
canvas.Restore();
// draw
paint.Color = XamLtBlue;
canvas.DrawRect (rightRect, paint);
}
}
private static void DrawPointWithVectorStyle(SKCanvas canvas, VectorStyle vectorStyle,
Point destination, SymbolType symbolType = SymbolType.Ellipse)
{
canvas.Save();
canvas.Translate((float)destination.X, (float)destination.Y);
DrawPointWithVectorStyle(canvas, vectorStyle, symbolType);
canvas.Restore();
}
