public void DrawPath(IEnumerable <PathOp> ops, Pen pen = null, Brush brush = null)
{
if (pen == null && brush == null)
{
return;
}
using (var path = new global::Android.Graphics.Path()) {
var bb = new BoundingBoxBuilder();
Point?prevPoint = null;
foreach (var op in ops)
{
var mt = op as MoveTo;
if (mt != null)
{
var p = mt.Point;
path.MoveTo((float)p.X, (float)p.Y);
bb.Add(p);
prevPoint = p;
continue;
}
var lt = op as LineTo;
if (lt != null)
{
var p = lt.Point;
path.LineTo((float)p.X, (float)p.Y);
bb.Add(p);
prevPoint = p;
continue;
}
var at = op as ArcTo;
if (at != null)
{
var p = at.Point;
if (!prevPoint.HasValue)
{
throw new NotSupportedException("Cannot begin path with Arc.");
}
var pp = prevPoint.Value;
Point c1, c2;
at.GetCircles(pp, out c1, out c2);
var circleCenter = at.LargeArc ^ !at.SweepClockwise ? c2 : c1;
var rect = new Rect(circleCenter - at.Radius, at.Radius * 2);
var startAngle = Conversions.RadToDeg((float)Math.Atan2(pp.Y - circleCenter.Y, pp.X - circleCenter.X));
var endAngle = Conversions.RadToDeg((float)Math.Atan2(p.Y - circleCenter.Y, p.X - circleCenter.X));
var sweepAngle = endAngle - startAngle;
if (at.SweepClockwise && sweepAngle < 0)
{
// If we want to go CW, sweepAngle needs to be positive
sweepAngle += 360.0f;
}
else if (!at.SweepClockwise && sweepAngle > 0)
{
// If we want to go CCW, sweepAngle needs to be negative
sweepAngle -= 360.0f;
}
path.AddArc(Conversions.GetRectF(rect), startAngle, sweepAngle);
bb.Add(p);
prevPoint = p;
continue;
}
var ct = op as CurveTo;
if (ct != null)
{
var p = ct.Point;
var c1 = ct.Control1;
var c2 = ct.Control2;
path.CubicTo((float)c1.X, (float)c1.Y, (float)c2.X, (float)c2.Y, (float)p.X, (float)p.Y);
bb.Add(p);
bb.Add(c1);
bb.Add(c2);
prevPoint = p;
continue;
}
var cp = op as ClosePath;
if (cp != null)
{
path.Close();
continue;
}
throw new NotSupportedException("Path Op " + op);
}
var frame = bb.BoundingBox;
if (brush != null)
{
var paint = GetBrushPaint(brush, frame);
graphics.DrawPath(path, paint);
}
if (pen != null)
{
var paint = GetPenPaint(pen);
graphics.DrawPath(path, paint);
}
}
}
public void DrawPath(IEnumerable<PathOp> ops, Pen pen = null, Brush brush = null)
{
if (pen == null && brush == null)
return;
using (var path = new global::Android.Graphics.Path ()) {
var bb = new BoundingBoxBuilder ();
Point? prevPoint = null;
foreach (var op in ops) {
var mt = op as MoveTo;
if (mt != null) {
var p = mt.Point;
path.MoveTo ((float)p.X, (float)p.Y);
bb.Add (p);
prevPoint = p;
continue;
}
var lt = op as LineTo;
if (lt != null) {
var p = lt.Point;
path.LineTo ((float)p.X, (float)p.Y);
bb.Add (p);
prevPoint = p;
continue;
}
var at = op as ArcTo;
if (at != null) {
var p = at.Point;
if (!prevPoint.HasValue) {
throw new NotSupportedException("Cannot begin path with Arc.");
}
var pp = prevPoint.Value;
Point c1, c2;
at.GetCircles(pp, out c1, out c2);
var circleCenter = at.LargeArc ^ !at.SweepClockwise ? c2 : c1;
var rect = new Rect(circleCenter - at.Radius, at.Radius * 2);
var startAngle = Conversions.RadToDeg((float)Math.Atan2(pp.Y - circleCenter.Y, pp.X - circleCenter.X));
var endAngle = Conversions.RadToDeg((float)Math.Atan2(p.Y - circleCenter.Y, p.X - circleCenter.X));
var sweepAngle = endAngle - startAngle;
if (at.SweepClockwise && sweepAngle < 0) {
// If we want to go CW, sweepAngle needs to be positive
sweepAngle += 360.0f;
}
else if (!at.SweepClockwise && sweepAngle > 0) {
// If we want to go CCW, sweepAngle needs to be negative
sweepAngle -= 360.0f;
}
path.AddArc(Conversions.GetRectF(rect), startAngle, sweepAngle);
bb.Add (p);
prevPoint = p;
continue;
}
var ct = op as CurveTo;
if (ct != null) {
var p = ct.Point;
var c1 = ct.Control1;
var c2 = ct.Control2;
path.CubicTo ((float)c1.X, (float)c1.Y, (float)c2.X, (float)c2.Y, (float)p.X, (float)p.Y);
bb.Add (p);
bb.Add (c1);
bb.Add (c2);
prevPoint = p;
continue;
}
var cp = op as ClosePath;
if (cp != null) {
path.Close ();
continue;
}
throw new NotSupportedException ("Path Op " + op);
}
var frame = bb.BoundingBox;
if (brush != null) {
var paint = GetBrushPaint (brush, frame);
graphics.DrawPath (path, paint);
}
if (pen != null) {
var paint = GetPenPaint (pen);
graphics.DrawPath (path, paint);
}
}
}
