How to use custom ID2D1SimplifiedGeometrySink implementation

[amannan-123]

Hi,
I'm trying to get path segments of Direct2D geometry using this example from MSDN

Here's the class imlpementation:

private class D2D1SimplifiedGeometrySink : ID2D1SimplifiedGeometrySink
{
	private readonly ID2D1RenderTarget renderTarget;

	public D2D1SimplifiedGeometrySink()
	{ }

	public D2D1SimplifiedGeometrySink(ID2D1RenderTarget renderTarget)
	{
		this.renderTarget = renderTarget;
	}

	public void BeginFigure(Vector2 startPoint, FigureBegin figureBegin) { }

	public void EndFigure(FigureEnd figureEnd) { }

	public void Close() { }

	public void SetFillMode(FillMode fillMode)
	{
	}

	public void SetSegmentFlags(PathSegment vertexFlags)
	{
	}

	public void AddLines(Vector2[] points)
	{
		//// Define brushes and text format
		//using ID2D1SolidColorBrush brush = renderTarget.CreateSolidColorBrush(new Color4(0, 1, 0, 0.5f)); // Semi-transparent green
		//using ID2D1SolidColorBrush textBrush = renderTarget.CreateSolidColorBrush(new Color4(0, 0, 0, 1)); // Solid black for text

		//IDWriteFactory dwriteFactory = DWrite.DWriteCreateFactory<IDWriteFactory>(Vortice.DirectWrite.FactoryType.Shared);
		//IDWriteTextFormat textFormat = dwriteFactory.CreateTextFormat(
		//	"Arial", null, FontWeight.Normal, Vortice.DirectWrite.FontStyle.Normal, FontStretch.Normal, 20, "en-us");
		//textFormat.TextAlignment = TextAlignment.Center;
		//textFormat.ParagraphAlignment = ParagraphAlignment.Center;

		//const float rX = 20;
		//const float rY = 20;

		//// iterate over the points
		//foreach (var point in points)
		//{
		//	renderTarget.FillEllipse(new Ellipse(point, rX, rY), brush);
		//	Rect textRect = new(point.X, point.Y, 0, 0);
		//	textRect.Inflate(rX, rY);
		//	int pointNumber = Array.IndexOf(points, point);
		//	renderTarget.DrawText(pointNumber.ToString(), textFormat, textRect, textBrush);
		//}
	}

	public void AddBeziers(BezierSegment[] beziers)
	{
	}

	public void Dispose()
	{
	}
}

I'm using this class as follows:

D2D1SimplifiedGeometrySink sink = new();
geometry.Simplify(GeometrySimplificationOption.Lines, sink);

geometry.Simplify call is throwing this error:
System.AccessViolationException: 'Attempted to read or write protected memory. This is often an indication that other memory is corrupt.'

Can anyone tell me the correct way to do this?

[amerkoleci]

Hi,
Can you try to subclass from CallbackBase as well?

[amannan-123]

That fixed it. Thanks!!