Direct2D (29) : 简化曲线到直线 - ID2D1Geometry.Simplify()

uses Direct2D, D2D1;

procedure TForm1.FormPaint(Sender: TObject);
var
cvs: TDirect2DCanvas;
iEllipseGeometry: ID2D1EllipseGeometry;
iPathGeometry: ID2D1PathGeometry;
iGeometrySink: ID2D1GeometrySink;
ptCenter: TPoint;
begin
ptCenter := Point(ClientWidth div 2, ClientHeight div 2);
D2DFactory.CreateEllipseGeometry(D2D1Ellipse(ptCenter, ClientWidth/4, ClientHeight/4), iEllipseGeometry);

D2DFactory.CreatePathGeometry(iPathGeometry);
iPathGeometry.Open(iGeometrySink);
iEllipseGeometry.Simplify(
D2D1_GEOMETRY_SIMPLIFICATION_OPTION_LINES,
TD2DMatrix3x2F.Identity,
28, //效果图分别演示了此值是 0、7、28 时的简化效果
iGeometrySink
);
iGeometrySink.Close;

cvs := TDirect2DCanvas.Create(Canvas, ClientRect);
cvs.BeginDraw;
cvs.RenderTarget.Clear(D2D1ColorF(clWhite));
cvs.DrawGeometry(iPathGeometry);
cvs.EndDraw;
cvs.Free;
end;

procedure TForm1.FormResize(Sender: TObject);
begin
Repaint;
end;