WPF 通过分辨率 计算英寸，去除模糊

Matrix m = PresentationSource.FromVisual(this)
                .CompositionTarget.TransformToDevice;
double dpiFactor = 1/m.M11;
 
Pen scaledPen = new Pen( Brushes.Black, 1 * dpiFactor );

protected override void OnRender(DrawingContext drawingContext)
{
    Pen pen = new Pen(Brushes.Black, 1);
    Rect rect = new Rect(20,20, 50, 60);
 
    double halfPenWidth = pen.Thickness / 2;
 
    // Create a guidelines set
    GuidelineSet guidelines = new GuidelineSet();
    guidelines.GuidelinesX.Add(rect.Left + halfPenWidth);
    guidelines.GuidelinesX.Add(rect.Right + halfPenWidth);
    guidelines.GuidelinesY.Add(rect.Top + halfPenWidth);
    guidelines.GuidelinesY.Add(rect.Bottom + halfPenWidth);
 
    drawingContext.PushGuidelineSet(guidelines);
    drawingContext.DrawRectangle(null, pen, rect);
    drawingContext.Pop();
}

http://www.wpftutorial.net/DrawOnPhysicalDevicePixels.html