public float MinLineWidthFactor { get; set; }

Property Value

In GDI and GDI+ (metafiles are drawn in it) it is possible to set line thickness value to 0. This means that the line is always drawn 1 pixel wide regardless to the screen resolution and image size. But in WPF this is not possible - this is the reason for MinLineWidthFactor property.

When a line with thickness value 0 is read from metafile, ReaderWmf uses MinLineWidthFactor value to create a WPF's StrokeThickness value. The used value can be read from UsedMinLineWidthFactor property.

The default value of MinLineWidthFactor is 0, which means that ReaderWmf tries to find a StrokeThickness value that is based on the size of metafile. But this value is not always good. If the used StrokeThickness is to big, the lines are to wide which covers some details. If lines are too thin, the image is hardly visible.

To manually control the StrokeThickness, set the value to MinLineWidthFactor property to any value bigger than 0.

NOTE:
MinLineWidthFactor must be set before reading metafile.

Reference