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Custom dash pattern

  • Hi,

    I have a custom dash pattern that I have which i use to draw the outline of a box of variable size. The setting up of the line is as follows:
    @QVector< qreal > dashes;
    qreal space = 6;
    qreal dashWidth = 4;
    dashes << dashWidth << space;

    However when i am zooming using QGraphicsView, the dashes seems "cycle" around the border which i do not want. Is there a way which i remove the "cycling" effect?

  • I doubt this has anything to do with your custom dash pattern. Have you tried it with the standard dash pattern? Does it behave the same?

  • Yes, the standard dash pattern behaves the same

  • I assume this behavior is by design: The length of line segments and gaps is the same regardless of the zoom level.

    However, if you have, for example, a rectangle, the total length of the circumference is different depending on zoom level. If the total line length changes, then the end of the line might show a gap where before it showed a line segment.

    There is no clean solution. If what you want is a dashed line where the dash length changes with the zoom level, you need to do that with the geometry of the graphic object you use, not with a dash pattern.

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