Qt Widgets: Implementing a Minimap with Viewport Indicator

[Anirudh]

I’m working on a design tool built with Qt Widgets. I want to add a minimap widget that shows the overall layout of the design. As the user zooms or pans the main view, the minimap should update accordingly and display a red rectangle indicating the current viewport.

If anyone has implemented something similar or can suggest an approach, examples, or relevant Qt classes to look into, I’d really appreciate the help.

[GrecKo]

Maybe with a custom QGraphicsEffect calling drawSource with a scaled/translated QPainter.

Another solution would be to use QWidget::grab() periodically to get a QPixmap of the widget and overlaying that on top of it.

For potential future readers looking for the minimap keyword: In Qt Quick it's pretty easy to do so with just a scaled down ShaderEffectSource.