def read_settings(self):
        """Set the IF state from QSettings."""
        extent = setting('user_extent', None, str)
        if extent:
            extent = QgsGeometry.fromWkt(extent)
            if not extent.isGeosValid():
                extent = None

        crs = setting('user_extent_crs', None, str)
        if crs:
            crs = QgsCoordinateReferenceSystem(crs)
            if not crs.isValid():
                crs = None

        mode = setting('analysis_extents_mode', HAZARD_EXPOSURE_VIEW)
        if crs and extent and mode == HAZARD_EXPOSURE_BOUNDINGBOX:
            self.extent.set_user_extent(extent, crs)

        self.extent.show_rubber_bands = setting(
            'showRubberBands', False, bool)

        self.zoom_to_impact_flag = setting('setZoomToImpactFlag', True, bool)

        # whether exposure layer should be hidden after model completes
        self.hide_exposure_flag = setting('setHideExposureFlag', False, bool)
Set the IF state from QSettings.