ScaleRangeDisplayFilter Class

Member Function Documentation

ScaleRangeDisplayFilter::ScaleRangeDisplayFilter(const QString &name, const QString &whereClause, double minScale, double maxScale, QObject *parent = nullptr)

Creates a new ScaleRangeDisplayFilter with the specified name, where clause, and scale range.

• name - A descriptive name for this display filter.
• whereClause - A SQL expression that defines which features are rendered.
• minScale - The minimum scale at which this display filter is applied. If MapView::mapScale or Viewpoint::targetScale is less than or equal this value, the DisplayFilter will be applied. This value should be greater than maxScale. A value of 0 indicates this display filter is applied without an upper limit.
• maxScale - The maximum scale at which this display filter is applied. If MapView::mapScale or Viewpoint::targetScale is greater than or equal this value, the DisplayFilter will be applied. This value should be less than minScale. A value of 0 indicates this display filter is applied without a lower limit.
• parent - The optional parent QObject.

A maxScale greater than the minScale will create an invalid scale display filter.

[override virtual] ScaleRangeDisplayFilter::~ScaleRangeDisplayFilter()

Destructor.

double ScaleRangeDisplayFilter::maxScale() const

Returns the maximum scale at which this display filter is applied.

This display filter is only applied when zoomed further out than the maximum scale. Set this property to allow current scale of the map to determine when this display filter is applied. A value of 0 indicates this display filter is applied without an upper limit. The default value is 0.

See also setMaxScale().

double ScaleRangeDisplayFilter::minScale() const

Returns the minimum scale at which this display filter is applied.

This display filter is only applied when zoomed further in than the minimum scale. Set this property to allow current scale of the map to determine when this display filter is applied. A value of 0 indicates this display filter is applied without a lower limit. The default value is 0.

See also setMinScale().

void ScaleRangeDisplayFilter::setMaxScale(double maxScale)

Sets the maxScale to maxScale.

See also maxScale.

void ScaleRangeDisplayFilter::setMinScale(double minScale)

Sets the minScale to minScale.

See also minScale.