A few releases ago a bug fix was implemented which forced conversions
of multi-layer sources. This was a valid bug fix, but the consequence
was that any algorithm using this api with a source file containing
multiple layers (e.g. gpkg) performed a complete copy of the target
layer to a new file, severely impacting performance.
This commit adds new API to retrieve a compatible layer path in the
case when an algorithm CAN correctly handle specific target layer names.
In this case, the forced copy of the source layer is avoided when
using multi-layer inputs like geopackage.
to have a file filter string defined
Previously only an extension was settable, which prevented use when
multiple extension types are possible. A file filter string allows
for flexible file selection instead.
which will be available to a parameter when it is evaluated.
Specifying variables via this method is for metadata purposes only.
It is the algorithm's responsibility to correctly set the value of
these additional variables in all expression context used when evaluating
the parameter, in whichever way is appropriate for that particular variable.
This adds a new parameter type specifically for map scales,
QgsProcessingParameterScale. The values are evaluated using
self.parameterAsDouble, which returns the map scale
denominator (matching the standard in other parts of the
QGIS API).
Scale parameters are displayed to users using the standard
QgsScaleWidget, which includes the combo box of predefined
scales and a shortcut button to match the current map scale.
For the c++ api dox this expands to "\c nullptr" (the
\c directive indicates a code literal value), and for sipify/Python
it expands to ``None`` (`` is sphinx annotation for literal values)
Makes for nicer dox for both c++ and Python!
This adds a new available parameter type for processing algorithms,
QgsProcessingParameterAuthConfig, allowing selection from available
authentication configurations (and creation of new ones).
It allows creation of processing algorithm which can fully take
advantage of QGIS' mature authentication handling, avoiding the
need to use insecure string parameters for users to input
sensitive logon credentials.
QgsProcessingParameterAuthConfig parameters are evaluated using
QgsProcessingAlgorithm.parameterAsString(), which returns the
selected authentication configuration ID.
to show in numeric/distance widgets
E.g. to only show 2 decimal places:
# only show two decimal places in parameter's widgets, not 6:
param.setMetadata( {'widget_wrapper':
{ 'decimals': 2 }
})
