Allows creation of an index on an attribute in a layer for faster
attribute based filtering
Support depends on the underlying data provider for the layer
Implements a method in QgsGeometry and a processing algorithm to
calculate the pole of inaccessibility for a surface, which is the
most distant internal point from the boundary of the surface. This function
uses the 'polylabel' algorithm (Vladimir Agafonkin, 2016), which is an iterative
approach guaranteed to find the true pole of inaccessibility within a specified
tolerance. More precise tolerances require more iterations and will take longer
to calculate.
With a new option to prefer to snap to closest point on geometry.
The old behaviour was to prefer to snap to nodes, even if a node
was further from the input geometry than a segment. The new option
allows you to snap geometries to the closest point, regardless
of whether it's a node or segment.
This algorithm updates existing geometries (or creates new
geometries) for input features by use of a QGIS expression. This
allows complex geometry modifications which can utilise all the
flexibility of the QGIS expression engine to manipulate and create
geometries for output features.
This algorithm allows you to extract specific nodes from geometries.
Eg you can extract the first or last node in the geometry.
The algorithm accepts a comma separated list of node indices to
extract, eg 0 = first node, 1 = second node, etc. Negative indices
can be used to extract nodes from the end of the geometry. Eg
-1 = last node, -2 = second last node.
segments shorter than a certain threshold or sharp corners
with an angle exceeding a threshold
Expose the angle threshold to processing smooth algorithm
Also:
- optimise QgsGeometry::smooth for new geometry classes
- Fix smooth does not work with geometries containing Z/M
This change allows users to choose which method to use when running
the simplify geometries algorithm, with choices of the existing
distance based (Douglas Peucker) algorithm, area based (Visvalingam)
algorithm and snap-to-grid.
Visvaligam in particular usually results in more cartographically
pleasing simplification over the standard distance based methods.
