Geometria vettore

Aggiungi gli attributi della geometria

Computes geometric properties of the features in a vector layer and includes them in the output layer.

Si genera un nuovo vettore con gli stessi contenuti del livello in ingresso, ma con attributi aggiuntivi contenenti le misure geometriche basate sul SR selezionato.

Gli attributi aggiunti alla tabella dipendono dal tipo di geometria e dimensioni del vettore in ingresso:

  • for point layers: X (xcoord), Y (ycoord), Z (zcoord) coordinates and/or M value (mvalue)

  • for line layers: length and, for the LineString and CompoundCurve geometry types, the feature sinuosity and straight distance (straightdis)

  • for polygon layers: perimeter and area

Menu predefinito: Vettore ‣ Strumenti di Geometria

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Calculate using

CALC_METHOD

[enumeration]

Default: 0

Calculation parameters to use for the geometric properties. One of:

  • 0 — SR del vettore

  • 1 — SR del Progetto

  • 2 — Ellissoidale

Added geom info

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output (input copy with geometry) layer One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Added geom info

OUTPUT

[same as input]

Copy of the input vector layer with the addition of the geometry fields

Raggruppa geometrie

Prende un vettore o una tabella e crea un nuovo livello aggregando gli elementi basati su un’espressione di tipo ID univoco

Gli elementi per cui l’espressione ID univoco restituisce lo stesso valore sono raggruppati insieme.

È possibile raggruppare insieme tutti gli elementi della risorsa usando un valore costante nel parametro ID univoco, ad esempio: NULL.

È anche possibile raggruppare elementi in base a multipli campi usando funzioni Array, ad esempio: Array(«Campo1», «Campo2»).

Le geometrie (se presenti) sono combinate in un’unica geometria multi parte per ogni gruppo. Gli attributi in uscita sono calcolati in base ad ogni definizione di raggruppamento data.

This algorithm allows to use the default aggregates functions of the QGIS Expression engine.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Group by expression

GROUP_BY

[tablefield: any]

Default: “NULL”

Choose the grouping field. If NULL all features will be grouped.

Aggregates

AGGREGATES

[list]

List of output layer field definitions. Example of a field definition:

{“aggregate”: “sum”, “delimiter”: “,”, “input”: “ $area”, “length”: 10, “name”: “totarea”, “precision”: 0, “type”: 6}

By default, the list contains all the fields of the input layer. In the GUI, you can edit these fields and their definitions, and you can also:

  • Click the newAttribute button to add a new field.

  • Click deleteAttribute to delete the selected field.

  • Use arrowUp and arrowDown to change order of the fields.

  • Click clearText to reset to the default (the fields of the input layer).

For each of the fields you’d like to retrieve information from, you need to define the following:

Input expression [expression] (input)

Campo o espressione del vettore in ingresso.

Aggregate function [enumeration] (aggregate)

Function 1 da usare sull’espressione in ingresso per restituire il valore aggregato.

Predefinito: concatena (per stringhe), somma (per dati numerici)

Delimiter [string] (delimiter)

Stringa di testo per separare valori aggregati, per esempio nel caso di concatenazioni.

Predefinito: ,

Output field name [string] (name)

Nome dei campi aggregati nel vettore in uscita. Come opzione predefinita viene mantenuto il nome del campo in ingresso.

Type [enumeration] (type)

Data type of the output field. One of:

  • 1 — Boolean

  • 2 — Integer

  • 4 — Integer64

  • 6 — Double

  • 10 — String

  • 14 — Date

  • 16 — DateTime

Length [number] (length)

Lunghezza del campo in uscita.

Precision [number] (precision)

Precisione del campo in uscita.

Load fields from layer

GUI only

[vector: any]

You can load fields from another layer and use them for the aggregation

Aggregated

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output (aggregate) layer One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Aggregated

OUTPUT

[same as input]

Multigeometry vector layer with the aggregated values

Confine

Restituisce la chiusura del confine combinato della geometria (cioè il confine topologico della geometria)

Only for polygon and line layers.

For polygon geometries , the boundary consists of all the lines making up the rings of the polygon.

../../../../_images/boundary_polygon.png

Boundaries (black dashed line) of the source polygon layer

For lines geometries, the boundaries are their end points.

../../../../_images/boundary_lines.png

Boundary layer (red points) for lines. In yellow a selected feature.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line, polygon]

Input line or polygon vector layer

Boundary

OUTPUT

[vector: point, line]

Default: [Create temporary layer]

Specify the output (boundary) layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Boundary

OUTPUT

[vector: point, line]

Boundaries from the input layer (point for line, and line for polygon)

Perimetri di delimitazione

Questo algoritmo calcola il perimetro di delimitazione (inviluppo) per ciascun elemento in un vettore in ingresso. Sono supportati geometrie poligonali e lineari.

../../../../_images/bounding_box.png

Le linee nere rappresentano i perimetri di delimitazione di ogni poligono dell’elemento

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line, polygon]

Input line or polygon vector layer

Bounds

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output (bounding box) layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Bounds

OUTPUT

[vector: polygon]

Bounding boxes of input layer

Buffer

Calcola un’area di buffer per tutte gli elementi del vettore in ingresso, usando una distanza fissa.

It is possible to use a negative distance for polygon input layers. In this case the buffer will result in a smaller polygon (setback).

../../../../_images/buffer2.png

Buffer (in yellow) of points, line and polygon

checkbox Permette features in-place modification 1

Menu predefinito: Vettore ‣ Strumenti di Geoprocessing

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Distance

DISTANCE

[number dataDefined]

Default: 10.0

Buffer distance (from the boundary of each feature). You can use the Data Defined button on the right to choose a field from which the radius will be calculated. This way you can have different radius for each feature (see Variable distance buffer (Graphical Modeler only)).

Segments

SEGMENTS

[number]

Default: 5

Controlla il numero di segmenti di linea da usare per approssimare un quarto di cerchio quando si creano offset arrotondati.

End cap style

END_CAP_STYLE

[enumeration]

Default: 0

Controls how line endings are handled in the buffer. One of:

  • 0 — Arrotondato

  • 1 — Piatto

  • 2 — Quadrato

../../../../_images/buffer_cap_style.png

Stile testata arrotondato, piatto e quadrato

Join style

JOIN_STYLE

[enumeration]

Predefinito: 0

Specifica se devono essere utilizzati stile di unione di tipo arrotondato, seghettato o smussato quando si esegue l’offset degli angoli in una linea. Le opzioni sono:

  • 0 — Arrotondato

  • 1 — Seghettato

  • 2 — Smussato

Miter limit

MITER_LIMIT

[number]

Default: 2.0

Controls the maximum distance from the offset curve to use when creating a mitered join (only applicable for miter join styles). Minimum: 1.

Dissolve result

DISSOLVE

[boolean]

Default: False

Dissolve the final buffer. If True (checked), overlapping buffers will be dissolved (combined) into a new feature.

../../../../_images/buffer_dissolve1.png

Buffer standard e dissolto

Buffered

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output (buffer) layer. One of:

  • Skip output

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Buffered

OUTPUT

[vector: polygon]

Output (buffer) polygon layer

Centroidi

Creates a new point layer, with points representing the centroids of the geometries of the input layer.

The centroid is a single point representing the barycenter (of all parts) of the feature, so it can be outside the feature borders. But can also be a point on each part of the feature.

The attributes of the points in the output layer are the same as for the original features.

../../../../_images/centroids2.png

The red stars represent the centroids of the features of the input layer.

checkbox Permette features in-place modification 1

Menu predefinito: Vettore ‣ Strumenti di Geometria

Vedi anche

Point on Surface

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Create centroid for each part

ALL_PARTS

[boolean dataDefined]

Default: False

If True (checked), a centroid will be created for each part of the geometry

Centroids

OUTPUT

[vector: point]

Default: [Create temporary layer]

Specify the output (centroid) layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Centroids

OUTPUT

[vector: point]

Output point vector layer (centroids)

Controllo validità

Esegue un controllo di validità delle geometrie del vettore.

The geometries are classified in three groups (valid, invalid and error) and for each group, a vector layer with its features is generated:

  • The Valid output layer contains only the valid features (without topological errors).

  • The Invalid output layer contains all the invalid features found by the algorithm.

  • The Error output layer is a point layer that points to where the invalid features were found.

The attribute tables of the generated layers will contain some additional information («message» for the error layer, «FID» and «_errors» for the invalid layer and only «FID» for the valid layer):

The attribute table of each generated vector layer will contain some additional information (number of errors found and types of error):

../../../../_images/check_validity.png

Left: the input layer. Right: the valid layer (green), the invalid layer (orange)

Menu predefinito: Vettore ‣ Strumenti di Geometria

Vedi anche

Fix geometries and the core plugin Plugin Controllo Geometria

Parametri

Label

Name

Type

Description

Input layer

INPUT_LAYER

[vector: any]

Input vector layer

Method

METHOD

[enumeration]

Default: 2

Method to use to check validity. Options:

  • 0: The one selected in digitizing settings

  • 1: QGIS

  • 2: GEOS

Ignore ring self intersection

IGNORE_RING_SELF_INTERSECTION

[boolean]

Default: False

Ignore self intersecting rings when checking for validity.

Valid output

VALID_OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the vector layer to contain a copy of the valid features of the source layer. One of:

  • Skip output

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

Invalid output

INVALID_OUTPUT

[same as input]

Default: [Create temporary layer]

Vector layer containing copy of the invalid features of the source layer with the field _errors listing the summary of the error(s) found. One of:

  • Skip output

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

Error output

ERROR_OUTPUT

[vector: point]

Default: [Create temporary layer]

Point layer of the exact position of the validity problems detected with the message field describing the error(s) found. One of:

  • Skip output

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Count of errors

ERROR_COUNT

[number]

The number of geometries that caused errors.

Error output

ERROR_OUTPUT

[vector: point]

Vettore puntuale dell’esatta posizione del problema di validità individuato con il campo message che descrive l”/gli errore/i trovato/i.

Count of invalid features

INVALID_COUNT

[number]

The number of invalid geometries.

Invalid output

INVALID_OUTPUT

[same as input]

Vector layer containing copy of the invalid features of the source layer with the field _errors listing the summary of the error(s) found.

Count of valid features

VALID_COUNT

[number]

The number of valid geometries.

Valid output

VALID_OUTPUT

[same as input]

Vector layer containing a copy of the valid features of the source layer.

Types of error messages and their meanings

If the GEOS method is used the following error messages can occur:

Error message

Explanation

Example

Repeated point

This error happens when a given vertex is repeated.

../../../../_images/geos_rep_point.png

Ring self-intersection

This error happens when a geometry touches itself and generates a ring.

../../../../_images/geos_ring_inter.png

Self-intersection

This error happens when a geometry touches itself.

../../../../_images/geos_self_inter.png

Topology validation error

Hole lies outside shell

Holes are nested

Interior is disconnected

Nested shells

This error happens when a polygon geometry is on top of another polygon geometry.

../../../../_images/geos_nest_shell.png

Duplicate rings

This error happens when two rings (exterior or interior) of a polygon geometry are identical

../../../../_images/geos_dupl_rings.png

Too few points in geometry component

Invalid coordinate

For a point geometry, this error happens when the geometry does not have a proper coordinate pair. The coordinate pair does not contain a latitude value and a longitude value in that order.

Ring is not closed


If the QGIS method is used the following error messages can occur:

Error message

Explanation

Example

Segment %1 of ring %2 of polygon %3 intersects segment %4 of ring %5 of polygon %6 at %7

Ring %1 with less than four points

Ring %1 not closed

Line %1 with less than two points

Line %1 contains %n duplicate node(s) at %2

This error happens when consecutive points on a line have the same coordinates.

../../../../_images/geos_rep_point.png

Segments %1 and %2 of line %3 intersect at %4

This error happens when a line self intersects (two segments of the line intersect each other).

../../../../_images/qgis_seg_line_int.png

Ring self-intersection

This error happens when an outer or inner (island) ring / boundary of a polygon geometry intersects itself.

../../../../_images/geos_ring_inter.png

Ring %1 of polygon %2 not in exterior ring

Polygon %1 lies inside polygon %2

This error happens when a part of a MultiPolygon geometry is inside a hole of a MultiPolygon geometry.

../../../../_images/qgis_poliinside_.png

Collect geometries

Takes a vector layer and collects its geometries into new multipart geometries.

One or more attributes can be specified to collect only geometries belonging to the same class (having the same value for the specified attributes), alternatively all geometries can be collected.

All output geometries will be converted to multi geometries, even those with just a single part. This algorithm does not dissolve overlapping geometries - they will be collected together without modifying the shape of each geometry part.

See the “Promote to multipart” or “Aggregate” algorithms for alternative options.

Menu predefinito: Vettore ‣ Strumenti di Geometria

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Unique ID fields

FIELD

[tablefield: any] [list]

Choose one or more attributes to collect the geometries

Collected

OUTPUT

[same as input]

Vector layer with collected geometries

In uscita:

Label

Name

Type

Description

Collected

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer for the collected geometries. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

Concave hull (alpha shapes)

Computes the concave hull of the features in an input point layer.

../../../../_images/concave_hull_threshold.png

Concave hulls with different thresholds (0.3, 0.6, 0.9)

Parametri

Label

Name

Type

Description

Input point layer

INPUT

[vector: point]

Input point vector layer

Threshold

ALPHA

[number]

Default: 0.3

Number from 0 (maximum concave hull) to 1 (convex hull).

Allow holes

HOLES

[boolean]

Default: True

Choose whether to allow holes in the final concave hull

Split multipart geometry into singlepart geometries

NO_MULTIGEOMETRY

[boolean]

Default: True

Check if you want to have singlepart geometries instead of multipart ones.

Concave hull

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Concave hull

OUTPUT

[vector: polygon]

The output vector layer

Concave hull (k-nearest neighbor)

This algorithm generates a concave hull polygon from a set of points. If the input layer is a line or polygon layer, it will use the vertices.

The number of neighbors to consider determines the concaveness of the output polygon. A lower number will result in a concave hull that follows the points very closely, while a higher number will have a smoother shape. The minimum number of neighbor points to consider is 3. A value equal to or greater than the number of points will result in a convex hull.

If a field is selected, the algorithm will group the features in the input layer using unique values in that field and generate individual polygons in the output layer for each group.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Number of neighboring points to consider (a lower number is more concave, a higher number is smoother)

KNEIGHBORS

[number]

Default: 3

Determines the concaveness of the output polygon. A small number will result in a concave hull that follows the points very closely, while a high number will make the polygon look more like the convex hull (if the number is equal to or larger than the number of features, the result will be the convex hull). Minimum value: 3.

Field

Optional

FIELD

[tablefield: any]

Default: None

If specified, one concave hull polygon is generated for each unique value of the field (by selecting features using this value).

Concave hull

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Concave hull

OUTPUT

[vector: polygon]

The output vector layer

Convert geometry type

Generates a new layer based on an existing one, with a different type of geometry.

Not all conversions are possible. For instance, a line layer can be converted to a point layer, but a point layer cannot be converted to a line layer.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

New geometry type

TYPE

[enumeration]

Default: 0

Geometry type to apply to the output features. One of:

  • 0 — Centroids

  • 1 — Nodes

  • 2 — Linestrings

  • 3 — Multilinestrings

  • 4 — Polygons

Nota

The available conversion types depend on the input layer and the conversion chosen: e.g. it is not possible to convert a point to a line.

Converted

OUTPUT

[vector: any]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Converted

OUTPUT

[vector: any]

Output vector layer - the type depends on the parameters

Convex hull

Calculates the convex hull for each feature in an input layer.

See the “Minimum bounding geometry” algorithm for a convex hull calculation which covers the whole layer or grouped subsets of features.

../../../../_images/convex_hull1.png

Black lines identify the convex hull for each layer feature

checkbox Permette features in-place modification 1

Menu predefinito: Vettore ‣ Strumenti di Geoprocessing

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Convex hull

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Convex hull

OUTPUT

[vector: polygon]

The output (convex hull) vector layer

Create layer from extent

Creates a new vector layer that contains a single feature with geometry matching the extent of the input layer.

It can be used in models to convert a literal extent (xmin, xmax, ymin, ymax format) into a layer which can be used for other algorithms which require a layer based input.

Parametri

Label

Name

Type

Description

Extent (xmin, xmax, ymin, ymax)

INPUT

[extent]

Input extent

Extent

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Extent

OUTPUT

[vector: polygon]

The output (extent) vector layer

Create wedge buffers

Creates wedge shaped buffers from input points.

../../../../_images/wedge_buffers.png

Wedge buffers

The native output from this algorithm are CurvePolygon geometries, but these may be automatically segmentized to Polygons depending on the output format.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: point]

Input point vector layer

Azimuth (degrees from North)

AZIMUTH

[number dataDefined]

Default: 0.0

Angle (in degrees) as the middle value of the wedge

Wedge width (in degrees)

WIDTH

[number dataDefined]

Default: 45.0

Width (in degrees) of the buffer. The wedge will extend to half of the angular width either side of the azimuth direction.

../../../../_images/wedge_buffers_azimuth_width.png

Azimuth and width values of the wedge buffer

Outer radius

OUTER_RADIUS

[number dataDefined]

Default: 1.0

The outer size (length) of the wedge: the size is meant from the source point to the edge of the wedge shape.

Inner radius

Optional

INNER_RADIUS

[number dataDefined]

Default: 0.0

Inner radius value. If 0 the wedge will begin from the source point.

Buffers

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Buffers

OUTPUT

[vector: polygon]

The output (wedge buffer) vector layer

Delaunay triangulation

Creates a polygon layer with the Delaunay triangulation corresponding to the input point layer.

../../../../_images/delaunay1.png

Delaunay triangulation on points

Menu predefinito: Vettore ‣ Strumenti di Geometria

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: point]

Input point vector layer

Delaunay triangulation

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Delaunay triangulation

OUTPUT

[vector: polygon]

The output (Delaunay triangulation) vector layer

../../../../_images/delete_holes.png

Before and after the cleaning

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: polygon]

Input polygon vector layer

Remove holes with area less than

Optional

MIN_AREA

[number dataDefined]

Default: 0.0

Only holes with an area less than this threshold will be deleted. If 0.0 is added, all the holes will be deleted.

Cleaned

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Cleaned

OUTPUT

[same as input]

The output (cleaned) vector layer

Delete holes

Takes a polygon layer and removes holes in polygons. It creates a new vector layer in which polygons with holes have been replaced by polygons with only their external ring. Attributes are not modified.

An optional minimum area parameter allows removing only holes which are smaller than a specified area threshold. Leaving this parameter at 0.0 results in all holes being removed.

../../../../_images/delete_holes.png

Before and after the cleaning

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: polygon]

Input polygon vector layer

Remove holes with area less than

Optional

MIN_AREA

[number dataDefined]

Default: 0.0

Only holes with an area less than this threshold will be deleted. With a value of 0.0, all the holes will be deleted.

Cleaned

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Cleaned

OUTPUT

[same as input]

The output (cleaned) vector layer

Densify by count

Takes a polygon or line layer and generates a new one in which the geometries have a larger number of vertices than the original one.

If the geometries have Z or M values present then these will be linearly interpolated at the added vertices.

The number of new vertices to add to each segment is specified as an input parameter.

../../../../_images/densify_geometry.png

Red points show the vertices before and after the densify

checkbox Permette features in-place modification 1

Menu predefinito: Vettore ‣ Strumenti di Geometria

Vedi anche

Densify by interval

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line, polygon]

Input line or polygon vector layer

Vertices to add

VERTICES

[number]

Default: 1

Number of vertices to add to each segment

Densified

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Densified

OUTPUT

[same as input]

The output (densified) vector layer

Densify by interval

Takes a polygon or line layer and generates a new one in which the geometries have a larger number of vertices than the original one.

The geometries are densified by adding regularly placed extra vertices inside each segment so that the maximum distance between any two vertices does not exceed the specified distance.

If the geometries have Z or M values present then these will be linearly interpolated at the added vertices.

Example

Specifying a distance of 3 would cause the segment [0 0] -> [10 0] to be converted to [0 0] -> [2.5 0] -> [5 0] -> [7.5 0] -> [10 0], since 3 extra vertices are required on the segment and spacing these at 2.5 increments allows them to be evenly spaced over the segment.

../../../../_images/densify_geometry_interval.png

Densify geometry at a given interval

checkbox Permette features in-place modification 1

Vedi anche

Densify by count

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line, polygon]

Input line or polygon vector layer

Interval between vertices to add

INTERVAL

[number dataDefined]

Default: 1.0

Maximum distance between two consecutive vertices

Densified

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Densified

OUTPUT

[same as input]

The output (densified) vector layer

Dissolve

Takes a vector layer and combines its features into new features. One or more attributes can be specified to dissolve features belonging to the same class (having the same value for the specified attributes), alternatively all features can be dissolved to a single feature.

All output geometries will be converted to multi geometries. In case the input is a polygon layer, common boundaries of adjacent polygons being dissolved will get erased.

The resulting attribute table will have the same fields as the input layer. The values in the output layer’s fields are the ones of the first input feature that happens to be processed.

../../../../_images/dissolve1.png

Dissolve the polygon layer on a common attribute

Menu predefinito: Vettore ‣ Strumenti di Geoprocessing

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Dissolve field(s)

Optional

FIELD

[tablefield: any] [list]

Default: []

Features having the same value for the selected field(s) will be replaced with a single one and their geometries are merged.

If no field is provided then all the features are dissolved, resulting in a single (multipart) feature.

*Dissolved

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Dissolved

OUTPUT

[same as input]

The output vector layer with dissolved geometries

Drape (set Z value from raster)

Uses values sampled from a band within a raster layer to set the Z value for every overlapping vertex in the feature geometry. The raster values can optionally be scaled by a preset amount.

If Z values already exist in the layer, they will be overwritten with the new value. If no Z values exist, the geometry will be upgraded to include the Z dimension.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Raster layer

RASTER

[raster]

Raster layer with Z values

Band number

BAND

[raster band]

Default: 1

The raster band to take the Z values from

Value for nodata or non-intersecting vertices

NODATA

[number dataDefined]

Default: 0

Value to use in case the vertex does not intersect (a valid pixel of) the raster

Scale factor

SCALE

[number dataDefined]

Default: 1.0

Scaling value: the band values are multiplied by this value.

Updated

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer (with Z values from the raster layer). One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Updated

OUTPUT

[same as input]

The output vector layer with Z values from the raster layer

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer with M or Z values

Drop M Values

DROP_M_VALUES

[boolean]

Default: False

Removes the M values from the geometries

Drop Z Values

DROP_Z_VALUES

[boolean]

Default: False

Removes the Z values from the geometries

Z/M Dropped

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Z/M Dropped

OUTPUT

[same as input]

The output vector layer (identical to the input layer, except that the M and/or Z dimensions have been removed from the geometries).

Drop M/Z values

Removes M (measure) or Z (altitude) values from input geometries.

Vedi anche

Set M value, Set Z value

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer with M or Z values

Drop M Values

DROP_M_VALUES

[boolean]

Default: False

Removes the M values from the geometries

Drop Z Values

DROP_Z_VALUES

[boolean]

Default: False

Removes the Z values from the geometries

Z/M Dropped

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Z/M Dropped

OUTPUT

[same as input]

The output vector layer (identical to the input layer, except that the M and/or Z dimensions have been removed from the geometries).

Eliminate selected polygons

Combines selected polygons of the input layer with certain adjacent polygons by erasing their common boundary. The adjacent polygon can be either the one with the largest or smallest area or the one sharing the largest common boundary with the polygon to be eliminated.

Eliminate is normally used to get rid of sliver polygons, i.e. tiny polygons that are a result of polygon intersection processes where boundaries of the inputs are similar but not identical.

Menu predefinito: Vettore ‣ Strumenti di Geoprocessing

Vedi anche

Fix geometries

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: polygon]

Input polygon vector layer

Merge selection with the neighboring polygon with the

MODE

[enumeration]

Default: None

Choose the parameter to use in order to get rid of the selected polygons:

  • 0 — Largest Area

  • 1 — Smallest Area

  • 2 — Largest Common Boundary

Eliminated

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Eliminated

OUTPUT

[vector: polygon]

The output polygon vector layer.

Explode lines

Takes a lines layer and creates a new one in which each line layer is replaced by a set of lines representing the segments in the original line.

Each line in the resulting layer contains only a start and an end point, with no intermediate vertices between them.

../../../../_images/explode_lines.png

The original line layer and the exploded one

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line]

Input line vector layer

Exploded

OUTPUT

[vector: line]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Exploded

OUTPUT

[vector: line]

The output line vector layer with features representing each segment of the input layer.

Extend lines

Extends line geometry by a specified amount at the start and end of the line.

Lines are extended using the bearing of the first and last segment in the line.

../../../../_images/extend_lines.png

The red dashes represent the initial and final extension of the original layer

checkbox Permette features in-place modification 1

Vedi anche

Line substring

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line]

Input line vector layer

Start distance

START_DISTANCE

[number dataDefined]

Distance by which to extend the first segment of the line (starting point)

End distance

END_DISTANCE

[number dataDefined]

Distance by which to extend the last segment of the line (ending point)

Extended

OUTPUT

[vector: line]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Extended

OUTPUT

[vector: line]

The output (extended) line vector layer.

Extract specific vertices

Takes a vector layer and generates a point layer with points representing specific vertices in the input geometries.

For instance, this algorithm can be used to extract the first or last vertices in the geometry. The attributes associated to each point are the same ones associated to the feature that the vertex belongs to.

The vertex indices parameter accepts a comma separated string specifying the indices of the vertices to extract. The first vertex corresponds to an index of 0, the second vertex has an index of 1, etc. Negative indices can be used to find vertices at the end of the geometry, e.g., an index of -1 corresponds to the last vertex, -2 corresponds to the second last vertex, etc.

Additional fields are added to the vertices indicating the specific vertex position (e.g., 0, -1, etc), the original vertex index, the vertex’s part and its index within the part (as well as its ring for polygons), distance along the original geometry and bisector angle of vertex for the original geometry.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Vertex indices

VERTICES

[string]

Default: “0”

Comma-separated string of the indices of the vertices to extract.

Vertices

OUTPUT

[vector: point]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Vertices

OUTPUT

[vector: point]

The output (point) vector layer containing the specified vertices from the input layer geometries.

Extract vertices

Takes a vector layer and generates a point layer with points representing the vertices in the input geometries.

The attributes associated to each point are the same ones associated to the feature that the vertex belongs to.

Additional fields are added to the vertices indicating the vertex index (beginning at 0), the feature’s part and its index within the part (as well as its ring for polygons), distance along original geometry and bisector angle of vertex for original geometry.

../../../../_images/extract_nodes1.png

Vertices extracted for line and polygon layer

Menu predefinito: Vettore ‣ Strumenti di Geometria

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Vertices

OUTPUT

[vector: point]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Vertices

OUTPUT

[vector: point]

The output (point) vector layer containing the vertices from the input layer geometries.

Filter vertices by M value

Filters away vertices based on their M value, returning geometries with only vertex points that have a M value greater than or equal to the specified minimum value and/or less than or equal to the maximum value.

If the minimum value is not specified then only the maximum value is tested, and similarly if the maximum value is not specified then only the minimum value is tested.

../../../../_images/filter_zm.png

The red line represents the black line with only vertices whose M value is <=10.

Nota

Depending on the input geometry attributes and the filters used, the resultant geometries created by this algorithm may no longer be valid.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line, polygon]

Input line or polygon vector layer to remove vertices from

Minimum

Optional

MIN

[number dataDefined]

Default: Not set

Minimum of M values allowed

Maximum

Optional

MAX

[number dataDefined]

Default: Not set

Maximum of M values allowed

Filtered

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Filtered

OUTPUT

[same as input]

The output vector layer of features with only the filtered vertices.

Filter vertices by Z value

Filters away vertices based on their Z value, returning geometries with only vertex points that have a Z value greater than or equal to the specified minimum value and/or less than or equal to the maximum value.

If the minimum value is not specified then only the maximum value is tested, and similarly if the maximum value is not specified then only the minimum value is tested.

../../../../_images/filter_zm.png

The red line represents the black line with only vertices whose Z value is <=10.

Nota

Depending on the input geometry attributes and the filters used, the resultant geometries created by this algorithm may no longer be valid. You may need to run the Fix geometries algorithm to ensure their validity.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line, polygon]

Input line or polygon vector layer to remove vertices from

Minimum

Optional

MIN

[number dataDefined]

Default: Not set

Minimum of Z values allowed

Maximum

Optional

MAX

[number dataDefined]

Default: Not set

Maximum of Z values allowed

Filtered

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Filtered

OUTPUT

[same as input]

The output vector layer of features with only the filtered vertices.

Fix geometries

Attempts to create a valid representation of a given invalid geometry without losing any of the input vertices. Already valid geometries are returned without further intervention. Always outputs multi-geometry layer.

Nota

M values will be dropped from the output.

checkbox Permette features in-place modification 1

Vedi anche

Controllo validità

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Fixed geometries

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Fixed geometries

OUTPUT

[same as input]

The output vector layer with fixed geometries.

Geometry by expression

Updates existing geometries (or creates new geometries) for input features by use of a QGIS expression.

This allows complex geometry modifications which can utilize all the flexibility of the QGIS expression engine to manipulate and create geometries for output features.

For help with QGIS expression functions, see the inbuilt help available in the expression builder.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Output geometry type

OUTPUT_GEOMETRY

[enumeration]

Default: 0

The output geometry strongly depends on the expression: for instance, if you create a buffer the geometry type has to be polygon. One of:

  • 0 — Polygon

  • 1 — Line

  • 2 — Point

Output geometry has z values

WITH_Z

[boolean]

Default: False

Choose if the output geometry should include the Z dimension

Output geometry has m values

WITH_M

[boolean]

Default: False

Choose if the output geometry should include the M dimension

Geometry expression

EXPRESSION

[expression]

Default: “$geometry”

Add the geometry expression you want to use. You can use the button to open the Expression Dialog. The dialog lists all the relevant expressions, together with their help and guide.

Modified geometry

OUTPUT

[vector: any]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Modified geometry

OUTPUT

[vector: any]

The output vector layer

Interpolate point on line

Creates a point geometry interpolated at a set distance along line or curve geometries.

Z and M values are linearly interpolated from existing values.

If a multipart geometry is encountered, only the first part is considered when calculating the substring.

If the specified distance is greater than the input feature’s length, the resultant feature will have a null geometry.

../../../../_images/interpolated_point.png

Interpolated point at 500m of the beginning of the line

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line, polygon]

Input line or polygon vector layer

Distance

DISTANCE

[number dataDefined]

Default: 0.0

Distance from the beginning of the line

Interpolated points

OUTPUT

[vector: point]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Interpolated points

OUTPUT

[vector: point]

The output point vector layer with features at a set distance along the line or polygon boundary

Keep N biggest parts

Takes a layer with polygons or multipolygons and returns a new layer in which only the n largest polygons of each multipolygon feature are kept. If a feature has n or fewer parts, the feature will just be copied.

../../../../_images/n_biggest.png

Clockwise from top left: original multipart feature, one, two and three biggest parts kept

Parametri

Label

Name

Type

Description

Polygons

INPUT

[vector: polygon]

Input polygon vector layer

Parts to keep

PARTS

[number]

Default: 1

Number of parts to keep. If 1, only the biggest part of the feature will be kept.

Parts

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output polygon vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Parts

OUTPUT

[vector: polygon]

The output polygon vector layer with the N biggest parts of each feature

Line substring

Returns the portion of a line (or curve) which falls between the specified start and end distances (measured from the beginning of the line).

Z and M values are linearly interpolated from existing values.

If a multipart geometry is encountered, only the first part is considered when calculating the substring.

../../../../_images/substring.png

Substring line with starting distance set at 0 meters and the ending distance at 250 meters.

checkbox Permette features in-place modification 1

Vedi anche

Extend lines

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line]

Input line vector layer

Start distance

START_DISTANCE

[number dataDefined]

Distance along the input line to the start point of the output feature

End distance

END_DISTANCE

[number dataDefined]

Distance along the input line to the end point of the output feature

Substring

OUTPUT

[vector: line]

Default: [Create temporary layer]

Specify the output line vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Substring

OUTPUT

[vector: line]

The output line vector layer.

Lines to polygons

Generates a polygon layer using as polygon rings the lines from an input line layer.

The attribute table of the output layer is the same as the one from of the input line layer.

Menu predefinito: Vettore ‣ Strumenti di Geometria

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line]

Input line vector layer

Polygons

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output polygon vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Polygons

OUTPUT

[vector: polygon]

The output polygon vector layer.

Merge lines

Joins all connected parts of MultiLineString geometries into single LineString geometries.

If any parts of the input MultiLineString geometries are not connected, the resultant geometry will be a MultiLineString containing any lines which could be merged and any non-connected line parts.

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line]

Input line vector layer

Merged

OUTPUT

[vector: line]

Default: [Create temporary layer]

Specify the output line vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Merged

OUTPUT

[vector: line]

The output (merged) line vector layer.

Minimum bounding geometry

Creates geometries which enclose the features from an input layer. The features can be grouped by a field. The output layer will then contain one feature per group value with a geometry (MBB) that covers the geometries of the features with matching value.

The following enclosing geometry types are supported:

  • bounding box (envelope)

  • oriented rectangle

  • circle

  • convex hull

../../../../_images/minimum_bounding.png

Clockwise from top left: envelope, oriented rectangle, circle, convex hull

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Field

Optional

FIELD

[tablefield: any]

Features can be grouped by a field. If set, this causes the output layer to contain one feature per grouped value with a minimal geometry covering only the features with matching values.

Geometry type

TYPE

[enumeration]

Default: 0

Enclosing geometry types. One of:

  • 0 — Envelope (Bounding Box)

  • 1 — Minimum Oriented Rectangle

  • 2 — Minimum Enclosing Circle

  • 3 — Convex Hull

Bounding geometry

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output polygon vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Bounding geometry

OUTPUT

[vector: polygon]

The output (bounding) polygon vector layer.

Minimum enclosing circles

Calculates the minimum enclosing circles of the features in the input layer.

../../../../_images/minimum_enclosing_circles.png

Enclosing circles for each feature

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Number of segment in circles

SEGMENTS

[number]

Default: 72

The number of segment used to approximate a circle. Minimum 8, maximum 100000.

Minimum enclosing circles

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output polygon vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Minimum enclosing circles

OUTPUT

[vector: polygon]

The output polygon vector layer.

Multi-ring buffer (constant distance)

Computes multi-ring (donut) buffer for the features of the input layer, using a fixed or dynamic distance and number of rings.

../../../../_images/multiringbuffer.png

Multi-ring buffer for a line, point and polygon layer

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Number of rings

RINGS

[number dataDefined]

Default: 1

The number of rings. It can be a unique value (same number of rings for all the features) or it can be taken from features data (the number of rings depends on feature values).

Distance between rings

DISTANCE

[number dataDefined]

Default: 1.0

Distance between the rings. It can be a unique value (same distance for all the features) or it can be taken from features data (the distance depends on feature values).

Multi-ring buffer (constant distance)

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output polygon vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Multi-ring buffer (constant distance)

OUTPUT

[vector: polygon]

The output polygon vector layer.

Multipart to singleparts

Splits multipart features in the input layer into singlepart features.

The attributes of the output layer is the same of the original ones but divided into single features.

../../../../_images/multipart.png

Left the multipart source layer and right the single part output result

checkbox Permette features in-place modification 1

Menu predefinito: Vettore ‣ Strumenti di Geometria

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Single parts

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output polygon vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Single parts

OUTPUT

[same as input]

The output vector layer.

Offset lines

Offsets lines by a specified distance. Positive distances will offset lines to the left, and negative distances will offset them to the right.

../../../../_images/offset_lines.png

In blue the source layer, in red the offset one

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line]

Input line vector layer

Distance

DISTANCE

[number dataDefined]

Default: 10.0

Offset distance. You can use the Data Defined button on the right to choose a field from which the radius will be calculated. This way you can have different radius for each feature (see Variable distance buffer (Graphical Modeler only)).

Segments

SEGMENTS

[number]

Default: 8

Controlla il numero di segmenti di linea da usare per approssimare un quarto di cerchio quando si creano offset arrotondati.

Join style

JOIN_STYLE

[enumeration]

Predefinito: 0

Specifica se devono essere utilizzati stile di unione di tipo arrotondato, seghettato o smussato quando si esegue l’offset degli angoli in una linea. Le opzioni sono:

  • 0 — Arrotondato

  • 1 — Seghettato

  • 2 — Smussato

Miter limit

MITER_LIMIT

[number]

Default: 2.0

Controls the maximum distance from the offset curve to use when creating a mitered join (only applicable for miter join styles). Minimum: 1.

Offset

OUTPUT

[vector: line]

Default: [Create temporary layer]

Specify the output (offset) layer. One of:

  • Skip output

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Offset

OUTPUT

[vector: line]

Output (offset) line layer

Oriented minimum bounding box

Calculates the minimum area rotated rectangle for each feature in the input layer.

../../../../_images/oriented_minimum_bounding_box.png

Oriented minimum bounding box

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Bounding boxes

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output polygon vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Bounding boxes

OUTPUT

[vector: polygon]

The output polygon vector layer.

Orthogonalize

Attempts to orthogonalize the geometries of the input line or polygon layer. This process shifts the vertices in the geometries to try to make every angle in the geometry either a right angle or a straight line.

../../../../_images/orthogonize.png

In blue the source layer and in the red orthogonalized result

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line, polygon]

Input line or polygon vector layer

Maximum angle tolerance (degrees)

ANGLE_TOLERANCE

[number]

Default: 15

Specify the maximum deviation from a right angle or straight line a vertex can have for it to be adjusted. Smaller tolerances mean that only vertices which are already closer to right angles will be adjusted, and larger tolerances mean that vertices which deviate further from right angles will also be adjusted.

Maximum algorithm iterations

MAX_ITERATIONS

[number]

Default: 1000

Setting a larger number for the maximum number of iterations will result in a more orthogonal geometry at the cost of extra processing time.

Orthogonalized

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output polygon vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Orthogonalized

OUTPUT

[same as input]

The output polygon vector layer with adjusted angles.

Point on Surface

For each feature of the input layer, returns a point that is guaranteed to lie on the surface of the feature geometry.

checkbox Permette features in-place modification 1

Vedi anche

Centroidi

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Create point on surface for each part

ANGLE_TOLERANCE

[boolean dataDefined]

If checked, a point will be created for each part of the geometry.

Point

OUTPUT

[vector: point]

Default: [Create temporary layer]

Specify the output point vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Point

OUTPUT

[vector: point]

The output point vector layer.

Points along geometry

Creates points at regular intervals along line or polygon geometries. Created points will have new attributes added for the distance along the geometry and the angle of the line at the point.

An optional start and end offset can be specified, which controls how far from the start and end of the geometry the points should be created.

../../../../_images/points_along_line.png

Points created along the source line layer

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line, polygon]

Input line or polygon vector layer

Distance

DISTANCE

[number dataDefined]

Default: 1.0

Distance between two consecutive points along the line

Start offset

START_OFFSET

[number dataDefined]

Default: 0.0

Distance from the beginning of the input line, representing the position of the first point.

End offset

END_OFFSET

[number dataDefined]

Default: 0.0

Distance from the end of the input line, representing the position beyond which no point feature shoud be created.

Interpolated points

OUTPUT

[vector: point]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Interpolated points

OUTPUT

[vector: point]

Point vector layer with features placed along lines or polygon boundaries of the input layer.

Points displacement

Given a distance of proximity, identifies nearby point features and radially distributes them over a circle whose center represents their barycenter. A convenient tool to scatter overlaid features.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: point]

Input point vector layer

Minimum distance to other points

PROXIMITY

[number]

Default: 1.0

Distance below which point features are considered close. Close features are distributed altogether.

Displacement distance

DISTANCE

[number]

Default: 1.0

Radius of the circle on which close features are placed

Horizontal distribution for two point case

HORIZONTAL

[boolean]

Default: False

When only two points are identified as close, aligns them horizontally on the circle instead of vertically.

Displaced

OUTPUT

[vector: point]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Displaced

OUTPUT

[vector: point]

Output point vector layer

Pole of inaccessibility

Calculates the pole of inaccessibility for a polygon layer, which is the most distant internal point from the boundary of the surface.

This algorithm uses the “polylabel” algorithm (Vladimir Agafonkin, 2016), which is an iterative approach guaranteed to find the true pole of inaccessibility within a specified tolerance. A more precise tolerance (lower value) requires more iterations and will take longer to calculate.

The distance from the calculated pole to the polygon boundary will be stored as a new attribute in the output layer.

../../../../_images/pole_inaccessibility.png

Pole of inaccessibility

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: polygon]

Input vector layer

Tolerance

TOLERANCE

[number]

Default: 1.0

Set the tolerance for the calculation

Point

OUTPUT

[vector: point]

Default: [Create temporary layer]

Specify the output polygon vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Point

OUTPUT

[vector: point]

The output point vector layer

Polygonize

Creates a polygon layer whose features boundaries are generated from a line layer of closed features.

../../../../_images/polygonize.png

The yellow polygons generated from the closed lines

Nota

The line layer must have closed shapes in order to be transformed into a polygon.

Vedi anche

Polygons to lines

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line]

Input line vector layer

Keep table structure of line layer

Optional

KEEP_FIELDS

[boolean]

Default: False

Check to copy the original attributes of the input layer

Polygons from lines

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output polygon vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Polygons from lines

OUTPUT

[vector: polygon]

The output polygon vector layer from lines

Polygons to lines

Takes a polygon layer and creates a line layer, with lines representing the boundaries of the polygons in the input layer.

../../../../_images/polygon_to_lines.png

Black lines as the result of the algorithm

Menu predefinito: Vettore ‣ Strumenti di Geometria

Vedi anche

Polygonize

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: polygon]

Input polygon vector layer

Lines

OUTPUT

[vector: line]

Default: [Create temporary layer]

Specify the output line vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Lines

OUTPUT

[vector: line]

The output line vector layer from polygons

Project points (Cartesian)

Projects point geometries by a specified distance and bearing (azimuth).

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: point]

Input point vector layer

Bearing (degrees from North)

BEARING

[number dataDefined]

Default: 0.0

Clockwise angle starting from North, in degree (°) unit

Distance

DISTANCE

[number dataDefined]

Default: 1.0

Distance to offset geometries, in layer units

Projected

OUTPUT

[vector: point]

Default: [Create temporary layer]

Specify the output point vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Projected

OUTPUT

[vector: point]

The output (projected) point vector layer

Promote to multipart

Takes a vector layer with singlepart geometries and generates a new one in which all geometries are multipart.

Input features which are already multipart features will remain unchanged.

This algorithm can be used to force geometries to multipart types in order to be compatible with data providers that require multipart features.

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Multiparts

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output multipart vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Multiparts

OUTPUT

[same as input]

The output multipart vector layer

Rectangles, ovals, diamonds (fixed)

Creates a buffer area for all the features in an input layer with different shape choice.

Parameters can vary depending on the shape chosen.

../../../../_images/rectangles_ovals_diamond.png

Different buffer shapes

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: point]

Input point vector layer

Buffer shape

SHAPE

[enumeration]

The shape to use. One of:

  • 0 — Rectangles

  • 1 — Ovals

  • 2 — Diamonds

Width

WIDTH

[number]

Default: 1.0

Width of the buffer shape

Height

HEIGHT

[number]

Default: 1.0

Height of the buffer shape

Rotation

Optional

ROTATION

[number]

Default: None

Rotation of the buffer shape

Number of segment

SEGMENTS

[number]

Default: 36

Number of segments for a full circle (Ovals shape)

Output

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Output

OUTPUT

[vector: polygon]

The output vector layer (with the buffer shapes)

Rectangles, ovals, diamonds (variable)

Creates a buffer area for all the features in an input layer with different shape choice.

Buffer shape parameters are specified through attribute of the input layer.

../../../../_images/rectangles_ovals_diamond_variable.png

Different buffer shapes with different parameters

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: point]

Input point vector layer

Buffer shape

SHAPE

[enumeration]

Default: 0

The shape to use. One of:

  • 0 — Rectangles

  • 1 — Ovals

  • 2 — Diamonds

Width field

WIDTH

[tablefield: numeric]

Default: First

Width of the buffer shape

Height field

HEIGHT

[tablefield: numeric]

Default: First

Height of the buffer shape

Rotation field

Optional

ROTATION

[tablefield: numeric]

Rotation of the buffer shape

Number of segment

SEGMENTS

[number]

Default: 36

Number of segments for a full circle (Ovals shape)

Output

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Output

OUTPUT

[vector: polygon]

The output vector layer (with the buffer shapes)

Remove duplicate vertices

Removes duplicate vertices from features, wherever removing the vertices does not result in a degenerate geometry.

The tolerance parameter specifies the tolerance for coordinates when determining whether vertices are identical.

By default, Z values are not considered when detecting duplicate vertices. E.g. two vertices with the same X and Y coordinate but different Z values will still be considered duplicate and one will be removed. If the :guilabel;`Use Z Value` parameter is true, then the Z values are also tested and vertices with the same X and Y but different Z will be maintained.

Nota

Duplicate vertices are not tested between different parts of a multipart geometry, e.g. a multipoint geometry with overlapping points will not be changed by this method.

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Tolerance

TOLERANCE

[number dataDefined]

Default: 0.000001

Vertices closer than the specified distance are considered duplicates

Use Z value

USE_Z_VALUE

[boolean dataDefined]

Default: False

If the :guilabel;`Use Z Value` parameter is true, then the Z values are also tested and vertices with the same X and Y but different Z will be maintained.

Cleaned

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Cleaned

OUTPUT

[same as input]

The output vector layer (without duplicate vertices)

Remove null geometries

Removes any features which do not have a geometry from a vector layer.

All other features will be copied unchanged.

The features with null geometries can be saved to a separate layer.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer (with non-NULL geometries)

Non null geometries

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer for the non-NULL geometries. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

Null geometries

NULL_OUTPUT

[same as input]

Default: [Skip output]

Specify the output vector layer for the NULL geometries. One of:

  • Skip Output

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Null geometries

NULL_OUTPUT

[same as input]

The output vector layer (only NULL geometries)

Non null geometries

OUTPUT

[same as input]

The output vector layer (without NULL geometries)

Reverse line direction

Inverts the direction of a line layer.

../../../../_images/reverse_line.png

Before and after the direction inversion

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line]

Input line vector layer

Reversed

OUTPUT

[vector: line]

Default: [Create temporary layer]

Specify the output line vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Reversed

OUTPUT

[vector: line]

The output line vector layer (with reversed lines)

Rotate

Rotates feature geometries by the specified angle clockwise. The rotation occurs around each feature’s centroid, or optionally around a unique preset point.

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Rotation (degrees clockwise)

ANGLE

[number dataDefined]

Default: 0.0

Angle of the rotation in degrees

Rotation anchor point (x, y)

Optional

ANCHOR

[point]

Default: None

X,Y coordinates of the point to rotate the features around. If not set the rotation occurs around each feature’s centroid.

Rotated

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer (with rotated geometries). One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Rotated

OUTPUT

[same as input]

The output vector layer with rotated geometries

Segmentize by maximum angle

Segmentizes a geometry by converting curved sections to linear sections.

The segmentization is performed by specifying the maximum allowed radius angle between vertices on the straightened geometry (e.g the angle of the arc created from the original arc center to consecutive output vertices on the linearized geometry). Non-curved geometries will be retained without change.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line, polygon]

Input line or polygon vector layer

Maximum angle between vertices (degrees)

ANGLE

[number dataDefined]

Default: 5.0

Maximum allowed radius angle between vertices on the straightened geometry

Segmentized

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer (with segmentized geometries). One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Segmentized

OUTPUT

[same as input]

The output vector layer with segmentized geometries

Segmentize by maximum distance

Segmentizes a geometry by converting curved sections to linear sections.

The segmentization is performed by specifying the maximum allowed offset distance between the original curve and the segmentized representation. Non-curved geometries will be retained without change.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line, polygon]

Input line or polygon vector layer

Maximum offset distance

DISTANCE

[number dataDefined]

Default: 1.0

Maximum allowed offset distance between the original curve and the segmentized representation, in the layer units.

Segmentized

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer (with segmentized geometries). One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Segmentized

OUTPUT

[same as input]

The output vector layer with segmentized geometries

Set M value

Sets the M value for geometries in a layer.

If M values already exist in the layer, they will be overwritten with the new value. If no M values exist, the geometry will be upgraded to include M values and the specified value used as the initial M value for all geometries.

Suggerimento

Use the identifyIdentify Features button to check the added M value: the results are available in the Identify Results dialog.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

M Value

M_VALUE

[number dataDefined]

Default: 0.0

M value to assign to the feature geometries

M Added

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

M Added

OUTPUT

[same as input]

The output vector layer (with M values assigned to the geometries)

Set M value from raster

Uses values sampled from a band within a raster layer to set the M value for every overlapping vertex in the feature geometry. The raster values can optionally be scaled by a preset amount.

If M values already exist in the layer, they will be overwritten with the new value. If no M values exist, the geometry will be upgraded to include M values.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Raster layer

RASTER

[raster]

Raster layer with M values

Band number

BAND

[raster band]

Default: 1

The raster band from which the M values are taken

Value for nodata or non-intersecting vertices

NODATA

[number dataDefined] Default: 0.0

Value to use in case the vertex does not intersect (a valid pixel of) the raster

Scale factor

SCALE

[number dataDefined]

Default: 1.0

Scaling value: the band values are multiplied by this value.

Updated

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer (with updated M values). One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Updated

OUTPUT

[same as input]

The output vector layer (with updated M values)

Set Z value

Sets the Z value for geometries in a layer.

If Z values already exist in the layer, they will be overwritten with the new value. If no Z values exist, the geometry will be upgraded to include Z values and the specified value used as the initial Z value for all geometries.

Suggerimento

Use the identifyIdentify Features button to check the added Z value: the results are available in the Identify Results dialog.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Z Value

Z_VALUE

[number dataDefined]

Default: 0.0

Z value to assign to the feature geometries

Z Added

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Z Added

OUTPUT

[same as input]

The output vector layer (with Z values assigned)

Simplify

Simplifies the geometries in a line or polygon layer. It creates a new layer with the same features as the ones in the input layer, but with geometries containing a lower number of vertices.

The algorithm gives a choice of simplification methods, including distance based (the «Douglas-Peucker» algorithm), area based («Visvalingam» algorithm) and snapping geometries to grid.

../../../../_images/simplify_geometries.png

Clockwise from top left: source layer and increasing simplification tolerances

checkbox Permette features in-place modification 1

Menu predefinito: Vettore ‣ Strumenti di Geometria

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line, polygon]

Input line or polygon vector layer

Simplification method

METHOD

[enumeration]

Default: 0

Simplification method. One of:

  • 0 — Distance (Douglas-Peucker)

  • 1 — Snap to grid

  • 2 — Area (Visvalingam)

Tolerance

TOLERANCE

[number dataDefined]

Default: 1.0

Threshold tolerance (in units of the layer): if the distance between two nodes is smaller than the tolerance value, the segment will be simplified and vertices will be removed.

Simplified

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output (simplified) vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Simplified

OUTPUT

[same as input]

The output (simplified) vector layer

Single sided buffer

Computes a buffer on lines by a specified distance on one side of the line only.

Buffer always results in a polygon layer.

../../../../_images/single_side_buffer.png

Left versus right side buffer on the same vector line layer

Vedi anche

Buffer

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Distance

DISTANCE

[number]

Default: 10.0

Buffer distance (from the boundary of each feature).

Side

SIDE

[enumeration]

Which side to create the buffer on. One of:

  • 0 – Left

  • 1 – Right

Segments

SEGMENTS

[number]

Default: 8

Controlla il numero di segmenti di linea da usare per approssimare un quarto di cerchio quando si creano offset arrotondati.

Join style

JOIN_STYLE

[enumeration]

Specifica se devono essere utilizzati stile di unione di tipo arrotondato, seghettato o smussato quando si esegue l’offset degli angoli in una linea. Le opzioni sono:

  • 0 — Arrotondato

  • 1 — Seghettato

  • 2 — Smussato

Miter limit

MITER_LIMIT

[number]

Default: 2.0

Controls the maximum distance from the offset curve to use when creating a mitered join (only applicable for miter join styles). Minimum: 1.0

Buffer

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output (buffer) layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Buffer

OUTPUT

[vector: polygon]

Output (buffer) polygon layer

Smooth

Smooths the geometries in a line or polygon layer. It creates a new layer with the same features as the ones in the input layer, but with geometries containing a higher number of vertices and corners in the geometries smoothed out.

The iterations parameter dictates how many smoothing iterations will be applied to each geometry. A higher number of iterations results in smoother geometries with the cost of greater number of nodes in the geometries.

../../../../_images/smooth_geometry_1.png

Increasing number of iterations causes smoother geometries

The offset parameter controls how «tightly» the smoothed geometries follow the original geometries. Smaller values results in a tighter fit, and larger values will create a looser fit.

../../../../_images/smooth_geometry_2.png

Blue: the input layer. Offset 0.25 gives the red line, while offset 0.50 gives the green line.

The maximum angle parameter can be used to prevent smoothing of nodes with large angles. Any node where the angle of the segments to either side is larger than this will not be smoothed. For example, setting the maximum angle to 90 degrees or lower would preserve right angles in the geometry.

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line, polygon]

Input line or polygon vector layer

Iterations

ITERATIONS

[number dataDefined]

Default: 1

Increasing the number of iterations will give smoother geometries (and more vertices).

Offset

OFFSET

[number dataDefined]

Default: 0.25

Increasing values will move the smoothed lines / boundaries further away from the input lines / booundaries.

Maximum node angle to smooth

MAX_ANGLE

[number dataDefined]

Default: 180.0

Every node below this value will be smoothed

Smoothed

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output (buffer) layer. One of:

  • Skip output

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Smoothed

OUTPUT

[same as input]

Output (smoothed) vector layer

Aggancia geometrie al vettore

Aggancia le geometrie in un vettore con quelle con quelle di un altro o con quelle all’interno dello stesso vettore.

Matching is done based on a tolerance distance, and vertices will be inserted or removed as required to make the geometries match the reference geometries.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Reference layer

REFERENCE_LAYER

[vector: any]

Vector layer to snap to

Tolerance

TOLERANCE

[number]

Default: 10.0

Controlla quanto vicino i vertici in ingresso necessitino di essere alle geometrie del vettore di riferimento prima che siano agganciate. Questa distanza è specificata in unità del livello.

Behavior*

BEHAVIOR

[enumeration]

Default: 0

Snapping can be done to an existing node or a segment (its closest point to the vertex to move). Available snapping options:

  • 0 — Preferenza per allineamento di nodi, inserisci vertici dove richiesti

  • 1 — Preferisci punto più vicino, inserisci vertici addizionali dove richiesti

  • 2 — Preferisci nodi allineati, non aggiungere nuovi vertici

  • 3 — Preferisci punto più vicino, non aggiungere nuovi vertici

  • 4 — Sposta solo i punti finali, preferisci allineare i nodi

  • 5 — Sposta solo i punti finali, preferisci il punto più vicino

  • 6 — Aggancia i punti finali solo a punti finali

  • 7 — Aggancia ai nodi di ancoraggio (solo singolo vettore)

Snapped geometry

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output (buffer) layer. One of:

  • Skip output

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Snapped geometry

OUTPUT

[same as input]

Output (snapped) vector layer

Aggancia punti alla griglia

Modifica le coordinate delle geometrie in un vettore, così che tutti i punti o vertici siano agganciati al più vicino punto di una griglia.

Se una geometria agganciata non può essere calcolata (o è totalmente collassata) la geometria dell’elemento sarà eliminata.

Snapping can be performed on the X, Y, Z or M axis. A grid spacing of 0 for any axis will disable snapping for that axis.

Nota

Snapping to grid may generate an invalid geometry in some corner cases.

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

X Grid Spacing

HSPACING

[number dataDefined]

Default: 1.0

Grid spacing on the X axis

Y Grid Spacing

VSPACING

[number dataDefined]

Default: 1.0

Grid spacing on the Y axis

Z Grid Spacing

ZSPACING

[number dataDefined]

Default: 0.0

Grid spacing on the Z axis

M Grid Spacing

MSPACING

[number dataDefined]

Default: 0.0

Grid spacing on the M axis

Snapped

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output (buffer) layer. One of:

  • Skip output

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Snapped

OUTPUT

[same as input]

Output (snapped) vector layer

Subdivide

Subdivides the geometry. The returned geometry will be a collection containing subdivided parts from the original geometry, where no part has more than the specified maximum number of nodes.

This is useful for dividing a complex geometry into less complex parts, easier to spatially index and faster to perform spatial operations. Curved geometries will be segmentized before subdivision.

../../../../_images/subdivide.png

Left the input layer, middle maximum nodes value is 100 and right maximum value is 200

Nota

Subdividing a geometry can generate geometry parts that may not be valid and may contain self-intersections.

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

The input vector layer

Maximum nodes in parts

MAX_NODES

[number dataDefined]

Default: 256

Maximum number of vertices each new geometry part is allowed to have. Fewer sub-parts for higher values.

Subdivided

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output line vector layer. One of:

  • Skip output

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Subdivided

OUTPUT

[same as input]

Output vector layer

Swap X and Y coordinates

Switches the X and Y coordinate values in input geometries.

It can be used to repair geometries which have accidentally had their latitude and longitude values reversed.

checkbox Permette features in-place modification 1

Vedi anche

Translate, Rotate

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

The input vector layer

Swapped

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output line vector layer. One of:

  • Skip output

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Swapped

OUTPUT

[same as input]

Output (swapped) vector layer

Tapered buffers

Creates tapered buffer along line geometries, using a specified start and end buffer diameter.

../../../../_images/tapered_buffer.png

Tapered buffer example

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line]

Input line vector layer

Start width

START_WIDTH

[number dataDefined]

Default: 0.0

Represents the radius of the buffer applied at the start point of the line feature

End width

END_WIDTH

[number dataDefined]

Default: 0.0

Represents the radius of the buffer applied at the end point of the line feature.

Segments

SEGMENTS

[number dataDefined]

Default: 16

Controlla il numero di segmenti di linea da usare per approssimare un quarto di cerchio quando si creano offset arrotondati.

Buffered

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output (buffer) layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Buffered

OUTPUT

[vector: polygon]

Output (buffer) polygon layer

Mosaicatura

Tassella un vettore poligonale, dividendo le geometrie in triangoli.

Il risultato consiste in geometrie multipoligonali per ogni elemento in ingresso, con ogni multi poligono costituito da poligoni triangolari.

../../../../_images/tessellated.png

Poligono tassellato (destra)

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: polygon]

Input polygon vector layer

Tesselated

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Tesselated

OUTPUT

[vector: polygon]

Output multipolygonZ layer

Transetto

Crea transetti sui vertici per (multi)linee.

Un transetto è una linea orientata da un angolo (predefinito: perpendicolare) ad una polilinea in ingresso (ai vertici).

I campi degli elementi sono restituiti nel transetto con questi nuovi campi:

  • TR_FID: ID of the original feature

  • TR_ID: ID of the transect. Each transect have an unique ID

  • TR_SEGMENT: ID of the segment of the linestring

  • TR_ANGLE: Angle in degrees from the original line at the vertex

  • TR_LENGTH: Lunghezza totale del transetto

  • TR_ORIENT: Lato del transetto (solamente a sinistra o a destra della linea, o entrambi i lati)

../../../../_images/transect.png

La linea rossa tratteggiata rappresenta il transetto del vettore lineare in ingresso.

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line]

Input line vector layer

Length of the transect

LENGTH

[number dataDefined]

Default: 5.0

Length in map unit of the transect

Angle in degrees from the original line at the vertices

ANGLE

[number dataDefined]

Default: 90.0

Change the angle of the transect

Side to create the transect

SIDE

[enumeration]

Scegli il lato del transetto. Le opzioni disponibili sono:

  • 0 — Sinistro

  • 1 — Destro

  • 2 — Entrambi

Transect

OUTPUT

[vector: line]

Default: [Create temporary layer]

Specify the output line layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Transect

OUTPUT

[vector: line]

Output line layer

Translate

Moves the geometries within a layer, by offsetting with a predefined X and Y displacement.

Z and M values present in the geometry can also be translated.

../../../../_images/translate_geometry.png

Dashed lines represent the translated geometry of the input layer

checkbox Permette features in-place modification 1

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Offset distance (x-axis)

DELTA_X

[number dataDefined]

Default: 0.0

Displacement to apply on the X axis

Offset distance (y-axis)

DELTA_Y

[number dataDefined]

Default: 0.0

Displacement to apply on the Y axis

Offset distance (z-axis)

DELTA_Z

[number dataDefined]

Default: 0.0

Displacement to apply on the Z axis

Offset distance (m values)

DELTA_M

[number dataDefined]

Default: 0.0

Displacement to apply on the M axis

Translated

OUTPUT

[same as input]

Default: [Create temporary layer]

Specify the output vector layer. One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Translated

OUTPUT

[same as input]

Output vector layer

Variable distance buffer (Graphical Modeler only)

Computes a buffer area for all the features in an input layer. This algorithm is only available from the Modellatore grafico.

The size of the buffer for a given feature is defined by an attribute, so it allows different features to have different buffer sizes.

Vedi anche

Buffer

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: any]

Input vector layer

Distance field

DISTANCE

[tablefield: numeric]

Attribute for the distance radius of the buffer

Segments

SEGMENTS

[number]

Predefinito: 5

Controlla il numero di segmenti di linea da usare per approssimare un quarto di cerchio quando si creano offset arrotondati.

Dissolve result

DISSOLVE

[boolean]

Predefinito: Falso

Choose to dissolve the final buffer, resulting in a single feature covering all input features.

../../../../_images/buffer_dissolve1.png

Normal and dissolved buffer

End cap style

END_CAP_STYLE

[enumeration]

Controls how line endings are handled in the buffer.

../../../../_images/buffer_cap_style.png

Stile testata arrotondato, piatto e quadrato

Join style

JOIN_STYLE

[enumeration]

Specifies whether round, miter or beveled joins should be used when offsetting corners in a line.

Miter limit

MITER_LIMIT

[number]

Default: 2.0

Only applicable for mitered join styles, and controls the maximum distance from the offset curve to use when creating a mitered join.

In uscita:

Label

Name

Type

Description

Buffer

OUTPUT

[vector: polygon]

Buffer di vettore poligonale.

Variable width buffer (by M value)

Creates variable width buffers along lines, using the M value of the line geometries as the diameter of the buffer at each vertex.

../../../../_images/variable_buffer_m.png

Variable buffer example

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: line]

Input line vector layer

Segments

SEGMENTS

[number dataDefined]

Default: 16

Number of the buffer segments per quarter circle. It can be a unique value (same value for all the features), or it can be taken from features data (the value can depend on feature attributes).

Buffered

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output (buffer) layer One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Buffered

OUTPUT

[vector: polygon]

Variable buffer polygon layer

Poligoni di Voronoi

Takes a point layer and generates a polygon layer containing the Voronoi polygons (known also as Thiessen polygons) corresponding to those input points.

Ogni posizione all’interno di un poligono di Voronoi è più vicino al punto associato che a qualsiasi altro punto.

../../../../_images/voronoi1.png

Poligoni di Voronoi

Menu predefinito: Vettore ‣ Strumenti di Geometria

Parametri

Label

Name

Type

Description

Input layer

INPUT

[vector: point]

Input point vector layer

Buffer region (% of extent)

BUFFER

[number]

Default: 0.0

The extent of the output layer will be this much bigger than the extent of the input layer

Voronoi polygons

OUTPUT

[vector: polygon]

Default: [Create temporary layer]

Specify the output layer (with the Voronoi polygons). One of:

  • Create Temporary Layer (TEMPORARY_OUTPUT)

  • Save to File…

  • Save to Geopackage…

  • Save to PostGIS Table…

The file encoding can also be changed here.

In uscita:

Label

Name

Type

Description

Voronoi polygons

OUTPUT

[vector: polygon]

Voronoi polygons of the input point vector layer