27.1.16. Vector creation

27.1.16.1. Array of offset (parallel) lines 

Creates copies of line features in a layer, by creating multiple offset versions of each feature. Each new version is incrementally offset by a specified distance.

Positive distance will offset lines to the left, and negative distances will offset them to the right.

../../../../_images/offset_lines_array.png — Obr. 27.36 In blue the source layer, in red the offset one

Allows features in-place modification of line features

Viz také

Offset lines, Array of translated features

Parameters

Basic parameters

Label	Název	Type	Popis
Input layer	`INPUT`	[vector: line]	Input line vector layer to use for the offsets.
Number of features to create	`COUNT`	[number ] Default: 10	Number of offset copies to generate for each feature
Offset step distance	`OFFSET`	[number ] Default: 1.0	Distance between two consecutive offset copies
Offset lines	`OUTPUT`	[vector: line] Default: `[Create temporary layer]`	Specify the output line layer with offset features. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… Append to Layer… The file encoding can also be changed here.

Advanced parameters

Label

Název

Type

Popis

Segments

SEGMENTS

[number]

Default: 8

Number of line segments to use to approximate a quarter circle when creating rounded offsets

Join style

JOIN_STYLE

[enumeration]

Default: 0

Specify whether round, miter or beveled joins should be used when offsetting corners in a line. One of:

0 — Round
1 — Miter
2 — Bevel

../../../../_images/buffer_join_style.png — Obr. 27.37 Round, miter, and bevel join styles

Miter limit

MITER_LIMIT

[number]

Default: 2.0

Sets the maximum distance from the offset geometry to use when creating a mitered join as a factor of the offset distance (only applicable for miter join styles). Minimum: 1.0

../../../../_images/buffer_miter_limit.png — Obr. 27.38 A 10m buffer with a limit of 2 and a 10m buffer with a limit of 1

Outputs

Label	Název	Type	Popis
Offset lines	`OUTPUT`	[vector: line]	Output line layer with offset features. The original features are also copied.

Python code

Algorithm ID: native:arrayoffsetlines

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.2. Array of translated features 

Creates copies of features in a layer by creating multiple translated versions of each. Each copy is incrementally displaced by a preset amount in the X, Y and/or Z axis.

M values present in the geometry can also be translated.

../../../../_images/translate_array.png — Obr. 27.39 Input layers in blue tones, output layers with translated features in red tones

Allows features in-place modification of point, line, and polygon features

Viz také

Translate, Array of offset (parallel) lines

Parameters

Label	Název	Type	Popis
Input layer	`INPUT`	[vector: any]	Input vector layer to translate
Number of features to create	`COUNT`	[number ] Default: 10	Number of copies to generate for each feature
Step distance (x-axis)	`DELTA_X`	[number ] Default: 0.0	Displacement to apply on the X axis
Step distance (y-axis)	`DELTA_Y`	[number ] Default: 0.0	Displacement to apply on the Y axis
Step distance (z-axis)	`DELTA_Z`	[number ] Default: 0.0	Displacement to apply on the Z axis
Step distance (m values)	`DELTA_M`	[number ] Default: 0.0	Displacement to apply on M
Translated	`OUTPUT`	[same as input] Default: `[Create temporary layer]`	Output vector layer with translated (moved) copies of the features. The original features are also copied. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… Append to Layer… The file encoding can also be changed here.

Outputs

Label	Název	Type	Popis
Translated	`OUTPUT`	[same as input]	Output vector layer with translated (moved) copies of the features. The original features are also copied.

Python code

Algorithm ID: native:arraytranslatedfeatures

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.3. Create grid 

Creates a vector layer with a grid covering a given extent. Grid cells can have different shapes:

../../../../_images/create_grid.png — Obr. 27.40 Different grid cell shapes

The size of each element in the grid is defined using a horizontal and vertical spacing.

The CRS of the output layer must be defined.

The grid extent and the spacing values must be expressed in the coordinates and units of this CRS.

Default menu: Vector ► Research Tools

Parameters

Label	Název	Type	Popis
Grid type	`TYPE`	[enumeration] Default: 0	Shape of the grid. One of: 0 — Point 1 — Line 2 — Rectangle (polygon) 3 — Diamond (polygon) 4 — Hexagon (polygon)
Grid extent	`EXTENT`	[extent]	Extent of the grid Available methods are: Calculate from layer…: uses extent of a layer loaded in the current project Calculate from layout map…: uses extent of a layout map item in the active project Calculate from bookmark…: uses extent of a saved bookmark Use map canvas extent Draw on canvas: click and drag a rectangle delimiting the area to take into account Enter the coordinates as `xmin, xmax, ymin, ymax`
Horizontal spacing	`HSPACING`	[number] Default: 1.0	Size of a grid cell on the X-axis
Vertical spacing	`VSPACING`	[number] Default: 1.0	Size of a grid cell on the Y-axis
Horizontal overlay	`HOVERLAY`	[number] Default: 0.0	Overlay distance between two consecutive grid cells on the X-axis
Vertical overlay	`VOVERLAY`	[number] Default: 0.0	Overlay distance between two consecutive grid cells on the Y-axis
Grid CRS	`CRS`	[crs] Default: Project CRS	Coordinate reference system to apply to the grid
Grid	`OUTPUT`	[vector: any] Default: `[Create temporary layer]`	Resulting vector grid layer. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.

Outputs

Label	Název	Type	Popis
Grid	`OUTPUT`	[vector: any]	Resulting vector grid layer. The output geometry type (point, line or polygon) depends on the Grid type.

Python code

Algorithm ID: native:creategrid

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.4. Create points layer from table 

Creates points layer from a table with columns that contain coordinates fields.

Besides X and Y coordinates you can also specify Z and M fields.

Parameters

Label	Název	Type	Popis
Input layer	`INPUT`	[vector: any]	Input vector layer or a table.
X field	`XFIELD`	[tablefield: any]	Field containing the X coordinate
Y field	`YFIELD`	[tablefield: any]	Field containing the Y coordinate
Z field Optional	`ZFIELD`	[tablefield: any]	Field containing the Z coordinate
M field Optional	`MFIELD`	[tablefield: any]	Field containing the M value
Target CRS	`TARGET_CRS`	[crs] Default: `EPSG:4326`	Coordinate reference system to use for layer. The provided coordinates are assumed to be compliant.
Points from table	`OUTPUT`	[vector: point] Default: `[Create temporary layer]`	Specify the resulting point layer. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.

Outputs

Label	Název	Type	Popis
Points from table	`OUTPUT`	[vector: point]	The resulting point layer

Python code

Algorithm ID: native:createpointslayerfromtable

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.5. Generate points (pixel centroids) along line 

Generates a point vector layer from an input raster and line layer.

The points correspond to the pixel centroids that intersect the line layer.

../../../../_images/points_centroids.png — Obr. 27.41 Points of the pixel centroids

Parameters

Label

Název

Type

Popis

Raster layer

INPUT_RASTER

[raster]

Input raster layer

Vector layer

INPUT_VECTOR

[vector: line]

Input line vector layer

Points along line

OUTPUT

[vector: point]

Default: [Create temporary layer]

Resulting point layer with pixel centroids. One of:

Create Temporary Layer (TEMPORARY_OUTPUT)
Save to File…
Save to Geopackage…
Save to Database Table…

The file encoding can also be changed here.

Outputs

Label	Název	Type	Popis
Points along line	`OUTPUT`	[vector: point]	Resulting point layer with pixel centroids

Python code

Algorithm ID: qgis:generatepointspixelcentroidsalongline

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.6. Generate points (pixel centroids) inside polygon 

Generates a point vector layer from an input raster and polygon layer.

The points correspond to the pixel centroids that intersect the polygon layer.

../../../../_images/points_centroids_polygon.png — Obr. 27.42 Points of the pixel centroids

Parameters

Label

Název

Type

Popis

Raster layer

INPUT_RASTER

[raster]

Input raster layer

Vector layer

INPUT_VECTOR

[vector: polygon]

Input polygon vector layer

Points inside polygons

OUTPUT

[vector: point]

Default: [Create temporary layer]

Resulting point layer of pixel centroids. One of:

Create Temporary Layer (TEMPORARY_OUTPUT)
Save to File…
Save to Geopackage…
Save to Database Table…

The file encoding can also be changed here.

Outputs

Label	Název	Type	Popis
Points inside polygons	`OUTPUT`	[vector: point]	Resulting point layer of pixel centroids

Python code

Algorithm ID: native:generatepointspixelcentroidsinsidepolygons

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.7. Import geotagged photos 

Creates a point layer corresponding to the geotagged locations from JPEG images from a source folder.

The point layer will contain a single PointZ feature per input file from which the geotags could be read. Any altitude information from the geotags will be used to set the point’s Z value.

Besides longitude and latitude also altitude, direction and timestamp information, if present in the photo, will be added to the point as attributes.

Parameters

Label	Název	Type	Popis
Input folder	`FOLDER`	[folder]	Path to the source folder containing the geotagged photos
Scan recursively	`RECURSIVE`	[boolean] Default: False	If checked, the folder and its subfolders will be scanned
Photos Optional	`OUTPUT`	[vector: point] Default: `[Create temporary layer]`	Specify the point vector layer for the geotagged photos. One of: Skip Output Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.
Invalid photos table Optional	`INVALID`	[table] Default: `[Skip output]`	Specify the table of unreadable or non-geotagged photos. One of: Skip Output Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.

Outputs

Label

Název

Type

Popis

Photos

OUTPUT

[vector: point]

Point vector layer with geotagged photos. The form of the layer is automatically filled with paths and photo previews settings.

Invalid photos table

Optional

INVALID

[table]

Table of unreadable or non-geotagged photos can also be created.

Python code

Algorithm ID: native:importphotos

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.8. Points to path 

Converts a point layer to a line layer, by joining points in an order defined by an expression or a field in the input point layer.

Points can be grouped by a field or an expression to distinguish line features.

In addition to the line vector layer, a text file is output that describes the resulting line as a start point and a sequence of bearings / directions (relative to azimuth) and distances.

Parameters

Label	Název	Type	Popis
Input point layer	`INPUT`	[vector: point]	Input point vector layer
Create closed paths	`CLOSE_PATH`	[boolean] Default: False	If checked, the first and last points of the line will be connected and close the generated path
Order expression Optional	`ORDER_EXPRESSION`	[expression]	Field or expression providing the order to connect the points in the path. If not set, the feature ID (`$id`) is used.
Sort text containing numbers naturally Optional	`NATURAL_SORT`	[boolean] Default: False	If checked, naturally sorts the features based on the provided expression (i.e., ‚a9‘ < ‚a10‘).
Path group expression Optional	`GROUP_EXPRESSION`	[expression]	Point features of the same value in the field or expression will be grouped in the same line. If not set, a single path is drawn with all the input points.
Paths	`OUTPUT`	[vector: line] Default: `[Create temporary layer]`	Specify the line vector layer of the path. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.
Directory for text output Optional	`OUTPUT_TEXT_DIR`	[folder] Default: `[Skip output]`	Specify the directory that will contain the description files of points and paths. One of: Skip Output Save to a Temporary Directory Save to Directory

Outputs

Label	Název	Type	Popis
Paths	`OUTPUT`	[vector: line]	Line vector layer of the path
Directory for text output	`OUTPUT_TEXT_DIR`	[folder]	Directory containing description files of points and paths

Python code

Algorithm ID: native:pointstopath

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.9. Random points along line 

Creates a new point layer, with points placed on the lines of another layer.

For each line in the input layer, a given number of points is added to the resulting layer. The procedure for adding a point is to:

randomly select a line feature from the input layer
if the feature is multi-part, randomly select a part of it
randomly select a segment of that line
randomly select a position on that segment.

The procedure means that curved parts of the lines (with relatively short segments) will get more points than straight parts (with relatively long segments), as demonstrated in the illustration below, where the output of the Random points along lines algorithm can be compared with the output of the Random points on lines algorithm (that produces points with an, on average, even distribution along the lines).

../../../../_images/randompointsalonglines_illustration.png — Obr. 27.43 Example algorithm output. Left: *Random points along line*, right: *Random points on lines*

A minimum distance can be specified, to avoid points being too close to each other.

Viz také

Random points on lines

Parameters

Label	Název	Type	Popis
Input point layer	`INPUT`	[vector: line]	Input line vector layer
Number of points	`POINTS_NUMBER`	[number] Default: 1	Number of points to create
Minimum distance between points	`MIN_DISTANCE`	[number] Default: 0.0	The minimum distance between points
Random points	`OUTPUT`	[vector: point] Default: `[Create temporary layer]`	The output random points. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.

Outputs

Label	Název	Type	Popis
Random points	`OUTPUT`	[vector: point]	The output random points layer.

Python code

Algorithm ID: qgis:qgisrandompointsalongline

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.10. Random points in extent 

Creates a new point layer with a given number of random points, all of them within a given extent.

A distance factor can be specified, to avoid points being too close to each other. If the minimum distance between points makes it impossible to create new points, either distance can be decreased or the maximum number of attempts may be increased.

Default menu: Vector ► Research Tools

Parameters

Basic parameters

Label	Název	Type	Popis
Input extent	`EXTENT`	[extent]	Map extent for the random points Available methods are: Calculate from layer…: uses extent of a layer loaded in the current project Calculate from layout map…: uses extent of a layout map item in the active project Calculate from bookmark…: uses extent of a saved bookmark Use map canvas extent Draw on canvas: click and drag a rectangle delimiting the area to take into account Enter the coordinates as `xmin, xmax, ymin, ymax`
Number of points	`POINTS_NUMBER`	[number] Default: 1	Number of point to create
Minimum distance between points	`MIN_DISTANCE`	[number] Default: 0.0	The minimum distance between points
Target CRS	`TARGET_CRS`	[crs] Default: Project CRS	CRS of the random points layer
Random points	`OUTPUT`	[vector: point] Default: `[Create temporary layer]`	The output random points. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.

Advanced parameters

Label

Název

Type

Popis

Maximum number of search attempts given the minimum distance

MAX_ATTEMPTS

[number]

Default: 200

Maximum number of attempts to place the points

Outputs

Label	Název	Type	Popis
Random points	`OUTPUT`	[vector: point]	The output random points layer.

Python code

Algorithm ID: native:randompointsinextent

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.11. Random points in layer bounds 

Creates a new point layer with a given number of random points, all of them within the extent of a given layer.

A minimum distance can be specified, to avoid points being too close to each other.

Default menu: Vector ► Research Tools

Parameters

Label	Název	Type	Popis
Input layer	`INPUT`	[vector: polygon]	Input polygon layer defining the area
Number of points	`POINTS_NUMBER`	[number] Default: 1	Number of points to create
Minimum distance between points	`MIN_DISTANCE`	[number] Default: 0.0	The minimum distance between points
Random points	`OUTPUT`	[vector: point] Default: `[Create temporary layer]`	The output random points. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.

Outputs

Label	Název	Type	Popis
Random points	`OUTPUT`	[vector: point]	The output random points layer.

Python code

Algorithm ID: qgis:randompointsinlayerbounds

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.12. Random points in polygons 

Creates a point layer with points placed inside the polygons of another layer.

For each feature (polygon / multi-polygon) geometry in the input layer, the given number of points is added to the result layer.

Per feature and global minimum distances can be specified in order to avoid points being too close in the output point layer. If a minimum distance is specified, it may not be possible to generate the specified number of points for each feature. The total number of generated points and missed points are available as output from the algorithm.

The illustration below shows the effect of per feature and global minimum distances and zero/non-zero minimum distances (generated with the same seed, so at least the first point generated will be the same).

../../../../_images/randompointsinpolygons_mindistance.png — Obr. 27.44 Ten points per polygon feature, *left*: min. distances = 0, *middle*: min.distances = 1, *right*: min. distance = 1, global min. distance = 0

The maximum number of tries per point can be specified. This is only relevant for non-zero minimum distance.

A seed for the random number generator can be provided, making it possible to get identical random number sequences for different runs of the algorithm.

The attributes of the polygon feature on which a point was generated can be included (Include polygon attributes).

If you want approximately the same point density for all the features, you can data-define the number of points using the area of the polygon feature geometry.

Viz také

Random points inside polygons

Parameters

Basic parameters

Label	Název	Type	Popis
Input polygon layer	`INPUT`	[vector: line]	Input polygon vector layer
Number of points for each feature	`POINTS_NUMBER`	[number ] Default: 1	Number of points to create
Minimum distance between points Optional	`MIN_DISTANCE`	[number ] Default: 0.0	The minimum distance between points within one polygon feature
Random points in polygons	`OUTPUT`	[vector: point] Default: `[Create temporary layer]`	The output random points. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.

Advanced parameters

Label	Název	Type	Popis
Global minimum distance between points Optional	`MIN_DISTANCE_GLOBAL`	[number ] Default: 0.0	The global minimum distance between points. Should be smaller than the Minimum distance between points (per feature) for that parameter to have an effect.
Maximum number of search attempts (for Min. dist. > 0) Optional	`MAX_TRIES_PER_POINT`	[number ] Default: 10	The maximum number of tries per point. Only relevant if the minimum distance between points is set (and greater than 0).
Random seed Optional	`SEED`	[number] Default: Not set	The seed to use for the random number generator.
Include polygon attributes	`INCLUDE_POLYGON_ATTRIBUTES`	[boolean] Default: True	If set, a point will get the attributes from the line on which it is placed.

Outputs

Label	Název	Type	Popis
Random points in polygons	`OUTPUT`	[vector: point]	The output random points layer.
Number of features with empty or no geometry	`FEATURES_WITH_EMPTY_OR_NO_GEOMETRY`	[number]
Total number of points generated	`OUTPUT_POINTS`	[number]
Number of missed points	`POINTS_MISSED`	[number]	The number of points that could not be generated due to the minimum distance constraint.
Number of features with missed points	`POLYGONS_WITH_MISSED_POINTS`	[number]	Not including features with empty or no geometry

Python code

Algorithm ID: native:randompointsinpolygons

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.13. Random points inside polygons 

Creates a new point layer with a given number of random points inside each polygon of the input polygon layer.

Two sampling strategies are available:

Points count: number of points for each feature
Points density: density of points for each feature

A minimum distance can be specified, to avoid points being too close to each other.

Default menu: Vector ► Research Tools

Viz také

Random points in polygons

Parameters

Label	Název	Type	Popis
Input layer	`INPUT`	[vector: polygon]	Input polygon vector layer
Sampling strategy	`STRATEGY`	[enumeration] Default: 0	Sampling strategy to use. One of: 0 — Points count: number of points for each feature 1 — Points density: density of points for each feature
Point count or density	`VALUE`	[number ] Default: 1.0	The number or density of points, depending on the chosen Sampling strategy.
Minimum distance between points	`MIN_DISTANCE`	[number] Default: 0.0	The minimum distance between points
Random points	`OUTPUT`	[vector: point] Default: `[Create temporary layer]`	The output random points. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.

Outputs

Label	Název	Type	Popis
Random points	`OUTPUT`	[vector: point]	The output random points layer.

Python code

Algorithm ID: qgis:randompointsinsidepolygons

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.14. Random points on lines 

Creates a point layer with points placed on the lines of another layer.

For each feature (line / multi-line) geometry in the input layer, the given number of points is added to the result layer.

Per feature and global minimum distances can be specified in order to avoid points being too close in the output point layer. If a minimum distance is specified, it may not be possible to generate the specified number of points for each feature. The total number of generated points and missed points are available as output from the algorithm.

The illustration below shows the effect of per feature and global minimum distances and zero/non-zero minimum distances (generated with the same seed, so at least the first point generated will be the same).

../../../../_images/randompointsonlines_mindistance.png — Obr. 27.45 Five points per line feature, *left*: min. distances = 0, *middle*: min.distances != 0, *right*: min. distance != 0, global min. distance = 0

The maximum number of tries per point can be specified. This is only relevant for non-zero minimum distance.

A seed for the random number generator can be provided, making it possible to get identical random number sequences for different runs of the algorithm.

The attributes of the line feature on which a point was generated can be included (Include line attributes).

If you want approximately the same point density for all the line features, you can data-define the number of points using the length of the line feature geometry.

Viz také

Random points along line

Parameters

Basic parameters

Label	Název	Type	Popis
Input line layer	`INPUT`	[vector: line]	Input line vector layer
Number of points for each feature	`POINTS_NUMBER`	[number ] Default: 1	Number of points to create
Minimum distance between points (per feature) Optional	`MIN_DISTANCE`	[number ] Default: 0.0	The minimum distance between points within one line feature
Random points on lines	`OUTPUT`	[vector: point] Default: `[Create temporary layer]`	The output random points. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.

Advanced parameters

Label	Název	Type	Popis
Global minimum distance between points Optional	`MIN_DISTANCE_GLOBAL`	[number ] Default: 0.0	The global minimum distance between points. Should be smaller than the Minimum distance between points (per feature) for that parameter to have an effect.
Maximum number of search attempts (for Min. dist. > 0) Optional	`MAX_TRIES_PER_POINT`	[number ] Default: 10	The maximum number of tries per point. Only relevant if the minimum distance between points is set (and greater than 0).
Random seed Optional	`SEED`	[number] Default: Not set	The seed to use for the random number generator.
Include line attributes	`INCLUDE_LINE_ATTRIBUTES`	[boolean] Default: True	If set, a point will get the attributes from the line on which it is placed.

Outputs

Label	Název	Type	Popis
Random points on lines	`OUTPUT`	[vector: point]	The output random points layer.
Number of features with empty or no geometry	`FEATURES_WITH_EMPTY_OR_NO_GEOMETRY`	[number]
Number of features with missed points	`LINES_WITH_MISSED_POINTS`	[number]	Not including features with empty or no geometry
Total number of points generated	`POINTS_GENERATED`	[number]
Number of missed points	`POINTS_MISSED`	[number]	The number of points that could not be generated due to the minimum distance constraint.

Python code

Algorithm ID: native:randompointsonlines

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.15. Raster pixels to points 

Creates a vector layer of points corresponding to each pixel in a raster layer.

Converts a raster layer to a vector layer, by creating point features for each individual pixel’s center in the raster layer. Any nodata pixels are skipped in the output.

Parameters

Label	Název	Type	Popis
Raster layer	`INPUT_RASTER`	[raster]	Input raster layer
Band number	`RASTER_BAND`	[raster band]	Raster band to extract data from
Field name	`FIELD_NAME`	[string] Default: ‚VALUE‘	Name of the field to store the raster band value
Vector points	`OUTPUT`	[vector: point] Default: `[Create temporary layer]`	Specify the resulting point layer of pixels centroids. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.

Outputs

Label	Název	Type	Popis
Vector points	`OUTPUT`	[vector: point]	Resulting point layer with pixels centroids

Python code

Algorithm ID: native:pixelstopoints

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.16. Raster pixels to polygons 

Creates a vector layer of polygons corresponding to each pixel in a raster layer.

Converts a raster layer to a vector layer, by creating polygon features for each individual pixel’s extent in the raster layer. Any nodata pixels are skipped in the output.

Parameters

Label	Název	Type	Popis
Raster layer	`INPUT_RASTER`	[raster]	Input raster layer
Band number	`RASTER_BAND`	[raster band]	Raster band to extract data from
Field name	`FIELD_NAME`	[string] Default: ‚VALUE‘	Name of the field to store the raster band value
Vector polygons	`OUTPUT`	[vector: polygon] Default: `[Create temporary layer]`	Specify the resulting polygon layer of pixel extents. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.

Outputs

Label	Název	Type	Popis
Vector polygons	`OUTPUT`	[vector: polygon]	Resulting polygon layer of pixel extents

Python code

Algorithm ID: native:pixelstopolygons

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.

27.1.16.17. Regular points 

Creates a new point layer with its points placed in a regular grid within a given extent.

The grid is specified either by the spacing between the points (same spacing for all dimensions) or by the number of points to generate. In the latter case, the spacing will be determined from the extent. In order to generate a full rectangular grid, at least the number of points specified by the user is generated for the latter case.

Random offsets to the point spacing can be applied, resulting in a non-regular point pattern.

Default menu: Vector ► Research Tools

Parameters

Label	Název	Type	Popis
Input extent (xmin, xmax, ymin, ymax)	`EXTENT`	[extent]	Map extent for the random points Available methods are: Calculate from layer…: uses extent of a layer loaded in the current project Calculate from layout map…: uses extent of a layout map item in the active project Calculate from bookmark…: uses extent of a saved bookmark Use map canvas extent Draw on canvas: click and drag a rectangle delimiting the area to take into account Enter the coordinates as `xmin, xmax, ymin, ymax`
Point spacing/count	`SPACING`	[number] Default: 100	Spacing between the points, or the number of points, depending on whether `Use point spacing` is checked or not.
Initial inset from corner (LH side)	`INSET`	[number] Default: 0.0	Offsets the points relative to the upper left corner. The value is used for both the X and Y axis.
Apply random offset to point spacing	`RANDOMIZE`	[boolean] Default: False	If checked the points will have a random spacing
Use point spacing	`IS_SPACING`	[boolean] Default: True	If unchecked the point spacing is not taken into account
Output layer CRS	`CRS`	[crs] Default: Project CRS	CRS of the random points layer
Regular points	`OUTPUT`	[vector: point] Default: `[Create temporary layer]`	Specify the output regular point layer. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.

Outputs

Label	Název	Type	Popis
Regular points	`OUTPUT`	[vector: point]	The output regular point layer.

Python code

Algorithm ID: qgis:regularpoints

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.