Transect (fixed interval) alg (#10798)

Author: DelazJ

docs/user_manual/processing_algs/qgis/img/transect.png

@@ -7542,16 +7542,7 @@ Creates transects on vertices for (multi)linestring.
 A transect is a line oriented from an angle (by default perpendicular)
 to the input polylines (at vertices).
 
-Field(s) from feature(s) are returned in the transect with these
-new fields:
-
-* 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: Total length of the transect returned
-* TR_ORIENT: Side of the transect (only on the left or right of
-  the line, or both side)
+The output transect layer includes the original feature fields along with new transect fields.
 
 .. warning::
  This algorithm drops existing primary keys or FID values and regenerates them in output layers.
@@ -7561,6 +7552,8 @@ new fields:
 
    Dashed red lines represent the transect of the input line layer
 
+.. seealso:: :ref:`qgistransectfixeddistance`
+
 Parameters
 ..........
 
@@ -7597,7 +7590,17 @@ Parameters
        * 0 --- Left
        * 1 --- Right
        * 2 --- Both
+   * - **Direction**
 
+       Optional
+     - ``DIRECTION``
+     - [enumeration]
+  
+       Default: ``0``
+     - Orientation direction for transects:
+       
+       * 0 --- Left to Right
+       * 1 --- Right to Left
    * - **Transect**
      - ``OUTPUT``
      - [vector: line]
@@ -7625,7 +7628,15 @@ Outputs
    * - **Transect**
      - ``OUTPUT``
      - [vector: line]
-     - Output line layer
+     - Output line layer.
+       The output layer contains the following fields:
+  
+       - ``TR_FID``: ID of the original feature
+       - ``TR_ID``: ID of the transect. Each transect have a 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``: Total length of the transect returned
+       - ``TR_ORIENT``: Side of the transect (only on the left or right of the line, or both side)
 
 Python code
 ...........
@@ -7636,6 +7647,129 @@ Python code
   :start-after: **algorithm_code_section**
   :end-before: **end_algorithm_code_section**
 
+.. _qgistransectfixeddistance:
+
+Transect (fixed distance)
+-------------------------
+
+Creates transects at fixed distance intervals along (multi)linestrings.
+
+A transect is a line oriented from an angle (by default perpendicular)
+to the input polylines at regular intervals.
+
+The output transect layer includes the original feature fields along with new transect fields.
+
+.. warning::
+ This algorithm drops existing primary keys or FID values and regenerates them in output layers.
+
+.. figure:: img/transect_fixed_distance.png
+   :align: center
+
+   Transects (red lines) created at fixed intervals along the input line layer (blue lines)
+
+.. seealso:: :ref:`qgistransect`
+
+Parameters
+..........
+
+.. list-table::
+   :header-rows: 1
+   :widths: 20 20 20 40
+   :class: longtable
+
+   * - Label
+     - Name
+     - Type
+     - Description
+   * - **Input layer**
+     - ``INPUT``
+     - [vector: line]
+     - Input line vector layer
+   * - **Fixed sampling interval**
+     - ``INTERVAL``
+     - [numeric: double]
+  
+       Default: ``10.0``
+     - Distance between transects along the line
+   * - **Length of the transect**
+     - ``LENGTH``
+     - [numeric: double] |dataDefine|
+  
+       Default: ``5.0``
+     - Total length of each transect line
+   * - **Angle from original line at the vertices**
+     - ``ANGLE``
+     - [numeric: double] |dataDefine|
+  
+       Default: ``90.0``
+     - Angle in degrees from the original line. A value of 90° creates
+       perpendicular transects
+   * - **Side to create the transects**
+     - ``SIDE``
+     - [enumeration]
+  
+       Default: ``0``
+     - Which side of the line to create transects on (relative to the line
+       digitizing direction):
+       
+       * 0 --- Left
+       * 1 --- Right
+       * 2 --- Both
+   * - **Direction**
+       Optional
+     - ``DIRECTION``
+     - [enumeration]
+  
+       Default: ``0``
+     - Orientation direction for transects:
+       
+       * 0 --- Left to Right
+       * 1 --- Right to Left
+   * - **Transect**
+     - ``OUTPUT``
+     - [vector: line]
+  
+       Default: ``[Create temporary layer]``
+     - Specification of the output line layer.
+       :ref:`One of <output_parameter_widget>`:
+
+       .. include:: ../algs_include.rst
+          :start-after: **file_output_types**
+          :end-before: **end_file_output_types**
+
+Outputs
+.......
+
+.. list-table::
+   :header-rows: 1
+   :widths: 20 20 20 40
+   :class: longtable
+
+   * - Label
+     - Name
+     - Type
+     - Description
+   * - **Transect**
+     - ``OUTPUT``
+     - [vector: line]
+     - Output line layer containing the generated transects.
+       The output layer contains the following fields:
+  
+       - ``TR_FID``: ID of the original feature
+       - ``TR_ID``: ID of the transect. Each transect have a 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``: Total length of the transect returned
+       - ``TR_ORIENT``: Side of the transect (only on the left or right of the line, or both side)
+
+Python code
+...........
+
+**Algorithm ID**: ``native:transectfixeddistance``
+
+.. include:: ../algs_include.rst
+  :start-after: **algorithm_code_section**
+  :end-before: **end_algorithm_code_section**
 
 .. _qgistranslategeometry: