Simplify Line

Function Description: Simplifies lines by removing relatively extraneous vertices while preserving essential shape.

Data Description

Input and Output Relationship

Input and Output Relationship for Simplify Line

Description:

• The Simplification Tolerance parameter value is used to determine the degree of simplification. A larger tolerance results in a coarser geometry, while a smaller tolerance produces a geometry that is closer to the input geometry.
  • For the Distance (Douglas-Peucker) algorithm, the tolerance represents the maximum allowed vertical distance between each vertex and the newly created line.
  • For the Area (Visvalingam) algorithm, the tolerance is defined as the area of a valid triangle formed by three adjacent vertices, normalized to the length of the corresponding square side.
  • For the Snap to Grid algorithm, the tolerance is the length of the grid cell.

Steps

1. Navigate to Toolbox -> Vector Tools -> Cartography -> Simplify Line tool, and double-click to open the function window.

Simplify Line

Parameter Description:

• Input Features: The input line features to be simplified.

• Simplification Algorithm: Specifies the algorithm used for line simplification.

  • Distance (Douglas-Peucker) - Retains key points that define the basic shape of the line while removing all other points (Douglas-Peucker). This is the default setting.
  • Area (Visvalingam) - Retains vertices that form valid triangles based on their area.
  • Snap to Grid - Retains vertices that lie outside the grid tolerance.

• Simplification Tolerance: This tolerance determines the degree of simplification. You can select a preferred unit; otherwise, the unit of the input data will be used.

  • For the Distance (Douglas-Peucker) algorithm, the tolerance represents the maximum allowed vertical distance between each vertex and the newly created line.
  • For the Area (Visvalingam) algorithm, the tolerance is the area of a valid triangle defined by three adjacent vertices, normalized to the length of the corresponding square side.
  • For the Snap to Grid algorithm, the tolerance is the length of the grid cell.

• Output Feature Class: The output line feature class containing the simplified results, which includes all fields from the input feature class.

• Add Result to Project: This option is only applicable when the output feature class is saved to the project's gpkg database. When checked, it will automatically create a layer for the result and add it to the project.