Description
The SimplifyFeatures process removes vertices to create simpler features by applying the Douglas-Peucker algorithm.
Inputs
Features in a supported format. HPD Database URI, HOB, and 000 (S-57 specification) are supported.
Outputs
Features in HOB format.
Command Line Syntax
carisbatch --run SimplifyFeatures --feature-catalogue <value> --tolerance <value> [options] <input> <output>
User Interface Command
Simplify/Smooth
Options
The following table describes the parameters available for this process.
Parameter |
| |||
|---|---|---|---|---|
Long | Short | Description | Can Repeat | Notes
|
--feature-catalogue | F | A string specifying the name of the catalogue that defines the features and attributes in a vector dataset. One of {list dynamically populated from the catalogue control file}. The names of the available catalogues can be accessed through application via the Object Catalogue environment variable in Tools > Options. The available catalogues are controlled by the Catalogue Control file. An example of a catalogue name is "S-57 ENC 3.1". | FALSE | This must be specified for HOB input. |
--tolerance | T | A number and unit specifying the distance that individual vertices can be moved when simplifying features. Trend lines are used between different vertices along each feature. If any vertices in the input are farther than the tolerance from the trend line, more trend lines are applied over smaller portions of the feature. This process is repeated until no input vertices are farther than the tolerance from the set of trend lines. The trend lines are then used as the output feature. A tolerance of 0m results in only collinear vertices being removed. Any larger tolerance value may change the geometry of the input features. | FALSE | This must be specified explicitly. |
--scale | s | A number specifying the scaling to apply to the tolerance (1:scale). The default scale value is 1, such that the tolerance represents a distance on the ground; the tolerance would then be a value like 0.5m. A scale of 1000 would mean that the tolerance represents a distance on a map at 1:1000 scale; the tolerance would then be a value like 1mm. | FALSE | |
Example
To use this command refer to the following example.
Example | ||
|---|---|---|
Objective | You want to reduce the number of vertices in a line feature. | |
Description | Command Line Syntax | |
The S-57 ENC 3.1 catalogue is to be used. | --feature-catalogue "S-57 ENC 3.1" | |
Vertices can be no more than 5m from a trend line. | --tolerance 5m | |
The data source is named LineFeatures.hob and is located in the BatchSample directory, on the D drive. | D:\BatchSample\LineFeatures.hob | |
The simplified line will be saved to SimpliedFeatures.hob in the source data location. | D:\BatchSample\SimplifiedFeatures.hob | |
Command Line |
| |
Outcome | A new HOB file is created containing the simplified line feature. | |
Extra Notes | N/A | |