The module allows one to retrieve a point cloud from a virtual point cloud dataset by applying the provided area-of-interest (AOI). The extent of the AOI can be provided either as polygon shapefile, grid or by coordinates. Optionally, an overlap can be added to the AOI and a spcvf tile info file can be outputted. The latter can be used to remove the overlap later.
In case an overlap is used and the AOI is provided as polygon shapfile, only the bounding boxes of the polygons are used.
With polygon shapefiles additional functionality is available:
* in case one or more polygons are selected, only the selected polygons are used.
* in case the shapefile contains several polygons and the 'One Point Cloud per Polygon' parameter is checked, a point cloud dataset is outputted for each polygon. In case the 'Tilename' attribute is provided, the output files are named by this attribute. Otherwise the output file names are build from the lower left coordinate of each tile.
The derived datasets can be outputted either as point cloud list or written to an output directory. For the latter, you must provide a valid file path with the 'Optional Output Filepath' parameter.
Optionally, the query can be constrained by providing an attribute field and a value range that must be met.
A virtual point cloud dataset is a simple XML format with the file extension .spcvf, which can be created with the 'Create Virtual Point Cloud Dataset' module.
| | Name | Type | Identifier | Description | Constraints |
|---|
| Input | Shape (*) | Shapes (optional input) | AOI_SHP | Shapefile describing the AOI. | - |
| Grid (*) | Grid (optional input) | AOI_GRID | Grid describing the AOI. | - |
| Output | Point Cloud (*) | Point Cloud list (optional output) | PC_OUT | The output point cloud(s) | - |
| Options | Filename | File path | FILENAME | The full path and name of the .spcvf file | - |
| Optional Output Filepath | File path | FILEPATH | The full path to which the output(s) should be written. Leave empty to output the datasets as point cloud list. | - |
| Copy existing Attributes | Boolean | COPY_ATTR | Copy attributes from input to output point cloud. | Default: 1 |
| Copy Attributes | Text | ATTRIBUTE_LIST | Field numbers (starting from 1) of the attributes to copy, separated by semicolon; fields one to three (x;y;z) are mandatory. | Default: 1;2;3 |
| Constrain Query | Boolean | CONSTRAIN_QUERY | Check this parameter to constrain the query by an attribute range. | Default: 0 |
| Attribute Field | Integer | ATTR_FIELD | The attribute field to use as constraint. Field numbers start with 1. | Minimum: 1
Default: 1 |
| Value Range | Value range | VALUE_RANGE | Minimum and maximum of attribute range []. | - |
| Tilename (*) | Table field | FIELD_TILENAME | Attribute used for naming the output file(s) | - |
| Grid system | Grid system | AOI_GRID_GRIDSYSTEM | - | - |
| X-Extent | Value range | AOI_XRANGE | Minimum and maximum x-coordinate of AOI. | - |
| Y-Extent | Value range | AOI_YRANGE | Minimum and maximum y-coordinate of AOI. | - |
| Add Overlap | Boolean | AOI_ADD_OVERLAP | Add overlap to AOI | Default: 0 |
| Overlap | Floating point | OVERLAP | Overlap [map units] | Minimum: 0.000000
Default: 50.000000 |
| Optional Tile Info Filename | File path | FILENAME_TILE_INFO | The full path and name of an optional spcvf tile info file. Such a file contains information about the bounding boxes without overlap and can be used to remove the overlap from the tiles later. Leave empty to not output such a file. | - |
| One Point Cloud per Polygon | Boolean | ONE_PC_PER_POLYGON | Write one point cloud dataset for each polygon | Default: 0 |
| (*) optional |