Manipulate massive terrain and point data sets with SCALGO Utility

The Burn module can e.g. be used to add features to, or remove features from, a terrain model as illustrated in the above right figure (where building has been added and bridges removed using the Burn module). It can also e.g. be used to modify features that are already in the model, such as to make sure water bodies are completely flat.

The module allows detailed user control. On rasters, it is for example possible to control if a cell should be modified if the center, any part, or the entire cell is contained in a polygon. Using point data given in a LAS format where each point is assigned a class, it is possible to work on specific classes. When input polygons are overlapping it is possible to control exactly what burn value to use in overlapping regions (the highest, lowest, the average or the sum of the overlapping burn values). It is e.g. also possible control how nodata values are handled.

The module allows detailed user control. On rasters, it is for examle possible to control if a cell should be modified if the center, any part, or the entire cell is contained in a polygon. It is also possible to control if the output raster should be the same size as the input raster (with nodata in clipped cells) or the size of the bounding box of the input polygons. On point data given in a LAS format where each point is assigned a class, it is possible to work on specific classes.

This module allows the user to easily convert a large raster into smaller regions corresponding to e.g. local administrative regions.

Left: An input raster and polygons with their field values set to letters of the alphabet. Right: the result of partitioning the input raster and writing the output to .tif-files.

The module is useful for vectorizing e.g. rasters of watershed labels as computed by the Watersheds module in the Hydrology package, resulting in one polygon per watershed.

Left: A watershed raster. Right: The 4 polygons output by the Vectorize module.

Functions evaluated using the Calculate module can be quite involved containing arithmetic, Boolean and conditional expressions; The function used in the above example to the right would be (a<5?nodata:a), where a refers to the single raster input. Multiband rasters are also supported by the module, such that the individual bands can be part of the evaluated function, just as the output raster can be a multiband raster.

The Aggregate module supports a number of functions, including mean, min, max and sum. If C or R is not divisible by w some of the (boundary) cells in the input raster will be ignored. Optionally, the module can add nodata cells to the input raster such that C and R are divisible by w and no input cells are ignored.

The thresholds used by the module can be given using a simple syntax where one or more ranges and a threshold granularity is given. The Masks module is for example useful when discretizing the very general output from the SCALGO Hydrology Sea-Levels module into a set of masks that indicate flooded cells for a set of equidistant thresholds (for example for every 10cm from 0 to 10 meters).

The Convert module primarily converts between data sets of the same type, that is, it converts between a number of raster types (e.g. between tif, bil and img), between two point set types (las and csv), as well as between two TIN types (a simple text and a binary format). It can also convert a raster type to a point set type, where each raster cell is converted to a point at the center of the cell with the value of the cell as its height.