# filters.faceraster

The FaceRaster filter creates a raster from a point cloud using an algorithm based on an existing triangulation. Each raster cell is given a value that is an interpolation of the known values of containing triangle. If the raster cell center is outside of the triangulation, it is assigned the nodata value. Use writers.raster to write the output.

The extent of the raster can be defined by using the origin_x, origin_y, width and height options. If these options aren’t provided the raster is sized to contain the input data.

Default Embedded Stage

This stage is enabled by default

## Basic Example

This pipeline reads the file autzen_trim.las and creates a raster based on a Delaunay trianguation of the points. It then creates a raster, interpolating values based on the vertices of the triangle that contains each raster cell center.

    [
        "pdal/test/data/las/autzen_trim.las",
        {
            "type": "filters.delaunay"
        },
        {
            "type": "filters.faceraster",
            "resolution": 2,
            "width": 500,
            "height": 500,
            "origin_x": 636000,
            "origin_y": 849000
        }
    ]

## Options

resolution

  Length of raster cell edges in X/Y units. [Required]

nodata

  The value to use for a raster cell if no data exists in the input data with which to compute an output cell value. Note that this value may be different from the value used for nodata when the raster is written. [Default: NaN]

mesh

  Name of the triangulation to use for interpolation. If not provided, the first triangulation associated with the input points will be used. [Default: None]

origin_x

  X origin (lower left corner) of the grid. [Default: None]

origin_y

  Y origin (lower left corner) of the grid. [Default: None]

width

  Number of cells in the X direction. [Default: None]

height

  Number of cells in the Y direction. [Default: None]

where

  An expression that limits points passed to a filter. Points that don’t pass the expression skip the stage but are available to subsequent stages in a pipeline. [Default: no filtering]

where_merge

  A strategy for merging points skipped by a ‘where’ option when running in standard mode. If `true`, the skipped points are added to the first point view returned by the skipped filter. If `false`, skipped points are placed in their own point view. If `auto`, skipped points are merged into the returned point view provided that only one point view is returned and it has the same point count as it did when the filter was run. [Default: `auto`]