Mesh2Raster

Introduction

This utility generates an ASCII-raster file based on a 2D surface mesh. A raster is superimposed on the mesh and pixel values are set to the surface elevation at each pixel’s position. If no mesh element is located beneath a pixel it’s value is set to NODATA.

Usage

   Mesh2Raster  -i <string> -o <string> [-c <real>]


Where:

   -i <string>,  --input-file <string>
     (required)  Mesh input file (*.vtu, *.msh)

   -o <string>,  --output-file <string>
     (required)  Raster output file (*.asc)

   -c <real>,  --cellsize <real>
     edge length of raster cells in result

The parameter c specifies the cell size (i.e. pixel size) of the raster. While optional, it is still recommended to choose a value as the default will be set to the minimum edge length in the input mesh which for unstructured grids may result in a very fine and (extremely) large output raster.

Simple example

Input data:

The input mesh for this example is a homogeneous, unstructured triangle mesh with an average edge length of 100m.

Command:

Mesh2Raster -i input.vtu -o output.asc -c 50

Command:

Mesh2Raster -i input.vtu -o output.asc -c 200

Command:

Mesh2Raster -i input.vtu -o output.asc -c 1000

Application

The resulting ASCII-rasters can be used to represent surface data in geographic information systems. In the absence of input data, a detailed raster can also be used by OpenGeoSys preprocessing tools to generate new surface meshes with different resolution or properties.