Import geometry from a DTM or a geometer reading

We offer an online tool to extract cross profiles and create a SIC text import file from a DTM or a geometer reading:

http://sic.g-eau.fr/sic_tools/import_xyz.html

Two methods of extracting cross profiles are proposed: one is more suitable for homogeneous point measurements such as DTMs, the other is more suitable for surveyor measurements where cross profiles have been recorded.

Format of the import file for points with coordinates (X, Y, Z)

The import file is a text file containing 3 columns representing the abscissa, ordinate and altitude in an orthonormal and metric reference frame of the geometry points recorded in the field (For example, points referenced in the Lambert coordinate system for France). The accepted separators for the columns are tabulation, semicolon and comma. The character used for decimals is the point.

Example of a file in Lambert coordinates with tab separator:

It is recommended to put the tool directly in full screen before importing the file. The import consists in choosing the file on the hard disk using the "Browse..." button and clicking on the "Process file" button.

Trace of the central flow route

Once the file has been imported, you must indicate where the stream to be digitized is located by drawing the central flow route with the mouse. This is done by placing, with a mouse click, nodes that will form a set of segments.

The kilometric point (pK) is indicated at each plotted node. It is possible to restart your route by clicking on the "Reset route" button.

Extraction of cross profiles from a DTM

This tool allows cross profiles to be extracted at regular intervals by transforming the point reading into a digital terrain model using the Delaunay triangulation method.

Access to this tool is via the "Export for SIC²" button. The tool parameters are as follows:

  • Space step (m): the desired space step between each cross section (in meters);
  • Section width (m): the maximum width of the section (in meters). Beyond this distance from the center line, the intersections of the section with the edges of the Delaunay triangles will be ignored;
  • Max length of triangle edges (m): Maximum length of the edges of the Delaunay triangles.

Pressing the "Generate section profiles" button starts the tool with the selected parameters. The result is displayed graphically and produces a text to copy and paste intothe EdiSIC text format cross section and profile import tool. The operation may take time and you must wait even if the browser indicates that a script is blocking the operation of the application.

Extraction of cross profiles from a survey of cross profiles

This tool automatically creates sections for SIC² at the location where cross-sectional profile surveys were performed. The algorithm converts the coordinates of the points into a reference point corresponding to the line of the central flow line (pK axis). It then groups the related points by section.

Access to the tool is via the "Export pK coords for SIC²" button. The tool parameters are as follows:

  • Max Length between points (m): maximum distance along the pK axis between two points for a grouping in the same section (in meters);
  • Max width of cross profiles (m): maximum width of cross sections (in meters). Beyond this width, the points are ignored.
  • Min number of points in section: minimum number of points to constitute a cross section. If a grouping of points does not reach this minimum limit, the section is ignored.

Pressing the "Generate section profiles" button starts the tool with the selected parameters. The result is displayed graphically and produces a text to copy and paste intothe EdiSIC text format cross section and profile import tool. The operation may take time and you must wait even if the browser indicates that a script is blocking the operation of the application.