Simplify or Smooth a Surface

Use the Simplify or Smooth a Surface option (geogxnet.dll(Geosoft.GX.Surface.SimplifyOrSmoothSurface;Run)*), to decrease or increase the level of detail in the surface. The resulting surface may be saved to either a new or an existing geosurface file. If a 3D View is open in your workspace, the target geosurface file will be displayed.

You can access the option from:

  • The Oasis montaj Geosurface > Utilities > Simplify or Smooth a Surface menu

  • The Oasis montaj 3D View >  Geosurface > Utilities > Simplify or Smooth a Surface menu

  • The 3D Viewer Geosurface > Utilities > Simplify or Smooth a Surface menu

Simplify or Smooth a Surface dialog options

Input geosurface

Select the existing geosurface file that contains the surface you wish to modify.

Script Parameters: SIMPLIFY_SMOOTH_GEOSURFACE.INPUT_GEOSURFACE_FILE

Input surface

Select the existing surface you wish to modify from the list of surfaces in the input geosurface file.

Script Parameters: SIMPLIFY_SMOOTH_GEOSURFACE.INPUT_SURFACE_NAME

Output geosurface

Specify the name of a new or existing geosurface file in which the modified surface will be written.

Script Parameters: SIMPLIFY_SMOOTH_GEOSURFACE.OUTPUT_GEOSURFACE_FILE

Output surface

Specify a name for the new surface. If a surface by that name already exists in the output geosurface file, it will be overwritten.

Script Parameters: SIMPLIFY_SMOOTH_GEOSURFACE.OUTPUT_SURFACE_NAME

Colour

Select a colour for the new surface. The default colour is Magenta.

Script Parameters: SIMPLIFY_SMOOTH_GEOSURFACE.SURFACE_COLOR

Operations

Simplification

Select this option to simplify your surface, describing it with approximately half as many triangles and therefore producing a more coarse surface. See Application Notes below.

Script Parameters: SIMPLIFY_SMOOTH_GEOSURFACE.SIMPLIFY_RADIO_BUTTON

Smooth/beautify

Select this option to smooth or beautify your surface, which effectively places an additional vertex in the middle of each side and fits a smooth surface to the vertices. The output surface contains approximately four times as many triangles and vertices and fewer sharp edges. See Application Notes below.

Script Parameters: SIMPLIFY_SMOOTH_GEOSURFACE.SMOOTH_BEAUTIFY_RADIO_BUTTON

Application Notes

*The GX tool will search in the "...\Geosoft\Desktop Applications \gx" folder. The GX.Net tools, however, are embedded in the geogxnet.dll located in the "...\Geosoft\Desktop Applications \bin" folder. If running this GX interactively, bypassing the menu, first change the folder to point to the "bin" folder, then supply the GX.Net tool in the specified format.

  • The Simplification function simplifies the surface by doing an ‘edge-collapse’ operation repeatedly; essentially it replaces an edge with a vertex, and in doing so reduces the number of faces in the surface. This function reduces the number of edges (triangle sides) in the surface by half.
  • The Smooth/beautify function uses an algorithm called "Loop subdivision" to subdivide each triangle into four smaller triangles. The method is based on a quartic box spline.
  • A new output geosurface will have the same projected coordinate system and units as the input geosurface.
  • If the output geosurface exists, the resulting surface(s) will be reprojected into the projected coordinate system and units of the output geosurface.

See Also: