Visualization Guide
Visualization Guide
Visualization Guide

Facet Smoothing

Use it!

Used to improve the rendered quality of discrete polygons. To do this their normals are calculated by averaging the normals of adjacent polygons, thereby softening their otherwise harsh appearance. Applications where this is desirable include digital terrain modeling and where approximated surfaces have been created, usually as a result of translating a file.

The new normals are written to the selected polygons as attribute linkage data. The polygons themselves are not modified.

Tool SettingEffect
Mode

Sets the operation to be performed:

  • Attach
    • — To select the polygons that are to be included in the smoothing process.
  • Detach
    • — Remove selected polygons from the smoothing process.
Angle Tolerance

Sets the maximum angle between faces that are smoothed. If the angle between two adjacent shapes is larger than the Angle Tolerance value, the edge is not smoothed. (This setting is useful because a typical model contains a set of faces with both sharp edges [that should not be smoothed] and edges that should be smoothed.)

To smooth a set of polygons
  1. Select the polygons to be smoothed.

  2. Select the Facet Smoothing tool.

  3. In the Tool Settings window, set Mode to Attach.

  4. Accept.

Alternative Method — To smooth a set of polygons
  1. Select the Facet Smoothing tool.

  2. In the Tool Settings window, set Mode to Attach.

  3. Identify the element to be smoothed.

  4. Accept or identify additional elements.

  5. Repeat for each desired element.

  6. Reset to smooth all selected elements.

    7. There is no tolerance to which polygons can be gapped. If the similar sides of a polygon do not occupy the same points, the tool will not work.

To unsmooth a set of polygons
  1. Select the polygons to be unsmoothed.

  2. Select the Facet Smoothing tool.

  3. In the Tool Settings window, set Mode to Detach.

  4. Accept.

Alternative Method — To unsmooth a set of polygons
  1. Select the Facet Smoothing tool.

  2. In the Tool Settings window, set Mode to Detach.

  3. Identify the element to be unsmoothed.

  4. Accept or identify additional elements. Repeat for each desired element.

Key-in: RENDER SHAPE ICON


or

Key-in: RENDER SHAPE CLEAR SMOOTH

Using the Facet Smoothing tool does not change the appearance of wireframe polygons. Only during the rendering process is the smoothing effect evident.

Rendered image of a digital terrain model, in which the polygon mesh is clearly visible.

  

Same digital terrain model after applying facet smoothing. The polygon mesh has been smoothed during the rendering process.