ET TerrainViewer uses four types of layers

• Surface layers - the sources of the surface layers can be
  • PolygonZ TIN created with the Build TIN function of ET Surface or ET GeoWizards
  • Raster datasets - see supported formats here
• Feature layers - shapefiles with or without Z values.
• Image layers - three-band raster datasets (e.g. aerial photos). See supported formats here.
• Graphic layers - a custom layer of point markers, created manually. One graphic layer per project is supported.

The software checks the dataset that is loaded and determines the type of the layer automatically. The first layer loaded in a new project must be a surface layer.

General Layer Properties

Z Values

You can define how the Z values of the layer will be derived.

• Feature layers:
  • User-defined Z value: this options allows you to set a constant Z value for all features in the layer. The option is not applicable for surface layers.
  • Drape to layer: this option forces ET Terrain Viewer to obtain the Z value for all features in a layer from the elevation of the surface layer at the same location. A constant offset above the source surface can be set. The option is not applicable for terrain layers.
  • From original shape file: If the Shapefile has Z values (PointZ, PolylineZ or PolygonZ  or Multi-patch).
• Surface layers: The Z values are derived from the original data - pixel value for rasters, Z values of the triangles for the PolygonZ TINs
• Image layers: By default Z values are set to zero. Image layers can be draped to the surface layer.

Extrusion

Extrusion turns points into lines, and lines into walls. The lowest point of the extrusion is the minimum of the terrain layer. The option is not applicable for terrain and image layers.

Z Scale

Z scale can be used to increase the Z values of the layer by multiplying them by the factor entered. The multiplying factor cannot be zero. A multiplying factor of 1 basically negates scaling.

Resolution of Surface layers

You can adjust the level of details for terrain layers. 100% means that the layer is displayed with in its finest details. The higher the resolution, the better is the quality of the layer; the lower the resolution, the better is the rendering performance of the viewer.

ET Terrain Viewer automatically reduces the resolution of large terrain layers - raster or TIN. If your hardware can cope with better details, you can increase the resolution once the layer is added to the project.

The option is applicable to terrain layers only.

Decreasing resolution of large terrains is a slow operation. The lower the desired resolution, the more it takes to simplify the terrain.