ArcObjects Library Reference (GeoAnalyst)  

ISurfaceOp.Visibility Method

Performs visibility analysis on a surface based on a set of input observation points.

[Visual Basic .NET]
Public Function Visibility ( _
    ByVal GeoDataset As IGeoDataset, _
    ByVal observers As IGeoDataset, _
    ByVal visType As esriGeoAnalysisVisibilityEnum _
) As IGeoDataset
[C#]
public IGeoDataset Visibility (
    IGeoDataset GeoDataset,
    IGeoDataset observers,
    esriGeoAnalysisVisibilityEnum visType
);
[C++]
HRESULT Visibility(
  IGeoDataset* GeoDataset,
  IGeoDataset* observers,
  esriGeoAnalysisVisibilityEnum visType,
  IGeoDataset** outGeoDataset
);
[C++]

Parameters

GeoDataset [in]

  GeoDataset is a parameter of type IGeoDataset

observers [in]

  observers is a parameter of type IGeoDataset

visType [in]

  visType is a parameter of type esriGeoAnalysisVisibilityEnum

outGeoDataset [out, retval]

  outGeoDataset is a parameter of type IGeoDataset

Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

Remarks

geoDataset

an input Raster, RasterDataset, RasterBand, or RasterDescriptor used to define the z values for visibility calculations and analysis

observers

input FeatureClass or FeatureClassDescriptor containing containing point or line features used as observation points

visType

an esriGeoAnalysisVisibilityEnum specifing the type of visibility analysis to be performed

esriGeoAnalysisVisibilityFrequency the output will only record the number of times each raster-cell location can be seen by the observation points

The observation frequency will be recorded in the Value item in the output Raster's value attribute table.

esriGeoAnalysisVisibilityObservers the output for each cell location will contain a binary-encoded value which can be decoded to identify the observation# of each observation point that can see each Raster cell

The encoded value will be recorded in the Value item in the output Raster's value attribute table. In addition to the standard items, Value and Count, in the value attribute table, a new item named OBSn will be created in the value attribute table for each observer n in the input point dataset. The OBSn item will be assigned a value of 1 if the cell can be seen by observer n, or a value of 0 if it cannot be seen.

esriGeoAnalysisVisibilityFrequencyUseCurvature the output will only record the number of times each raster-cell location can be seen by the observation points

The observation frequency will be recorded in the Value item in the output Raster's value attribute table. It also corrects for earth curvature and refraction.

esriGeoAnalysisVisibilityObserversUseCurvature the output for each cell location will contain a binary-encoded value which can be decoded to identify the observation# of each observation point that can see each Raster cell

The encoded value will be recorded in the Value item in the output Raster's value attribute table. In addition to the standard items, Value and Count, in the value attribute table, a new item named OBSn will be created in the value attribute table for each observer n in the input point dataset. The OBSn item will be assigned a value of 1 if the cell can be seen by observer n, or a value of 0 if it cannot be seen. It also corrects for earth curvature and refraction.

 

See Also

ISurfaceOp Interface