IDynamicCacheLayerManager.DetailsThreshold Property

The threshold to determine the level of detail to use. Values range from 0 to 100, where 100 means always choose coarse data.

[Visual Basic .NET]
Public Property DetailsThreshold As Double

[C#]
public double DetailsThreshold {get; set;}

[C++]
HRESULT get_DetailsThreshold(
  double* threshold
);

[C++]
HRESULT put_DetailsThreshold(
  double threshold
);

[C++]

Parameters
threshold [out, retval]
  threshold is a parameter of type double
threshold [in]
  threshold is a parameter of type double

Product Availability

Remarks

The cache for non dynamic layers is composed of discrete levels of details. Each level of detail corresponds to a specific map scale. In order to draw the cached tiles in the map, the dynamic display has to choose an appropriate level of detail and resample it further in order to scale it to the current map scale (which might be slightly different from the one that corresponds to the given level of detail). For that reason, most given map scales will fall within two levels of detail of the cache. Choosing the coarsest level of detail (the one whose scale is smaller than the map scale) may result in a bit blurry display because of the stretching effect and on the other hand, choosing the more detailed level of detail may lead to too many tiles that are needed to be drawn in the display and eventually degrades performance. For that reason, the dynamic display is calculating a �normalized distance� which is the normalized value of the scale difference between the maps� current scale and the coarse level of detail scale divided by the difference between the coarse level of detail scale and the more detailed level of detail scale.

The threshold determines the normalized value by which the coarse level of detail will be preferred over the more detailed one. By default the threshold value is set to 0.85 which means that as long as the scale difference between the map and the coarse LOD is below 85% of the difference between the scale of the coarse LOD and the finer LOD, the coarse LOD will be chosen over the more detailed one.

In order to favor them more detailed LOD, you should decrease the threshold.

See Also

.NET Samples