How Terrain Pyramid Level Definition (3D Analyst) works

The Add Terrain Pyramid Level tool adds new pyramid level(s) to an existing terrain dataset.

The Pyramid Level Definition window defines the z-tolerance or window size and reference scale of one or more pyramid levels to be added to the terrain dataset.

The z-tolerance or window size can be specified as a floating point value. The reference scale must be provided as a whole number (e.g., a value of 24,000 represents a scale of 1:24,000)

The values are given in space-delimited pairs: one pair for each pyramid level. A pyramid level of 2.5 and a scale threshold of 1:10,000 would be entered into the definition window as: 2.5 10,000.

The example in the table below demonstrates setting terrain pyramid levels for a z-tolerance pyramid type.

Terrain Pyramid Definition

Pyramid Level

Z - Tolerance

Reference Scale

Definition Window Entry

1

0

1:1000

0 1000

2

1

1:5000

1 5000

3

2.5

1:10000

2.5 10000

4

5.0

1:25000

5 25000

5

10.0

1:50000

10 50000

Terrain Pyramid Definition

Using the settings above, the full resolution data is used in map displays up to a scale of 1:1,000. Between display scales of 1:1,000 and 1:5,000, only the data necessary to achieve an approximate vertical tolerance of 1.0, relative to the full-resolution data, is used. Between 1:5,000 and 1:10,000, only the data necessary to achieve an approximate vertical tolerance of 2.5, relative to the full-resolution data, is used. Between 1:10,000 and 1:25,000, a tolerance of 5 is used. For any scale smaller, a tolerance of 10 is used to display the terrain data.


6/10/2013