Scientists and geologists have made the transition from traditional 2D GIS data.And today they are using three dimensional GIS data for better understanding about the geography of any place. The 2D data had two defining dimensions, x, and y, but a third dimension z has now been added to generate 3D GIS data. The introduction of the third dimension now offers x, y, and z, three types of data thereby capturing much more information than 2D data. What does the Z value represent and why is it so important? The introduction of Z value has added more versatility to data as it can capture a wider range of information, every bit of which is useful for understanding the geographical features in a much better way.
Z value does not have any particular significance asit relates to real-world elevation values that one cannot capture effectively in two-dimensional models. The geological depth of any place or the height above sea level are the most common dimensions reflected in Z value, but there is enough flexibility to use it for representing any other dimensional aspect as there is no fixed rule. You can use Z values in your way to represent many more things such as the suitability of a location, chemical concentrations or use it for representing the hierarchical values. To know more about three dimensional GIS data, keep reading.
Feature data 3D
When you are handling data related discrete objects, it is known a Feature data. The 3D data or information of each object remains stored within the geometry of the feature. For each x, y location, three-dimensional feature data can support several z values. If you look at a vertical line, you will find one upper vertex and another lower vertex with the same 2D coordinate, but the z value of each is different.
A 3D multipatch building is another example of 3D feature data. In this model, you will find that the foundation, interior floors, and roof have the same 2D coordinate but the z values are different. However, if you look at the 3D position of an aircraft or a walking trail up a mountain track, for each x, y location there would a single z value.
The value of heights in an area constitutes the Surface data, and you can store the 3D information for each location in that area as cell values or deduce it from a triangulated network of several 3D faces. Surface data supports a single z value corresponding to each x, y location; they often refer to it as 2.5 D data. A typical example is a height above the sea level that consists of a single data only. A 3D surface model represents the features digitally in a three-dimensional space regardless whether the data is real or hypothetical.
Gas deposits under the earth, an urban corridor, a landscape and a network of proper depths that aid in determining the water table is typically by a 3D surface model.
July 25, 2018