Height fields provide a way of visualizing 2D data in a 3D scene, so that the vertical coordinate on a surface indicates the value of the 2D variable at each point. The most commonly used height field is terrain height, so that the resulting 2D surface provides a visual indication of the terrain surface. However, any 2D variable can be used in VAPOR as a height field.
The variable used as a height field must be consistent with the vertical coordinate in the scene; i.e. the variable values should be between the min and max vertical extents of the data volume. A python script can be easily used to redefine a 2D variable to fit within the desired vertical extents. The HGT variable in WRF data is easily used as a height field; however the ocean depth variable in ocean models should be negated to produce a height field that matches the ocean bottom.
It may also be necessary to adjust the vertical placement of the data (i.e. modify the z-center slider), to ensure that the displaced surface is correctly positioned in the scene.
Height fields may be used in the 2D, Image, and Barbs tabs. The height field variable must be selected and a box must be checked, indicating that the rendering will be displaced by the height field. The refinement level and LOD used in the renderer determine the refinement level and LOD that are used to access the height field data.
