Remove data above and below min/max threshold levels, by setting to NULL.
| in | Mesh+Node_Data | input field for threshold of Node_Data |
| minimum | double | lower threshold level |
| maximum | double | upper threshold level |
| out | Mesh+Node_Data | output field with thresholded Node_Data and original Mesh |
The threshold macro removes all values in the Node_Data of a field above a maximum value, and below a minimum value, by setting those values to NULL. The macro operates on any type of Node_Data of a field, and the output must be recombined with the mesh, to get a Field data structure. The macro also includes a UI Macro to provide a simple interface via dials to the minimum and maximum values.
in
The input Field for the threshold macro. The lower-level module ThresholdNodeData is used, inside the Functional Macro Threshold, to threshold the Node_Data of any input field, and to then recombine it with the original Mesh (if present).
minimum
A member of the ThresholdParams paramter block group, this double value is used to select the lower threshold level for the module.
maximum
A member of the ThresholdParams parameter block group, this double value is used to select the upper threshold level for the module.
out
The output field for the threshold macro. This contains the thresholded Node_Data combined with the original Mesh (if present).
The User Macro threshold combines the Functional Macro Threshold with the UI Macro Threshold UI, via the use of the common parameter block ThresholdParams, to provide a usable macro in the visualization library.
An example application ThresholdEg is provided, which uses the AVS/Express sample data file hydrogen.fld, to display a thresholded orthoslice.
iac_proj/thresh/thr_macs.v contains the Functional Macro Threshold, the User Macro threshold, the UI Macro ThresholdUI and the Example Application ThrsholdEg.
The ThresholdMacs library inherits its process. As this library contains no procedural code, the process is not important. The low-level ThresholdNodeData module, executes under the process specified in its library, not the process defined in the high-level library.
Nick Trout Ian Curington Paul G. Lever International AVS Centre Manchester Visualization Centre Manchester Computing University of Manchester Oxford Road Manchester UK M13 9PL
ThresholdParams, ThresholdNodeData, Threshold, and ThresholdUI.
DVthreshold, DVthreshold_cell, DVthresh_null.