remove cells with nodes that contain null data from input field
group DVthresh_null {
Mesh+Node_Data+Iparam &in { /* input field */
xform+nonotify;
nnodes+req;
};
int+Iparam thresh_component; /* component to be thresholded */
Mesh+Node_Data+Oparam out { /* output field */
&xform<weight=-1> => in.xform;
};
method+notify_val+notify_inst upd_thresh_null = "thresh_null";
} ;
DVthresh_null removes cells where the selected component's node data is equal to the null data value; if the null_data flag is not set on the input field no processing is done. You would use DVthresh_null, for example, to improve the performance of the renderer when rendering fields with NULL data. While the renderer will automatically delete NULL data cells, it must do so every time the object is transformed. With DVthresh_null as a data "preprocessor," this overhead is removed.
The input is a reference to a field containing any mesh and Node_Data.
An integer. Sets which Node_Data component to use during the search for NULL data. The component can be scalar or vector.
The output is a new object. It contains the new unstructured Mesh and its new Node_Data contains all data that is not from a deleted cell.