Annotation - Filtering Annotation

The Filter option allows you to filter overlapping annotations based upon user-defined priorities.  This option is available for height annotation or all annotation, but the options produce different results.  You should also note that the filtering process will be affected by the current view scale and the higher the scale, the larger the text appears to be.

When filtering height annotation you need to set the priority of heights that are attached to points.  This is carried out in the Heights tab of the code prefixes dialog.  The Priority drop box allows you to set the priority for the height.  When the priority is set to Always, the height will never be filtered.  Alternatively, you can set a value of 1 through to 9, 1 being the lowest and 9 the highest.  A height with a priority of 9 overlapping a height with a priority of 1 will filter the latter.

After you have selected the Filter option, the dialog box shown below will be displayed. 

This allows you to control what to do with heights of the same priority and the final action taken.  The Filter on Same Priority check box allows you to control what happens when two heights have the same priority.  If checked, filtering will take place and the second height will be disabled.  The Place Points on Select List check box allows you to add all points where height filtering would take place to the select list.  In this case, the heights are not disabled and it is up to you to explore the model and move any overlapping text.  The Clear Select List option allows you to remove all points from the select list before filtering takes place and is only enabled if the previous check box is ticked.  The Max Height Diff check box allows you to not filter heights that overlap where the height difference between the wo points is greater than the value specified field.

Before Height Filtering	After Height Filtering

When filtering all annotations, the priority settings are ignored.  After the option is selected, all displayed annotation is analysed and any point that has annotation that overlaps with annotation from another point will be added to the select list.  Therefore, if you have two items of annotation that overlap, you will have two points on the select list.  Note that if overlapping annotation is found, the select list will be cleared before the points are added.  If no overlapping annotation is found, an error beep will sound and the select list will remain as it was.