About Display of Dimension Text
If the dimension text of a linear or angular dimension overlaps the dimension leader line, a break is automatically added to each such dimension leader line around the dimension text. Each line of dimension text is checked for dimension leader line overlap, and if required, a break is added to the leader line.
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You cannot change the size of the automatically added breaks.
Similarly, if the dimension text of a linear or angular dimension overlaps its witness line, a break is automatically added to the witness line at the actual intersection with the dimension text. However, a witness line will break around dimension text that is a part of the same dimension and not break around dimension text that belongs to another dimension.
If a dimension has large additional text, such that not every line of text overlaps the witness line, then breaks are added to the witness line for each overlapping text line.
If the dimension text overlaps the dimension’s leader as well as the witness line, then both leader and witness lines will have appropriate breaks at the actual intersections. This does not impact the display of the leader arrow.
In 3D mode, if you move angular dimension text outside of the dimension’s witness line, a gap is created between the witness line extension and the dimension text.
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In legacy drawings the dimension leader and witness lines do not break at the overlapping dimension text. However, if you modify the dimension by moving the dimension text, breaks are added at the actual intersections of the dimension text and dimension leader and witness lines.
Following example shows breaks that are automatically added to the dimension leader and witness lines at the overlapping dimension text.