About Automatic Placement of Dimension Text
When you create linear and angular dimensions, including dimensions with geometric tolerances, within the zone of the dimensioned edges or entities, the dimension text is automatically centered between the witness lines of the dimensions. Automatic placement of dimension text is possible only when you create linear and angular dimensions in the 2D mode and not for created and modified diameter, radius, true arc length, ordinate dimensions, and all driving dimensions.
If the dimension text overlaps the arrows, the arrows are automatically flipped.
If the dimension text does not fit between the witness lines, it is automatically displayed outside the witness lines, on the side closest to the selected placement point.
If the arrows of such dimensions do not fit between the witness lines, they automatically flip to the outside.
If the dimension is placed outside the zone and the arrows overlap, the arrows flip automatically.
While moving driven linear and angular dimensions, the dimension text automatically snaps to the center about the witness lines of the dimensions.
You can move the dimension text along the elbow of the dimension. When you move the dimension along the elbow, a vertical snapping centerline appears at the default location of the dimension text.
The dimension text flips automatically when you move radial, diameter, or linear driven dimensions. However, if you modify the elbow length or the position of the dimension text relative to its leader, the dimension text does not flip automatically.
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The system uses the value as calculated by the dim_text_gap Detail option to determine the distance for calculation of overlap.
The gap size, or overlap, is calculated using the following formula.
gap size = value of dim_text_gap * value of drawing_text_height
The zone is a theoretical area, the boundaries of which are defined by the boundaries of the edges or entities selected for dimensioning. If you place the dimension outside the zone, the dimension text is not automatically centered.