About Annotation Component Sizes
The size of the following annotation components is driven by annotation text height or symbol height.
Arrow length
Leader elbow
Witness line offset
Witness line delta
Flipped arrow line length
Annotations in which the size of its components is driven by the height of the annotation text are text-height based annotations. Annotations in which the size of its components is driven by the height of the symbol are non-Text-height based annotations. However, if the symbol height is greater than the calculated text height then the component size is driven by the text height.
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The Variable-Text Related type of symbols are text-height based annotations.
The Fixed, Variable-Model Units, or Variable-Drawing Units type of symbols are non-Text-height based annotations. The height of a symbol depends on the definition of the symbol.
Creo Parametric updates the size of the annotation components according to the current proportion whenever you modify the annotation text height or symbol height.
In the Custom Drawing Symbol dialog box the Proportion box displays the value of the Proportion attribute.
In Variable-Text Related type of symbol the default proportion is 0.6 and the Proportion box in the Custom Drawing Symbol dialog box cannot be edited. When you modify the text height or symbol size, Creo Parametric recalculates the proportion and updates the annotation component sizes according to the current proportion.
In non-Text-height based annotation symbols (Fixed, Variable–Drawing units, and Variable–Model Units), when defining a symbol the proportion is not defined. The Proportion box is empty and cannot be edited. After the definition of a symbol is complete, a proportion value is displayed in the Proportion box which can be edited. If you modify the value, Creo Parametric updates the size of the annotation components accordingly.