Calculating the Size of Annotation Components
Example A
This example explains how the proportion value is calculated for non-Text-height based annotation symbols that have a fixed symbol height larger than the calculated text height and the effect on annotation component sizes due to a change in proportion value.
If you create an annotation symbol with a leader using Fixed type of symbol with a fixed height of 25 on a model with a size of 100, then
Creo Parametric automatically calculates the text height of 1.5 based upon the current model size.
As the symbol size is larger than the calculated text height, the arrow length and leader elbow length are calculated as follows:
Arrow length = 0.6*calculated text height. That is, 0.6*1.5=0.9
Leader elbow length = 2.5*arrow length. That is, 2.5*0.9=2.25
On completing the creation of the symbol, that is, on clicking OK in the Custom Drawing Symbol dialog box, the proportion of the symbol is automatically calculated as follows:
Proportion = Arrow length/symbol height. That is, 0.9/25 = 0.036.
In the Custom Drawing Symbol dialog box that opens when you right-click a symbol and click Properties, the current proportion appears as 0.036 in the Proportion box.
Change the value in the Proportion box to 0.02. The new arrow length is calculated as proportion*symbol height, that is 0.02*25=0.5 and the new elbow length is calculated as 2.5*arrow length, that is 2.5*0.5=1.25.
Example B
This example explains how the proportion value is calculated for non-Text-height based annotation symbols that have an editable symbol height smaller than the calculated text height and the effect on annotation component sizes due to a change in the symbol height.
If you create an annotation symbol with a leader using a Variable-Drawing Unit type of symbol with a symbol height of 0.5 on a model with a size of 100, then
Creo Parametric automatically calculates a text height of 1.5 based upon the current model size.
As the symbol size is smaller than the calculated text height, the arrow length and leader elbow length are calculated as follows:
Arrow length = 0.6*symbol height. That is, 0.6*0.5=0.3
Leader elbow length = 2.5*arrow length. That is, 2.5*0.3=0.75
On completing the creation of a symbol, that is, on clicking OK in the Custom Drawing Symbol dialog box, the proportion is calculated as follows:
Arrow length/symbol height, that is 0.3/0.5=0.6.
However, if you change the symbol height to 25 before completing the creation, then the symbol size becomes larger than the calculated text height, and the arrow length and leader elbow length are calculated as follows:
Arrow length = 0.6*calculated text height. That is, 0.6*1.5=0.9
Leader elbow length = 2.5*arrow length. That is, 2.5*0.9=2.25
If you confirm the symbol creation at this point, the proportion is automatically calculated as follows:
Arrow length/symbol height, that is 0.9/25=0.036
Again, if you do not complete the symbol creation and change the symbol height once again to 50, then the symbol size is still larger than the calculated text height.
The arrow length does not change because the calculated text height does not change.
The leader elbow length does not change because the arrow length does not change.
Now if you complete the creation of a symbol, that is, on clicking OK in the Custom Drawing Symbol dialog box, the proportion is automatically calculated as arrow length/symbol size, that is 0.9/50=0.018.