Loading CAD annotation

Loading CAD annotation into a geodatabase converts it to an annotation feature class. You can load multiple CAD annotation feature classes into the same feature class or create an annotation class for each drawing layer in the CAD file containing text.

• The Import CAD Annotation tool allows the greatest control over the conversion process. You can create annotation classes by layer, apply uniform font properties, reference symbol collections, and link the output feature class to features in another feature class.
• The CAD To Geodatabase tool is a bulk loader. It loads CAD text using presets that you cannot change. It creates an annotation class for each drawing layer containing text.

Specify the map units

You can control the size of the output annotation with the input dataset's spatial reference. The annotation conversion tools use the linear units defined by the map projection to calculate the target font size. When you choose a map projection with units that match the map units of the data frame, the resulting size matches the original CAD text. For example, choosing a coordinate system with linear units in U.S. survey feet generates annotation calculated for a destination coordinate system also set to Feet.

Note:

If you do not define a spatial reference or if it is an unknown coordinate system, the conversion tools use meters as the default linear units to calculate the target font size.

Set the reference scale

Reference scales are used with cartographic workflows that need annotation to maintain a constant size while working on maps at specific scales. If you anticipate these editing requirements, you can utilize the scale box in ArcMap located on the Standard toolbar.

Opening a CAD annotation conversion tool in ArcMap automatically populates the Reference scale text box with the current map scale. For most workflows you do not need to change the default reference scale. If you open the tools from ArcCatalog, setting the reference scale to 1,000 is a generally accepted value that works well for most use cases.

Caution:

After loading annotation into a geodatabase, care should be taken if you modify the reference scale with the Feature Class Properties dialog box in the Annotation tab. Changing this property modifies the display size but it does not rescale the font size.

Rescale the font size

If you need to rescale the font size after loading CAD annotation into a geodatabase, you can use Field Calculator. The font size property is stored in the field named FontSize. The simplest method is to apply a conversion factor to existing values.

For example, to resize annotation from meters to U.S. survey feet, calculate all values with the expression [FontSize]*(1200/3937).

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