Subscription Bonus Pack 2: A closer look at PDF underlays

After installing the AutoCAD 2009 Subscription Bonus Pack 2, you’ll find PDF listed as one of the available file types in the External Reference Manager. You can attach a PDF file as an underlay to a drawing in the same way that you attach other externally referenced files including DWG, DWF, DGN, and images. You can also use the new PDFATTACH command, available on the Subscription tab in the ribbon, or the command line version, -PDFATTACH. In either case, you’re prompted to select the PDF file and specify typical attachment information including path type, insertion point, scale, and rotation.

After you’ve attached a PDF file to the drawing, you can control the display of the PDF frame, control the display of layers, snap to key points, adjust display properties, and clip the PDF attachment.

PDF Frame
A new system variable, PDFFRAME, enables you to turn the PDF frames on or off. They must be turned on for the PDF attachment to be selectable.

PDF Layers
The new PDFLAYERS command enables you to control layer visibility for the select PDF attachment if the layer information was included in the PDF during the plot process.

Object Snaps
Snap to key point on PDF geometry using familiar object snaps. You can control this behavior, which is enabled by default, with the new PDFOSNAP system variable.

PDF Adjust
You can modify the appearance of a PDF attachment using the new PDFADJUST command, available on the Subscription tab of the ribbon. A command line version, -PDFADJUST, is also available. The controls include Fade, Contrast, and Monochrome and the changes you make affect the plotted output. Adjusting these settings does not alter the original file and does not affect other instances of the PDF underlay in the drawing. All of these settings, as well as an additional control to automatically adjust the underlay colors so they are visible against the drawing background color, are also available in the Properties palette for a selected PDF attachment.

PDF Clip
The new PDFCLIP command (available on the Subscription tab of the ribbon) enables you to clip the PDF attachment by specifying a rectangular or polygonal clipping boundary. You can turn clipping on and off, as well as delete it, using right-click menu options and you can edit the boundary with grips.