Datasheet

4
c h a p t e r 1: PREPARING DRAWINGS IN CAD OR BIM FOR ENHANCEMENT ■
The first time you go through this procedure, you’ll need to create a raster print
driver in order to export single-pixel-width lines from AutoCAD. In addition, you’ll
create a custom “paper size” (actually specified in pixels) and create a custom plot
style to properly export lines as pixels. Once these drivers are set up, you can use them
indefinitely to convert vector drawings into raster images.
You’ll also need to make a test plot in order to configure the LISP program to
automate the creation of images from each layer in your CAD drawing. The last pre-
paratory procedure is reassembling all image layers exported from the LISP program
within AutoCAD into a smart object in Photoshop (see Figure 1.1).
Figure 1.1 Converting an AutoCAD drawing to a Photoshop smart object
Cleaning Up Drawings
The data of CAD drawings must be in a suitable form before it can be used success-
fully in Photoshop. It is therefore important to follow a few basic cleanup guidelines
when preparing CAD drawings for use in Photoshop:
F• ollow “clean” drafting practices so that end points of entities snap together
precisely.
V• erify that entities are on the correct layers.
S• implify layers into human-readable form; the layers you transfer into Photoshop
are for your reference and do not need to adhere to a standard CAD layer-nam-
ing convention.
P• urge any unused layers and blocks (because blocks can trap layers).
C• ut away and erase any nonessential areas of the drawing that you won’t be
enhancing in Photoshop.
E• rase any filled or hatch areas, symbols, title blocks, or dimensions you don’t
want to appear in Photoshop.
S• implify the drawing as much as possible to maximize readability.
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