This article describes the process of cleaning AutoCAD drawings and preparing linework for importation into 3ds Max and how doing so properly can allow the user to turn linework into 3d models in the shortest amount of time possible. In this article you will see how good preparation of linework in AutoCAD can allow the 3ds Max user to model many complex scene elements in just a few seconds ...

At this point, we will look a little farther into this preparation process that uses the loft/sweep method by looking at how a drawing was arranged for another project.

In addition there are numerous lines in the top left corner that were used to help construct some of the more complex trim features positioned on the walls. There is also a copy of each window and door off to the side which are used as a guide to build each type. These windows and doors can be built in AutoCAD or 3ds Max, but lining up a single copy of each type allows you to build these objects in an assembly line fashion. Finally, notice numerous vertical and horizontal lines positioned around each elevation. These are simply guides with which to cut out the 1-inch thick grout lines found throughout all the walls. Whether you use the Boolean or Edit Poly method to create this feature, you will need lines with which to guide your creation. These same types of lines should also be created to help guide the placement of each window and door. So after a single copy of the windows and doors are created, this linework can be imported and used to position each copy properly along the length of its respective wall.

Once they were placed properly along the length of the walls using these lines, we needed to refer back to the AutoCAD drawings to determine the height of the windows and doors off the ground. Once they are in their final position, we can just explode all of these groups we copied and use the Boolean feature to subtract these objects that represent the volume of the windows and doors, from the lofts, thereby leaving behind a void in which those windows and doors are shown.
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Source: 3dats.com