Auto Trace images in Revit and AutoCAD

Do you want to convert image lines to be used in your 3D modeling software? Import DWG into Revit whether it’s a façade, family profile, or a plan layout.

Follow the steps in this guide to transfer image lines to the edit mode.

A raster image is a collection of clustered, colored pixels. Typical raster formats include JPG, PNG, GIF, TIFF, and BMP. For vector files, formulas are converted into images.

A PDF file can also contain raster images, but because PDFs are unique, they can contain both vector and raster images.

Unlike pixels, which have quality limitations based on the file’s resolution, vector images will retain the same quality no matter the scale or zoom. CAD file types like DWG and DXF are all vector files. Revit can easily read and process these standard CAD vector file formats.

Step 1 – Install Inkscape

Go to the Inkscape website, download and install the software. From the site’s upper toolbar > Download tab > Current Version.

  1. Check Create Inkscape Desktop Icon.
  2. Click Next > Finalize installation process.
trace image in revit - Inkscape to dxf
open inkscape icon

Step 2 – Convert Raster to DWG

Hold down the left mouse button to select the image file and drop it over the Inkscape icon.

  1. Select Rendering Mode: None (auto).
  2. Click OK.
auto trace image in Revit

If you will perform multiple traces and want to save time: Select “Auto” for the Image Rendering Mode, check “Don’t ask again” option, and then click OK.

auto trace image from inkscape to Revit
On the “Trace Bitmap” tab you have the option to change the tracing method.
  1. Select the imported image.
  2. Select “Autotrace” which is optimal for different types of raster image.
  3. Click Apply.

To save it as DXF: Go to the File tab > Save As > click Save as type. Select AutoCAD DXF R14 as the Desktop Cutting Plotter.

Next, we will use the converted lines for a wall profile.

Step 3 – Edit Profile

Start with the creation of a wall.

  1. Go to Architecture tab > Mode panel > click Wall.
  2. Create the wall in the Level 1 view.
import dxf for cnc in Revit
We can edit and apply our CAD lines on that wall using elevations or the 3D viewport.
  1. Open the “North elevation” view in the project browser.
  2. Select the wall in view.
  3. Click Edit Profile.

Learn more about profile editing

Step 4 – Import DWG into Revit

Import CAD lines into edit mode where they will be inserted in magenta.

  1. Go to the Insert tab > click Import CAD.
  2. Drop-down Files of type menu.
  3. Select DXF Files (.dxf).
  4. Select the pattern file.
  5. Click Open.
import dxf for cnc in Revit

Select the lines and rescale (Shortcut: RE) or edit them using Draw and Modify tools from the ribbon. Make sure not to break closed loops to avoid errors when you click Finish Edit Mode.

Import dxf in Revit for CNC

Learn more about importing CAD into Revit

Watch the last chapter of my short video tutorial version of this article to apply materials and configure the wall properties of the CNC panel.

The manual conversion method would be to import the image and then draw directly over it using the Draw and Modify tools. Such a process is time-consuming and tedious, especially for large, complex images like floor plans and detailed views. Automatic and free conversion software are optimal to save a few hours of work.

With this method, we simply provide a file to Inkscape, automatically trace it, and export a DXF/DWG vector file. Import the DWG file directly into Revit in edit mode to use for modeling. The exported DXF/DWG files can be opened in AutoCAD to prepare them for CNC/laser cutting.