• TechNotes
• How to Superimpose a 2D Floor Plan onto a 3D Model

How to Superimpose a 2D Floor Plan onto a 3D Model

This topic demonstrates a way to place a 2D linear drawing into the 3D model at the exact vertical position of the Cut Plane from which that 2D Floor Plan View was generated. This can help you to compare the current 3D model with its 2D representation. The steps are the following:

1. On the Floor Plan, go to the Story whose 2D plan you wish to superimpose on the model.

2. Switch to the Layer Combination, Model View Options Combination etc. of your choice. Also check the Floor Plan Cut Plane setting.

See Setting up a View in ArchiCAD Help.

Note: It is a good idea to actually save a View with these settings in case you wish to do these steps again later when the Project has changed.

3. Using the File > Save as command, save the Floor Plan as a DXF or DWG file to a location of your choice.

4. Open this saved DXG/DWG file using the File > Libraries and Objects > Open Object menu command.

When you open the DXF/DWG file, the lines will be created as 3D lines in a horizontal X-Y plane in the resulting Archicad Library Object. You can go and check the 3D View of the Library Object to see it in 3D.

5. Save the Library Object under a new name.

6. Go back to the Floor Plan, and go to the Object Settings Dialog. The Object you just saved will be the selected Object.

7. Set the vertical height at which the Object will be placed into the Project. This should be the Level of the Floor Plan Cut Plane used with the View from which the DXF/DWG file was saved.

8. Click OK to accept the changes. In the Floor Plan, place the Object. After placement, you may need to move it around a bit so that the 2D of the model and the 2D of the Object exactly overlap.

9. Switch to the Layer Combination used to view Sections/Elevations or Model Views. Also, make sure to set all needed element types visible in the View > Elements in 3D view > Filter Elements in 3D dialog box.

See Filter Elements to Show in 3D in ArchiCAD Help.

10. In this same dialog box, select the Stories you wish to display. You probably do not want to display Stories higher than the Story of the 2D overlay.

See Defining Story Display in 3D in ArchiCAD Help.

11. Display the model in 3D.

Note: The 3D Window must be set to OpenGL mode with the Shaded View option. The reason for this is that with the Internal 3D Engine, 3D lines are not shown.

See 3D Engines and 3D View Modes in ArchiCAD Help.

The 2D Floor Plan is now shown in its correct spatial position, superimposed over the 3D Model.

For even better comparison, you can apply a 3D Cutting Plane to the 3D Model at the height of the superimposed 2D drawing. This is useful if you want to make exact comparisons. To do this: - go to View > Elements in 3D > 3D Cutting Planes. You will probably see where the 2D linear Object is in the model (point of red arrow).

See 3D “Cutaway” Sections in ArchiCAD Help.

- Create a horizontal Cut Plane just above the height of the 2D Object (e.g. 1 cm or 1” above it). Make sure that the Cut Plane does not cut the 2D Object off the model in case they are at exactly the same height. For this use the Z coordinate field.

- Click OK to accept these changes. Also, make sure to check the View > Elements in 3D > 3D Cutaway option to activate the cut in 3D. The model is now cut at the exact height of the 2D superimposed Object.

Category3dModeling