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Import Solidworks, STEP, Catia, JT and IGES CAD Files in Cinema 4D [New in C4D R20]


Cinema 4D Release 20 now includes native import of Catia, STEP, IGES, Solidworks and JT files so you can easily make use
of CAD data provided by clients. Import CAD formats just like any other file
using File>Open or File>Merge, or by dragging and dropping. All the CAD
formats share the same options dialog, though you can set different defaults
for each format. Besides choosing what type of data to
import, you have detailed control over how to handle the layers, normals, display
color, and materials from the CAD file. You can choose to use the built-in
display colors or assign random colors to easily distinguish each part. If the
CAD file includes materials, you can choose to use those – or you can use the
built-in materials with random coloring to easily distinguish each material. Many
CAD files don’t include built-in materials, and in those cases you can
choose to generate materials based on the display colors. Some JT and STEP
files include a polygon version of the model, and you can import that by
choosing the Source Mesh option. CATIA files with the CGR extension only
include a polygon mesh. Finally the JT format can include three
different models with varying levels of detail, and those can be imported as an
LOD object. In all other cases the NURBs data in CAD files has to be converted to
polygons during import through a process called tessellation. There’s options to
specify how detailed the resulting polygon mesh will be. Low values will
result in a simpler mesh where curved surfaces will appear jagged, while higher
values where we render curves more smoothly but you’re going to get a larger
mesh that’s going to be harder to work with. You can also use the Max Length option
to prevent really long edges that can be difficult to work with and deform in 3D.
Often a CAD file will include very large objects that you need to render smoothly
and millions of tiny bolts which are a waste of polygons because they’re hardly
visible but would require high tessellation to represent their detailed
surfaces. The CAD import includes an option to tessellate objects differently
based on their size. You can specify the sag angle and max
length for small, medium, and large components and use this slider here to
set the threshold for each size. The resulting object hierarchy can be
optimized as well – there’s a very important option to swap the y and z
axis, since many CAD applications use a Z up system. You can also choose to combine meshes into objects based on the
definition in the CAD file, the topology of the object, the display color, or the
layer. Choosing the optimized hierarchy option will remove any extraneous null
objects. The heal and stitch options help to close holes and clean up the
resulting mesh. Heal simply closes holes without modifying the surface, while
stitch will modify the surface in several passes to close more complex
holes. One thing to note about the CAD import is that due to the nature of the
system there’s very few updates to the progress bar as the import is
progressing and files can take five to ten minutes to import depending on the
file size and your tessellation settings. I’ve not yet encountered a CAD file in a
supported format that doesn’t import so just take a break while C4D does the
work and when you come back the model will be ready and waiting. Everything in
the world is built in CAD and with the ability to easily import CAD data into
Cinema 4D Release 20 you’ll have the power to create amazing 3D
visualizations. Make sure to check out all of our tutorials on Cineversity.com
to get a comprehensive view of all of the great features that Cinema 4D
Release 20 has to offer.

8 Comments

  1. Luke Letellier Author

    Very encouraged by the overall feature set…. but 10 minutes to import that little model? i'm a little scared of how long a 30K piece assembly will take.

    Reply
  2. cresshead Author

    thank you! finally a proper overview on CAD import..currently i use 3dsmax step importer, cheap up the model then export to blender cycles for rendering.

    Reply
  3. Eric Liss Author

    This feature is an absolute upgrade for me because of this feature! Currently using Moi3D for conversion to OBJ. I’d like to test this to make sure it does a better job. Moi3D does a fantastic job.

    Reply
  4. Dynamic Author

    Interesting… It looks like MAXON have been (ahem) “heavily inspired” by MoI3D’s CAD to obj algorithm, but chose not to support MoI’s (Rhino) native 3dm file format?? Thankfully, MoI can export to STEP anyway. We’ll see how C4D measures up to MoI for NURB to Poly conversion…

    Reply
  5. Leo Chen Author

    My C4D R20 has crashed when opening some .iges files !
    The Content Brower shows only some .iges and .step files, not all .iges …files !

    Reply

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