Inventor Fusion from Autodesk is a 3D design and drawing tool for the Mac. Don't let the fact that it's free mislead you; this is a full-featured 3D CAD application that you can use for serious work or even serious play.
Autodesk Inventor Fusion
Inventor Fusion projects start off as standard 2D drawings, using typical 2D drawing and sketching tools. Once you have a 2D drawing ready, you can start transforming it into a 3D drawing by first performing a 2D rendering, where you can shove, push, crimp, and otherwise manipulate the rendering to achieve the desired results. When you're satisfied with the rough 2D rendering, Inventor Fusion will create a full 3D version for you.
Inventor Fusion can have a steep learning curve, but the app comes with video training. There's also a large online documentation repository that includes more detailed videos, webinars, and other useful guides.
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