Free app Penzil lets you sketch in 3D and export to Blender
Sketch in 3D with your stylus, mouse or finger
Penzil is straightfoward to use: you draw onto a plane in 3D space using a pencil tool.
You can adjust the stroke width and colour, and fill closed strokes with a separate colour. Right-clicking lets you move or rotate the canvas, which you can also do via an Autodesk-style viewcube.
An eraser tool lets you erase entire strokes – it doesn’t currently seem to be possible to erase only part – or your can step backwards and forwards through your undo history.
Once a sketch is complete, you can save it or export it to Blender as a .json file.
— Bart Biernacki (@Biernacki) June 26, 2021
A simple-to-use 3D concept sketching tool
That’s pretty much it, but the app is a lot of fun to use, and some of the sketches that early users have produced are reminiscent of – if simpler than – VR sketching tools like Oculus Quill.
Colò says that he was inspired to start working on it after seeing Blender’s Grease Pencil toolset, and wanted to be able to “sketch in 3D on my iPad, on my sofa, without [a] laptop and graphics tablet”.
Penzil doesn’t have a built-in importer for Grease Pencil sketches yet, though you can get them into Penzil via a script available from Colò’s Discord server.
Colò is still developing new features for the app, and is soliciting feedback via the menu option inside Penzil itself and on Twitter.
Penzil is browser-based, and should work on pretty much any desktop or mobile device. It’s free to use.