How to Draw 3D Shapes on Touchscreens Using Your Fingers

A method for creating 3D objects in design software by simply dragging your finger across a touchscreen, allowing the shape to grow in real-time as you move.

What it covers

This patent describes a way to make 3D modeling software responsive to touch inputs. When a user selects a tool and drags their finger across a screen, the software interprets that movement as a path for a new 3D object. As the finger moves, the system calculates and renders the object's geometry instantly. It specifically uses mathematical techniques like cubic b-splines and Catmull-Clark subdivision surfaces to turn a simple finger swipe into a smooth, complex 3D shape.

What it doesn't cover

• —Does not cover 3D modeling using traditional mouse and keyboard inputs.
• —Does not cover importing pre-existing 3D files or scanning objects into the software.
• —Does not cover non-real-time modeling where the shape only appears after the gesture is completed.
• —Does not cover gestures that are not specifically mapped to the creation of new geometric forms.

The clever bit

The system uses the finger's path to generate 'input curves' on the fly, which then act as a skeleton for a mesh that is instantly smoothed into a 3D surface using subdivision algorithms.

Why it matters

Before this, 3D modeling was largely restricted to desktop computers with precise mouse control. By enabling intuitive, touch-based creation, this technology helped move professional design tools like Autodesk's Fusion 360 onto tablets and mobile devices, making 3D design more accessible to students and mobile professionals.

Real-world examples

• 1.Autodesk Fusion 360 mobile app
• 2.iPad-based 3D sculpting and modeling apps
• 3.Touch-enabled CAD interfaces