Brush2Model: Convolution surface-based brushes for 3D modelling in head-mounted display-based virtual environments

Easy and efficient 3D modelling in virtual environments is an important and unsolved topic. This paper proposes a new modelling approach to tackle this issue. It invents convolution surface-based brushes to directly draw 3D models in head-mounted display-based virtual environments. In order to maximize the efficiency, flexibility, and capacity of our proposed modelling approach, we propose three different skeleton-based convolution surfaces to tackle different modelling tasks: point skeleton-based convolution surfaces for metaball shapes, line skeleton-based convolution surfaces for cylindrical shapes, and polygon skeleton-based convolution surfaces for planar surfaces. Their combination makes 3D modelling more flexible and powerful. The high efficiency is further raised by our developed closed-form solutions for point skeletons, ends of line skeletons, and edges of polygonal skeletons. Different user-friendly sweeping schemes are provided to facilitate intuitive inputs for various complex shape generation. Unlike Google's Tilt Brush, which is used to create disconnected sheet-like surfaces only, our proposed convolution surface-based brushes can produce smoothly blended manifold surfaces, and novice users can easily learn and use them to create various interesting 3D models efficiently.