Procedural content creation in VR

Abstract

3D content creation for virtual worlds is a difficult task, requiring specialized tools based on a WIMP interface for modelling, composition and animation. Natural interaction systems for modelling in augmented or virtual reality are currently being developed and studied, making use of pens, handheld controllers, voice commands, tracked hand gestures like pinching, tapping and dragging mid-air, etc. We propose a content creation approach for virtual reality, placing a focus on making procedural content generation (PCG) intuitive and generalizable. Our approach is to start with a library of 3D assets, with which the user populates an initially empty world by placing and replicating objects individually. The user can then construct procedural rules to automate this process on the fly, creating abstract entities that behave like a block of objects while still being treated and manipulated like other singleton objects. To this end, we design a rule system for procedural content generation adequate for virtual reality, including nested object replication, relative placement and spacing, and randomized selection. We then design and prototype a natural interaction model for virtual reality suited to this rule system, based on two-handed object manipulation, controller input and user voice commands. A prototype of this interaction model is built, and finally, a former user evaluation is conducted to assess its viability and identify avenues for improvement and future work.