Interactive Minimal Latency Laser Graphics Pipeline

Abstract

We present the design and implementation of a ”Laser Graphics Processing Unit” (LGPU) featuring a proposed re-configurable graphics pipeline capable of minimal latency interactive feedback, without the need of computer communication. This is a novel approach for creating interactive graphics where a simple program describes the interaction on a vertex. Similar in design to a geometry or fragment shader on a GPU, these programs are uploaded on initialisation and do not require input from any external micro-controller while running. The interaction shader takes input from a light sensor and updates the vertex and fragment shader, an operation that can be parallelised. Once loaded onto our prototype LGPU the pipeline can create laser graphics that react within 4 ms of interaction and can run without input from a computer. The pipeline achieves this low latency by having the interaction shader communicate with the geometry and vertex shaders that are also running on the LGPU. This enables the creation of low latency displays such as car counters, musical instrument interfaces, and non-touch projected widgets or buttons. From our testing we were able to achieve a reaction time of 4 ms and from a range of up to 15 m.