Distance Field based Haptic Rendering of Scattered Oriented Points

Abstract

This work is aimed at rendering of an object described by a scattered, oriented point set data without explicitly finding the bounding surface. We propose a proxy based rendering technique on a distance field based representation of the object in a regular 3D grid of voxels. Our method initially finds a 3D indicator function in the grid of voxels from the available point set data through sphere packing. The indicator function is further used to find the implicit potential function (distance field) in the voxel grid by iteratively moving the bounding surface of the object inward till all the voxels are covered. Our algorithm uses a gradient descent based minimization of the distance between HIP and proxy during the penetration of HIP in the object. The rendering algorithm interpolates the distance at the proxy point from the neighboring voxels in order to find the gradient for the purpose of moving the proxy. We experimented on a large set of scattered point set data and could effectively render them using a three degree of freedom haptic device.