One-to-Two Digital Earth

The digital Earth framework is a multiresolution 3D model used to visualize location-based data. In this paper, we introduce a new digital Earth framework using a cube as its underlying polyhedron. To create multiresolution, we introduce two types of 1-to-2 refinement. Having a smaller factor of refinement enables us to provide more resolutions and therefore a smoother transition among resolutions. We also suggest two indexing methods specifically designed for quadrilateral cells resulting from 1-to-2 refinement. We finally discuss the equal area spherical projection that we are using in this framework to model the Earth as a sphere partitioned to equal area cells. Fig. 1. (a)A cube (b) The cube after applying dual 1-to-2 refinement three times. (c) The refined cube is projected to the sphere using an equal area spherical projection. (d) The spherical cube at a high resolution. (e)The resulting spherical polyhedron is textured using a blue marble image. The blue marble texture is taken from [1].