Image Overlapping Technique without Model for Large LoD Terrain Based on GPU

Abstract

There are many difficulties in image overlapping in 3D terrain of dynamic LoD quad tree model, it will cause gaps between terrain tiles and images if both of them are expressed independently. This paper breaks through the LoD mesh difficulties, and realizes image overlapping based on GPU programming without modeling. It establishes different texture coordinate transformational relationships in GPU to realize seamless expression between terrain texture and overlapping image based on setting terrain vertexes with global unified texture coordinate. The affine transformation is adopted to solve the difficulty of multiple spatial nonlinear transformations aiming to the interaction of image overlapping, and also to solve the non-synchronous problem of texture coordinate in interaction. At last, the conclusion may be achieved. Image overlapping technique in LoD terrain without modeling based on GPU is a typical case of render technology to solve application difficulties, the realization is simple, efficient and steady which only faces to single terrain tile. This research will greatly enhance the ability of Digital Earth, which completely clear an important technical barriers and promote the applications in GeoDesign.