Walkthroughs of complex environments using image-based simplification

Abstract

We present an image-based technique to accelerate the navigation in complex static environments. We perform an image-space simpli cation of each sample of the scene taken at a particular viewpoint and dynamically combine these simpli ed samples to produce images for arbitrary viewpoints. Since the scene is converted into a bounded complexity representation in the image space, with the base images rendered beforehand, the rendering speed is relatively insensitive to the complexity of the scene. The proposed method correctly simulates the kinetic depth e ect parallax, occlusion, and can resolve the missing visibility information. This paper describes a suitable representation for the samples, a speci c technique for simplifying them, and di erent morphing methods for combining the sample information to reconstruct the scene. We use hardware texture mapping to implement the image-space warping and hardware a ne transformations to compute the viewpoint-dependent w arping function.

Simplifying complex environments using incremental textured depth meshes

“…Flat images [Aliaga 1996;Debevec et al 1998;Maciel and Shirley 1995;Shade et al 1996;Schaufler and Sturzlinger 1996] are mapped onto planar projections, but only display correct perspective when viewed from the location where the image was created. Textured depth meshes (TDMs) Darsa et al 1998;Sillion et al 1997;Wilson et al 2001] replace the planar projections used by flat images with simplified meshes created from sampled depth values. TDMs are extended to handle multiple layers in [Decoret et al 1999].…”

“…The first one is based on standard TDMs Darsa et al 1998;Sillion et al 1997;Wilson et al 2001], where the scene was subdivided into uniform-sized cells and a single panoramic TDM was computed for each cell. These cells were kept small in order to minimize the severity of skins.…”

“…The time required to render these representations is mostly a function of imagespace resolution and is independent of scene complexity. Many algorithms and systems have been proposed that approximate portions of environments with image-based impostors for faster display Aliaga 1996;Aliaga and Lastra 1999;Chang et al 2001;Darsa et al 1998;Decoret et al 1999;Maciel and Shirley 1995;Schaufler and Sturzlinger 1996;Shade et al 1998;Shade et al 1996;Sillion et al 1997;Wilson et al 2001].…”

“…Parallax effects can be added to flat images by triangulating the depth values associated with the environment map from each viewpoint. The resulting triangles can be warped using texture mapping hardware [Sillion et al 1997;Darsa et al 1998;Decoret et al 1999;. Moreover, Z-buffer hardware can be used for resolving occlusions and rendering interactively.…”

TexMol: interactive visual exploration of large flexible multi-component molecular complexes

“…Large scale environment visualization through images was shown in [2,28,22,15]. Better depth maintenence was shown in [8,19]. In [12], an image based rendering algorithm is given which depends on lighting conditions.…”