Article

Real-time rendering high-quality vector data on 3D terrain

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

In the 3D geographic information systems (GIS), it is necessary to overlay 2D vector data on a 3D multi-resolution terrain model. This paper presents a precise and efficient texture-based overlaying algorithm. It generates vector textures from cascaded view-depended cameras to improve the utilization of texture pixels. The strategies of both depth splitting and screen space dividing are further adopted. All steps are based on programmable GPU pipeline. It runs in real-time and is suitable for displaying large-scale terrain with LOD algorithms.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... In recent years, with the continuous development of computer technology and geographic data acquisition method, and the deepening of GIS applications, more and more people are demanding to deal with problems in real three-dimensional space (Li et al. 2011). In the field of 3DGIS, 2D vector data is still an indispensable data type. ...
... However, texture aliasing can occur at steep terrain because of the different resolutions of vector textures. Li Rong et al. (Li et al. 2011) used depth segmentation and screen space segmentation to cut up the scene volume and proposed a multi-cascade drawing method, but the efficiency was low and the rendering frame rate was not high yet. On the whole, in the most common multi-resolution 3D terrain, the traditional several types of vector data fusion rendering methods usually have a large amount of computation and cannot achieve a better fusion effect. ...
Article
Full-text available
This paper presents a viewpoint-related fusion method of massive vector data and 3D terrain, in order to superpose the massive 2D vector data onto the undulating multi-resolution 3D terrain precisely and efficiently. First, the method establishes an adaptive hierarchical grid spatial index for vector data. It will determine the geographic spatial relationship between vector data and the tiles of 3D terrain in the visible area; secondly, this method will use the improved sub-pixel graphics engine AggExt to generate textures for vector data that has been bound to terrain tiles in real time; Finally, considering that a large amount of vector data will generate a lot of 2D textures in the computer memory, the method should release the “expired” vector textures. In this paper, in order to take into account the real-time convergence and the smooth interactivity of 3D scenes, this method will adopt a multi-threading strategy. The experimental results show that this method can realize the real-time and seamless fusion of massive vector objects on the 3D terrain, and has a high rendering frame rate. It can also reduce the aliasing produced by traditional texture-based methods and improve the quality of vector data fusion.
Chapter
Those basic geometric graphs such as lines and polygons are the main representations used by 3D rendering methods of vector map at present. It is so simple that strictly limited map feature information has been transferred. Consequently, an extended rendering method based on the shadow volume stencil theory is presented, which allows real time symbolical overlay of vector map on terrain. Firstly, the basis of vector data visualization based on stencil shadow volume theory has been reviewed. Secondly, in order to improve visualization effect, the cartographic symbolization of vector map, i.e. roads, has been dedicated, which includes smooth border with rounded caps, outlines and overlaps. Finally, the experiment shows that real time displaying of vector map on terrain has been achieved, and the visualization effects have been improved by cartographic symbolical overlay.
Conference Paper
In order to overlay multiscale 2D electronic map in the 3D virtual geographic environment, this study presents and implements symbolic method in 3D API for the different types of feature, studies visualization of vector data based on the sphere, and discuss a number of issues need to be resolved. It proposes the way of multiscale expression based on multiscale topographic map and achieves fast expression and organization of multiscale data in 3D space through multi-thread technology and memory pool. It uses frame buffer object technology to generate symbolic vector data texture in real-time, and implements visualization of vector data in 3D terrain by multi-texture technology. Finally, this paper verified the feasibility of these methods by experiments.
Article
The hybrid geometry information system which can process vector and terrain data at the same time has become a hot. And one of the key problems is how to render complex vector data over multi-resolution terrain. A key data structure and associated algorithm for the combined display of multi-resolution 3D terrain and 2D curve feature were proposed. Then a performance analysis was made and a conclusion is given.
Article
This paper presents a texture-based algorithm for vector data display that is able to precisely and efficiently overlay traditional 2D vector data on a 3D multi-resolution terrain model. By the algorithm, depending on the view to the scene first, a perspective projection is created, to match the currently visible range of the terrain. Then the projection is used to generate the texture on-the-fly with the texture coordinates calculated on GPU. The quality superior to standard texture mapping can be achieved by using the view-dependent perspective projection, for improving the availability ratio of texture pixels. In addition, since the algorithm is independent of the underlying terrain geometry, it is suited to work with terrain LOD algorithms and image pyramid.
Article
In geographical information systems (GIS) vector data has important applications in the analysis and management of virtual landscapes. Therefore, methods that allow combined visualization of terrain and geo-spatial vector data are required. Such methods have to adapt the vector data to the terrain surface and to ensure a precise and efficient mapping. In this paper, we present a method that is based on the stencil shadow volume algorithm and allows high-quality real-time overlay of vector data on virtual landscapes. Since the method is a screen-space algorithm it is per-pixel exact and does not suffer from aliasing artifacts like texture-based techniques. In addition, since the method is independent of the underlying terrain geometry, its performance does not depend on the complexity of the data set but only on the complexity of the vector data.