Real-time tessellation of terrain on graphics hardware (original) (raw)

A Hybrid GPU Technique for Real-Time Terrain Visualization

2016

Real-Time terrain visualization plays an important rule in multiple popular applications like geographical information systems, computer games, or civil or militar simulators, where hardware tessellation has become a de-facto standard nowadays in the graphic pipeline. Also, post-processing techniques enhance the appearance of the rendered image by applying changes at the pixel level using the fragment shader, without increasing the number of polygons, but they have not been still used in terrain rendering due to different reasons. In this paper, we present a new real-time terrain rendering approach which efficiently combines hardware tessellation and parallax mapping, making parallax mapping compatible with hardware tessellation and terrain rendering. The performance evaluation results show that the proposed scheme improves the performance of real-time terrain rendering applications in regard to the performance yielded when exclusively using hardware tessellation.

Persistent Grid Mapping: A GPU-based Framework for Interactive Terrain Rendering

In this paper we present the Persistent Grid Mapping (PGM), a novel framework for interactive terrain rendering that provides a screen-uniform tessellation of terrains in a view-dependent manner. The persistent grid, which covers the entire screen, is triangulated with respect to the ren-dering capabilities of the graphics hardware and cached in video memory. The GPU maps each vertex of the persis-tent grid onto the terrain. Such perspective mapping of the persistent grid remeshes the visible region of the terrain in a view-dependent manner with local adaptivity. Our algo-rithm maintains multiple levels of the elevation and color maps to achieve a faithful sampling of the viewed region. The rendered mesh ensures the absence of cracks and de-generated triangles that may cause the appearance of visual artifacts. In addition, an out-of-core support is provided to enable the rendering of large terrains that exceed the size of texture memory. PGM algorithm provides high quality images at...

Seamless patches for GPU-based terrain rendering

The Visual Computer, 2009

In this paper we present a novel approach for interactive rendering of large terrain datasets. Our approach is based on subdividing a terrain into rectangular patches at different resolutions. Each patch is represented by four triangular tiles that are selected form different resolutions, and four strips which are used to stitch the four tiles in a seamless manner. Such a scheme maintains resolution changes within patches through the stitching strips, and not across patches. At runtime, these patches are used to construct a level-of-detail representation of the input terrain based on view-parameters. A selected level of detail only includes the layout of the patches and their boundary edges resolutions. The layout includes the location and dimension of each patch. Within the graphics hardware, the GPU generates the meshes of the patches by using scaled instances of cached tiles and assigns elevation for each vertex from cached textures. Since adjacent rectangular patches agree on the resolution of the common edges, the resulted mesh does not include cracks or degenerate triangles. Our algorithm manages to achieve quality images at high frame rates while providing seamless transition between different levels of detail.

Irregular Morphing for Real-Time Rendering of Large Terrain

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2016

The following paper proposes an alternative approach to the real-time adaptive triangulation problem. A new region-based multi-resolution approach for terrain rendering is described which improves on-the-fly the distribution of the density of triangles inside the tile after selecting appropriate Level-Of-Detail by an adaptive sampling. This proposed approach organizes the heightmap into a QuadTree of tiles that are processed independently. This technique combines the benefits of both Triangular Irregular Network approach and region-based multi-resolution approach by improving the distribution of the density of triangles inside the tile. Our technique morphs the initial regular grid of the tile to deformed grid in order to minimize approximation error. The proposed technique strives to combine large tile size and real-time processing while guaranteeing an upper bound on the screen space error. Thus, this approach adapts terrain rendering process to local surface characteristics and e...

Visualization of Large Terrains Made Easy

Visualization, 2001. VIS'01. Proceedings, 2001

We present an elegant and simple to implement framework for performing out-of-core visualization and view-dependent refinement of large terrain surfaces. Contrary to the recent trend of increasingly elaborate algorithms for large-scale terrain visualization, our algorithms and data structures have been designed with the primary goal of simplicity and efficiency of implementation. Our approach to managing large terrain data also departs from more conventional strategies based on data tiling. Rather than emphasizing how to segment and efficiently bring data in and out of memory, we focus on the manner in which the data is laid out to achieve good memory coherency for data accesses made in a top-down (coarse-to-fine) refinement of the terrain. We present and compare the results of using several different data indexing schemes, and propose a simple to compute index that yields substantial improvements in locality and speed over more commonly used data layouts. Our second contribution is a new and simple, yet easy to generalize method for view-dependent refinement. Similar to several published methods in this area, we use longest edge bisection in a top-down traversal of the mesh hierarchy to produce a continuous surface with subdivision connectivity. In tandem with the refinement, we perform view frustum culling and triangle stripping. These three components are done together in a single pass over the mesh. We show how this framework supports virtually any error metric, while still being highly memory and compute efficient.