Effective GPU-based synthesis and editing of realistic heightfields

Giliam de Carpentier

Thesis abstract:

Computer games are expected to get evermore richer and detailed with each new generation of game consoles. Development of content for these game worlds is increasingly time consuming and, thus, would benefit from more effective tools. However, game level designers still work in almost the same way as five or ten years ago, with tools that are typically crude and inflexible. Therefore, investigating ways to improve the workflow and technology available to a level designer is both very necessary and promising.

This dissertation investigates techniques to support the creative process of terrain design, which would improve both speed and quality. This research is limited to the most common type of geometry used for large open terrains, called heightfields, defined by horizontal regularly-spaced grids of height samples. To improve results, the applicability of several ideas from other design applications is discussed and several new extensions to existing procedural terrain generation algorithms are given. A comprehensive presentation of underlying theories and related work in these fields is provided. To improve the speed of terrain tools, ideas are explored that use today’s powerful graphics cards not only to render 3D terrain, but also to perform actual terrain manipulations. These ideas have been incorporated into a custom testbed editor, together with a number of complex tools that use this new pipeline to their advantage.

Details and results of this pipeline and the implemented tools are given. By executing the terrain manipulating algorithms on the graphics card instead of on the CPU, a noticeable speedup is achieved in practice, allowing for better interactive editing. To this purpose, an existing terrain rendering technique has been implemented in the testbed and further optimized for the specific demands of terrain editing. It is concluded that the proposed combination of common and novel heightfield editing techniques represents a valuable step towards overcoming the limitations of current terrain editing applications, by simultaneously improving quality, speed and user control.

This research has been conducted at W!Games (Amsterdam, The Netherlands). The documents found below may be downloaded freely. The terrain editor application itself is property of W!Games and has not been released publicly.