Real-time Rendering of Detailed Height Fields Using Hardware-based Ray Tracing Acceleration

Abstract

The paper considers the task of real-time visualization of detailed height fields on the GPU. An efficient, two-stage technology for rendering procedural surface of height field, based on hardwareaccelerated tracing of primary rays, is proposed. The first stage, preprocessing, includes constructing an accelerating data structure - a 2D array of bounding boxes (AABB) covering height field surface. At the second stage, for each visualization frame, an image of height field is constructed on the ray tracing pipeline, involving ray generation, «ray-AABB» intersection detection and searching inside the AABB for the intersection of the ray with bilinear surface of height field. The paper describes key methods for creating a gapless AABB array and extracting AABB-candidates with closest to the viewer «ray-surface» intersections. Based on the created technology, a software complex in C++ using the Vulkan API and the GLSL shading language was developed. The complex was tested on a number of detailed height maps, including 10K? 4K map of the lunar impact crater Aristarchus. The results obtained confirmed high efficiency of the developed solution and the possibility of its application in virtual environment systems, simulators, scientific visualization systems, etc.