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Today’s desktop rendering platforms typically use GPUs, which have become the most powerful computing chip to meet the growing visual needs, especially in ray tracing. However, ray tracing is challenging for mobile platforms because mobile GPUs need to accommodate insufficient computing power, hardware resources, and memory bandwidth. This paper presents a novel architecture for the mobile domain called Mobile Multiple stacks Ray Tracing (MMsRT). The most complicated calculations in ray tracing are completed through lightweight embedded design. MMsRT has three key features: First, we set multiple stacks to ensure multiple rays are parallel in the system. Second, it sets a stack cache to store the data in stacks when the storage space of multiple stacks is insufficient. Third, we adopt the data prefetching mechanism to set caches to improve the cache hit rate and performance. An accurate simulator test proves that our design can be applied to mobile devices. We calculate the performance of about 82.9 Million Rays Per Second (MRPS), the chip area is about 0.856mm², and 96.85MRPS/mm².

An n-vertex simple polygon P is said to have a Hamiltonian Triangulation if it has a triangulation whose dual graph contains a hamiltonian path. Such triangulations are useful in fast rendering engines in Computer Graphics. We give a new characterization of polygons with hamiltonian triangulations and use it to devise O(n log n)-time algorithms to recognize such polygons. We also give efficient algorithms for several related problems.

Water surface is an important element for rendering a realistic landscape image, particularly for visual environmental assessment. The incident light from the water surface to the viewpoint generally consists of two components, reflected and refracted light. The source of the latter is further subdivided into reflected light from the bottom of the water and scattered light in it. In order to render a realistic water surface, the calculation for each component of the light is a quite complex and time consuming task. We propose the fast rendering algorithms of the water surface for visual environmental assessment of outdoor scenes. The features are: (1) the reflected light from the water surface is rendered very quickly through the quasi-ray tracing techniques, which employ inversion and reflection mapping with consideration of the depth of objects mirrored on the water surface; (2) the refracted light coming through the water surface, which gives the color of water, is efficiently calculated by using a look-up table in which both characteristics of the light sources (both direct sunlight and skylight) and the effects of scattering and attenuation depending on turbidity are taken into account. In order to testify the proposed algorithms, some examples are given.

In this paper, we propose an approximate method for global illumination. We build an occluded estimator based on an algorithm of parallel line sweep for shadow maps. The virtual point lights are classified and a method is proposed to generate irradiance estimator (IE) by azimuthally analysis of normal. For each pixel rendering, we sample the IE around the pixel to fast approximate the percentage of irradiance to the point in the scene. The experiments demonstrate that our algorithm is an effective method of approximate global illumination.

While the radiosity method gradually established itself as a main rendering technique, there are still some fundamental problems regarding the radiosity method that remain unsolved. In this paper, we present a new radisosity approach for realistic image synthesis. Unlike the conventional radiosity method, the evaluation of light energy transfer is divided into two parts. In the first part, we establish the spatial light energy distribution of the source patch. In the second part, we subdivide the receiving surfaces accordingly and perform illumination calculation. The source patch and its receiving patches are related with each other through a global cube which acts as a light energy distributor. As no form—factors are involved, the conventional constraints on both the shooting patch and the receiving patch have been removed. Illumination coherence is exploited by performing dynamic subdivision of the receiving surface with respect to each current light source and by adaptive formation of the active light source. Accurate rendering of curved surfaces, anisotropic surfaces as well as the generation of high frequency details such as shadow edges, caustic borders and bump textures are supported efficiently. Experimental results show great potentials of the new approach.