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Sparkling Effect in Virtual Reality Device

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Abstract

This paper discusses the method to display the surfaces that exhibit sparkling and depth effects. Sparkling effects are usually caused by the metallic flakes diffused in the paint or coating. The novelty of the approach is to explicitly model the sparkle normal vectors for rendering using an embedded device that allows us perceive depth effects in virtual reality like application. Light redirected by flakes to miscellaneous directions causes random twinkling particle effect. Since, each eye perceives light from different direction, there are two distinct perceived images with random particles for each eye. This effect causes the particles to be perceived within certain depth. We have created an application which allows us to render sparkling effect with arbitrary distributions of sparkles.

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Procedural texturing is a well known method to synthesize details onto virtual surfaces directly during rendering. But the creation of such textures is often a long and painstaking task. This paper introduces a new noise function, called multiple kernels noise. It is characterized by an arbitrary energy distribution in spectral domain. Multiple kernels noise is obtained by adaptively decomposing a user-defined power spectral density (PSD) into rectangular regions. These are then associated to kernel functions used to compute noise values by sparse convolution. We show how multiple kernels noise (1) increases the variety of noisy procedural textures that can be modeled and (2) helps creating structured procedural textures by automatic extraction of noise characteristics from user-supplied samples.