Partial shadow image-based high-quality soft shadow fast generation method

Abstract

The invention discloses a partial shadow image-based high-quality soft shadow fast generation method. The flow chart of the method comprises the following two parts: adaptive light source sampling and partial shadow image acceleration, wherein whether light source sampling points are further subdivided is judged by back projecting a generated partial shadow image on a camera viewpoint so as to perform the adaptive sampling on a light source and generate a shadow image which is enough to ensure high-quality shadow; and calculating a surface light source shadow image region corresponding to visible shadow pixels when the back projection of the shadow image is performed, and adjusting a projection matrix and a viewport generated by the shadow image so as to accelerate the shadow image. By the method, the high-quality shadow is ensured, and meanwhile, the rendering efficiency can be greatly improved; the method is particularly suitable for the scene with a larger number of invisible shadow parts. The method supports a dynamic surface light source, a dynamic deformable scene, does not need calculation, and has the advantages of easiness in implementation, lifelike effect, high rendering effect and the like.

Description

technical field [0001] The invention belongs to the technical field of high-quality soft shadows, and in particular relates to a method for generating soft shadows based on multiple shadow maps. Background technique [0002] In real nature, soft shadows can be seen in any scene. Many hard shadow generation methods have been widely used in games, animation and virtual reality systems. However, how to quickly generate high-quality soft shadows to enhance the realism of virtual scenes and make scenes more realistic is still a complex task. high research value. In recent years, people have proposed many methods for soft shadow generation, mainly focusing on the improvement and extension of the Shadow Maps algorithm and Shadow Volumes algorithm. Because the physics-based soft shadow generation method requires a lot of visibility calculations, most of the current interactive applications use a method based on a single shadow map, and use a heuristic method to approximate the pen...

AI Technical Summary

Problems solved by technology

However, when the view point is close to the shadow, the area of ​​the penumbra area on the screen becomes larger, and the number of sampling points obtained by the algorithm easily reaches the maximum value, resulting in a sharp drop in efficiency.

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