Outdoor-sunlight-based method for realizing real-time dynamic shadow

Abstract

Disclosed in the invention is an outdoor-sunlight-based method for realizing real-time dynamic shadow. According to the method, a world coordinate of a pixel is converted into coordinate conversion of a sunlight space and a new position of a pix of a shadow graph in the sunlight space is obtained. When an object in a scene is drawn at second time, the depth of a relative light source and the depth of the shadow graph are compared pixel by pixel; when the depth is larger than the depth of the shadow graph, the pixel is determined to be in the shadow and corresponding shadow mixing is carried out; otherwise, the pixel is determined to be visual under light. Therefore, the shadow algorithm is mapped to a graph processing unit for execution, thereby accelerating drawing of the real-time shadow in a complex three-dimensional scene and improving the drawing efficiency. The vivid visual effect is realized and the scene reality is enhanced; and the drawing speed is also guaranteed.

Description

technical field [0001] The invention relates to the technical field of real-time dynamic shadows, in particular to a method for realizing real-time dynamic shadows based on outdoor sunlight. Background technique [0002] The development of modern graphics processing unit (Graphic Processing Unit, GPU) technology has greatly promoted the application of computer real-time rendering technology, and being able to produce shadows closer to reality has always been a very challenging task in the field of video games. Shadows are areas of darkness created by opaque objects blocking light. Those surfaces that cannot be seen by the light source will be in shadow, and those that can be seen by the light source will be outside the shadow. The boundary of the shadow can help people understand the appearance of the object As well as the relative position of objects, shadows play a vital role in 3D games, increasing the three-dimensionality and layering of images, and improving the degree ...

AI Technical Summary

Problems solved by technology

However, the current methods for implementing shadows in games are relatively low in speed and efficiency. When drawing in the game, all object models in the scene are traversed first, and each object model has a bounding box, which is within the visible range of the camera. The model in the model is traversed, the scene is drawn based on the parallel light source as the viewpoint, the depth information of the model relative to the light source is drawn into a shadow map (that is, the depth map), and then the calculated shadow map is used to draw the scene. The shadow map drawn is always perpendicular to the direction of the light source

The program generates this shadow map in each frame, connects the pixels before a certain frame and the pixels projected into the shadow of this frame, and obtains a tetrahedron, and the surrounding bounding box formed by this tetrahedron is the largest, resulting in sampling around Depth map is rough, low precision

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