REAL-TIME OUTDOOR RENDERING USING HYBRID SHADOW MAPS

In outdoor rendering, the sun's position, sky color, clouds, shadows, trees and grass are important factors to consider for effective realism. In this paper, three of these are combined. The sun's position is calculated based on specific longitude, latitude, date and time using Julian date; the sky color is created by Perez model and the shadows are generated using a technique called Hybrid Shadow Mapping (HSM). A new method is used to combine these important factors. Another contribution of this paper is a new algorithm to create shadows with higher quality and with higher frames per second when compared with other algorithms such as Layer Variance Shadow Maps and Cascade Shadow Maps. HSM has been tested to justify an increase in the quality and a decrease in the rendering time in a typical application. In this paper, real-time sky color and shadows, with effect of the sun's position are combined to create a realistic outdoor environment without worrying about components such as sky color and shadow position at different times of the day. Commercial games for outdoor rendering are possible beneficiaries of this technique. It could also be advantageous for teachers of physics who teach about earth orbit, and it could be applied in building and architectural designs.