基于GPU的屏幕空间镜头水滴实时渲染

为了实时模拟真实性高的镜头水滴，提出一种在可编程图形硬件中实现的镜头水滴渲染新方法。首先三维场景被渲染到一张场景纹理，然后在GPU着色器中为镜头水滴产生不规则边缘接触曲线，使用该曲线快速构建水滴的曲面，最后采用曲面的表面信息并根据水滴的光学属性渲染出水滴的折射效果。采用该方法，可以实时地在屏幕上渲染出镜头水滴效果。使用GPU着色器进行渲染，可以在渲染出效果逼真的水滴的情况下，获得实时的帧率。采用光线折射物理方法渲染出的水滴的效果比直接使用纹理贴图方式获得的水滴的效果更逼真。

Real-time Rendering of Screen-space Water Drops for Camera Lens Based on GPU

One new approach was proposed to simulate realistic water drops on lens in real time using the programmable graphics hard-ware. First,the three-dimensional scene was rendered to a scene texture. Then the irregular edge curves of water drops on the screen were produced in the GPU shader. Surfaces of water drops were constructed quickly by using the curves. Lastly the refraction effect of water drops was rendered by using the information of the surface based on the optical properties of droplets. By using this method,can render the lens effect of water droplets on the screen with real-time. Using the GPU shader for rendering,can obtain real-time frame rate under the condition of rendering the realistic water droplets. The droplets effect rendered by light refraction physical methods is more realistic than by texture mapping methods.