近似软影下的三维增强绘制

3D enhancement rendering with approximate soft shadow

针对目前的三维增强绘制方法尚未涉及阴影效果这一现象,提出一种新的包含近似软影效果的三维增强绘制算法。针对简单光照场景,设计了一种新的尺度函数,应用该尺度函数调整每个像素的光亮度值,使得物体的表面细节看上去更加凸显;在此基础上引入近似软阴影效果,利用GPU的几何着色器提取物体的轮廓边生成近似半影区,通过调整半影区的衰减参数来控制半影区的大小和亮度,可以使软阴影变得更黑更集中。实验表明应用该方法可以得到整个三维场景一致增强的效果。

Considering that 3D enhancement rendering algorithms has not involved shadow so far, a new algorithm on enhancing models with approximate soft shadow is proposed. A new scaling method is designed for simple illumination scene, and lighting value of each pixel is modified using this method, so that details on surfaces are more prominent. Then the approximate soft shadow is introduced in that silhouette edges are extracted using the GPU＇ s geometry shader and then extended to generate penumbra area. The radiance intensi- ty and shape of the penumbra area is altered by adjusting the attenuation parameter, making the approximate soft shadow darker and smaller. The method is validated to be efficient as the whole scene is enhanced consistently.