三维数据域可视化体绘制中的色彩合成新方法

在科学视算的研究中，目前各种直接绘制三维数据域的方法，都是运用合成算子线性递推地合成各个象素的色彩。本文提出一种新方法，将色彩合成由线性递推的纵向合成变为二维面（虚拟面）上简单的分布合成。新方法在合成色彩时省去了线性递推方法中所需的乘法运算。更有意义的是，当此方法与三维数据域体绘制的投影成象方法结合时，利用已形成的虚拟面，可以方便地生成大小不同的可视图，而不必重复进行投影操作。本文同时证明了，在一定精度内，放大了的图象反映了在相应精度下具有插值效果的可视信息。

A NEW METHOD OF COMPOSITING COLORS IN VOLUME RENDERING

In present volume rendering algorithms,the color at a pixel on the image plane is composited by recursively using a compositing operator performing on the effects of samples along the project path.In this paper,a new compositing color method is proposed and implemented. By this method,the effects of all samples are distributed over a plane , referred to as the virtual plane,and compression is then conducted on the virtual plane to produce rendered images.The improved method takes away multiplications,which are necessary in all the current compositing color methods. When the new method is integrated with the projection approach for volume rendering, based on the virtual plane,the rendered images in various sizes can be produced without recalculation of projection.