光线投射算法中重采样的设计和实现

体绘制技术在医学成像和科学可视化领域有着极为广泛的应用，但由于其巨大的计算开销，限制了其实时动态体绘制的应用，因此许多研究人员致力于静态体绘制加速算法的研究，为了提高体绘制速度。分析了三维规则数据场重采样的原理。光线投射算法中对3D数据场重采样的实现方法；根据具体重建对象，提出了在3D数据场重采样中采用球形包围盒的方法，给出了人体头部和眼球的三维可视化结果，实验表明：这种算法能有效地减少重采样的计算量，并使求交计算更加简单。

The Design & Implement of Resampling in Ray Casting Algorithm

Volume rendering has wide applications in some areas such as medical imaging and scientific visualization. But the algorithm of volume rendering can not be still put into use in practical medical imaging applications, simply because it could not meet the speed requirement for interactive operation due to the large amount computation involved. At present, many researchers are working hard to study the foundation of accelerating algorithms. In order to resolve the volume rendering speed problem in 3D visualization of medical image, this paper analyses the theory of the 3D Regular Data Set' resampling and introduces the way to realize it in details. Since the shapes of some object to be reconstructed are close to sphere, this paper presents a new data Set' resampling method, which adopts the round box depending on the object. The results of the 3D visualization, which are about the human heads and eyes, are given in this paper. The experiment result shows that method effectively reduces the calculating time, and at the same time makes the calculation of the point of intersection more simply.