Abstract: With the development of scientific visualization and its application，volume rendering of irregular data sets is a hot now.Because of the disaccord of the size，shape，distributing of the dot in the irregular set，the authors have encountered many difficulties.There are mainly three kinds of direct volume rendering algorithm：ray-casting，cell projection and the fast volume rendering algorithm.This paper absorbs and learns from the methods above，makes use of the speciality of irregular data sets，takes some measures to accelerate redering.Experiments prove that this method achieves its effect.

Key words: volume rendering, projected tetrahedra, irregular data sets

摘要： 随着科学计算可视化的发展及其在实践中的应用，非规则数据场的可视化已成为当前的研究热点之一。由于非规则场中样点的大小、形状和分布是不一致的，在成像时面临更多的困难。常用的方法有光线投射法，单元投影法，以及单元投影与光线投射相结合等算法。吸取了上述算法的优点，同时利用非规则数据场的一些特性，采用了一些加速措施来加速绘制。通过实验验证，可以达到比较理想的效果。

关键词: 体绘制, 投影四面体, 非规则数据场