The methods for visualizing sampled spatial scientific data are known as volume rendering, where images are generated by computing 2D projections of 3D volume data. Since all the discrete data cells participate in the generation of each image, rendering time grows linearly with the resolution and complexity of the dataset. Empty cells in the data, which do not contribute to the final image, are of the important factors that increase the rendering time. During recent years, researchers have highly concentrated on improving the performance of these methods to achieve real time rendering. Skipping the empty space provides significant speedup and known as space leaping which requires implementation of special data structures and pre-processing. This paper presents a simple and efficient technique, that we name "ray-leaping," for the acceleration of total rendering process and eliminates the need for special data structures and pre-processing. (C) 2009 Elsevier Ireland Ltd. All rights reserved.