In this paper a new direct volume-rendering method is presented for fast
display of iso-surfaces. In order to reduce the data to be processed, the
algorithm eliminates those voxels which are invisible from a specific domain
of viewing directions. The remaining surface points are stored in an appropriate
data structure optimized for fast shear-warp projection. The proposed data
structure also supports the application of cutting planes in order to visualize
the internal part of the volume as well. Unlike many other surface-oriented
techniques, the presented method does not require any specialized hardware
to achieve interactive frame rates, thus it can be widely used in
medical imaging applications even on low end hardware.