ray casting
<graphics> A simplified form of ray tracing. A ray is fired from each
pixel in the view plane, and information is accumulated from all the voxels in
the volume data it intersects.
Each voxel is first given an associated colour and opacity. The ray is sampled
at a fixed number of evenly spaced locations and the colour and opacity are
trilinearly interpolated from the eight nearest voxels. These are then composed
linearly back to front to give a single colour for the pixel.
Ray casting was invented by John Carmack for the game Wolfenstein 3D. It is
faster and lower quality than ray tracing, and is ideal for interactive
applications. It parallelises well, although random access is needed to the
voxels.
(2004-01-06)
Nearby terms:
raw data « raw mode « RAWOOP-SNAP « ray casting
» Rayleigh distribution » Ray Tomlinson » ray
tracing
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