Ray CastingCompared to Forward Mapping, there are other ways to compute views of scenes defined by geometric primitives. One of the most common is ray-casting. Ray-casting searches along lines of sight, or rays, to determine the primitive that is visible along it.Properties of ray-casting:
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Usual Graphics Pipeline![]()
Ray Casting
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In a ray-casting renderer the following process takes
place.
1. For each "Screen-space" pixel compute the equation of the "Viewing-space"
ray.
2. For each object in the display-list compute the intersection of the given
ray
3. Find the closest intersection if there is one
4. Illuminate the point of intersection