Visibility and Hidden Surface Removal

Area subdivision
• Divide-and-conquer and spatial partitioning
in the projection plane. Idea:
– Projection plane is subdivided into areas
– If for an area it is easy to determine visibility,
display polygons in the area
– Otherwise subdivide further and apply decision
logic recursively
– Area coherence exploited: sufficiently small
area will be contained in at most a single visible
polygon
© Machiraju/Zhang/Möller
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