Sphere tracing and all that
نویسنده
چکیده
1 Distance Fields Given an implicit surface ∂S with S ⊆ R the corresponding distance field (also called signed distance function) D : R → R which maps a point p from the domain of the distance field R to a real-valued distance value is obtained by distance transforming the surface using the formula D(p) = sign(p) ·min{d(p, q) : q ∈ S} (1) The metric d(p, q) used is the standard Euclidean metric ‖p−q‖2. The expression sign(p) indicates whether p is an interior or exterior point of S.
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