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Per Ericson Ch. 9.5, after GJK detects intersection, EPA (Expanding Polytope Algorithm) is used for which next step?
ACompute penetration depth + normal
BUpdate the broad-phase AABB tree with new bounds
CCull contacts older than one frame from the buffer
DResolve the impulse via Coulomb friction model
Answer & Solution
Correct answer: A. Compute penetration depth + normal
Ericson Ch. 9: EPA grows the simplex outward in the Minkowski sum, ending at the closest face to origin from outside; that gives separating normal + depth.
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