FA-87515 / Collision detection broadphase / Member archive

Positive collision groups cannot override masks · case 05

Ragdoll parts in the same positive group ignore each other when masks disagree.

Member previewVariant 5 · 3 implementations · 8 checks per implementation

Case contract

solve(fixtures, candidates): fixture [id, body, category bits, mask bits, group, sensor, body type]. A candidate [a,b] is accepted unless: same body; neither body is dynamic; both are sensors. Group rule: equal nonzero groups override masks (positive always collide, negative never); otherwise require (catA & maskB) and (catB & maskA). Return sorted unique [min,max] accepted pairs.

Why this case matters

Broadphase stages decide which object pairs ever reach narrowphase; a wrong boundary, ordering or bookkeeping rule silently drops real contacts or floods the solver with false candidates.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
case 1	`[[2, 4], [4, 9], [8, 9]]`	`[[2, 3], [2, 4], [3, 7], [4, 9], [8, 9]]`	Failed

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This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

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