Update getBodiesUnsafe() to return a slice of size getMaxBodies()#25
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r0ckHopper wants to merge 3 commits into
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Update getBodiesUnsafe() to return a slice of size getMaxBodies()#25r0ckHopper wants to merge 3 commits into
r0ckHopper wants to merge 3 commits into
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getBodiesUnsafe() returned ptr[0..getNumBodies()] but its values can go upto 1024 (getMaxBodies) After destroying bodies, the active count shrinks but remaining bodies stay at the same slots, causing out-of-bounds exceptions. The underlying Jolt array also uses max_bodies, so slicing to getMaxBodies() is safe.
Same issue as addressed in commit 77a907d getBodiesMutUnsafe() returned ptr[0..getNumBodies()] but its values can go upto 1024 (getMaxBodies) After destroying bodies, the active count shrinks but remaining bodies stay at the same slots, causing out-of-bounds exceptions. The underlying Jolt array also uses max_bodies, so slicing to getMaxBodies() is safe.
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Currently getBodiesUnsafe() returns a slice of size getNumBodies() but getBodiesUnsafe() actually returns a pointer to slice of size max_bodies.
The issue comes when you delete bodies from the middle and try to access bodies of higher index
getBodiesUnsafe does not reorganize the elements before giving a slice so you can get an out of bounds error
example of the issue is:
let bodies be
[b0, b1, b2]
if you delete b1 jolt physics updates bodies to
[b0, invalid, b2]
but if you call getBodiesUnsafe you only get
[b0, invalid]
so if you do tryGetBody( all_bodies, b2) then it will look for b2 at index 2 which is out of bounds