Am 26.01.2013 23:11, schrieb Trevor G Quayle:
> clipka <ano### [at] anonymousorg> wrote:
>> Am 26.01.2013 15:43, schrieb Trevor G Quayle:
>>> clipka <ano### [at] anonymousorg> wrote:
>>
>>>> (0) [optional, just for speed] If the cubes' bounding boxes don't
>>>> intersect, the cubes don't intersect.
>>>>
>>>> (1) If any corner of the smaller cube is inside the larger cube, they
>>>> intersect. (No need to test the other way round.)
>>>>
>>>> (2) If any edge of the smaller cube intersects any surface of the larger
>>>> cube, they intersect. (Again no need to test the other way round.)
>>>>
>>>> (3) In any other case, they don't intersect.
>>>>
>>>>
>>>> Note that this only works for cubes, not for generic boxes.
>>>
>>> #2 is the key.  if #1 is true then #2 is true as well.
>>
>> Not necessarily: The smaller cube could be entirely contained in the
>> larger one.
>
> OK, you are right about that, didn't think of that.  The way to check that is to
> check for intersecting spheres based on the inner boundary (distance from cube
> center to face).

That's insufficient if the smaller cube is /very/ small and embedded in 
the larger cube close to one of its corners.

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