[ODE] Lots of stacked boxes/breaking constraints (was Re: Inside ODE)

[nlin@nlin.net]

> incidentally, this is why a stacked
> box wall works better if the boxes don't touch each other in the
> same row - if they did then the single box-box contact will
> sometimes be used for horizontally adjacent boxes and will not
> help keep the stack up.

I'm not sure I follow. Isn't collision detection done for each pair of
bodies? The above seems to imply that a horizontal box-box contact might
"use up" the single box-box contact and thus eliminate a second box-box
contact (with a different box).

In other words with the following three boxes

+---+ +---+
|   |1|   |
+---+ +---+
        2
      +---+
      |   |
      +---+
    
Contact "1" being registered might cause contact "2" not to be registered?
I would have thought that the contact between the two horizontal boxes would
be independent from the contact between the two vertical boxes.

-Norman