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Vanilla 1.1.9 is a product of Lussumo. More Information: Documentation, Community Support.

    So, I was once making a game and I set the density of a shape to 0 (assuming it would make the whole brothers group static). Instead, that shape actually MOVED!
    I ran some tests and zero-density shapes when glued behave like a limit of positive, low-density shapes. Watch:

    Then I tried an anti-ball (negative density):

    Didn't seem to work. Trying again editing the source:

    Whoa... That's weird. When I touched the negative ball to the bomb, it glitched up. WEIRD.

    Ok, let's do negative restitution:

    I think this has been done before, but not with a car...

    Next up: Zero-length springs.

    Doesn't seem too unusual even if one of the bombs hits the chain.-----------------
    3.14159265358979323846264338327950288... Nothing Here
    So apparently springs are more powerful long-range than distance joints are.
    3.14159265358979323846264338327950288... Nothing Here
    • CommentAuthorXyuzhg (Moderator)
    • CommentTimeApr 12th 2015
    A couple of brief comments/possible conclusions based on observations on the above tests:

    - Density 0 shapes are not actually physics-less. Alone they are set to 'static' merely because if anything were to hit the shape, it would move infinitely fast (in real physics, at the speed of light).
    - When these shapes are glued to something, physics works theoretically properly. Gravity (classically) does not accelerate a massless object, and you can likely demonstrate the correct physics by calculating the theoretical torque of the impact depending on the distance of the massless object from the central glued object.
    - Distance joints seem likely to function not as springs, which provide a force proportional to the stretched length, but as fixed-impulse joints that act directly against the direction the joint is compressed or stretched.

    Considering that the editor is open source now (on Github), you could look into the code yourself.-----------------
    Hopefully PA is inconsistent.
    If it's too much for you, Xyuzhg, then it's probably too much for me. :P-----------------
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