Topic: How to apply a gravitational force to an object?

How to apply a gravitational force to an object? i want to make a sphere and the player walk 360 around it?

  • anael
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Re: How to apply a gravitational force to an object?

well, you can first set the gravity to zero with setGravity :
http://wiki.maratis3d.org/index.php?title=SetGravity

and then at each frame add a central force with a vector going from the object to the center of the sphere.
with addCentralForce : http://wiki.maratis3d.org/index.php?tit … ntralForce

Re: How to apply a gravitational force to an object?

This is what i have but cant get it to work.


-- get objects
player = getObject("player")
earth= getObject("earth")


-- scene update
function onSceneUpdate()

    gravity = {0, 0, 0}
    setGravity(gravity) -- set current scene gravity
   
    addCentralForce(earth, {0, 0, 0}, "local")
    end
   
end

  • anael
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Re: How to apply a gravitational force to an object?

you need a direction vector, in your code it's all zero.

-- get objects
player = getObject("player")
earth = getObject("earth")

setGravity({0, 0, 0}) -- set current scene gravity to zero

g = 0.98 -- your new hand made gravity force

-- scene update
function onSceneUpdate()
   
    vec = normalize(getPosition(earth) - getPosition(player)) * g
    addCentralForce(player, vec)
    
end
  • anael
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Re: How to apply a gravitational force to an object?

but be sure the origin of hearth and player are centered in the mesh

Re: How to apply a gravitational force to an object?

Thanks very much anael. this help me understand vectors better.

Re: How to apply a gravitational force to an object?

It still falls off the side of the earth tho? how do i make the gravity flip?

Re: How to apply a gravitational force to an object?

Heres the project:  https://drive.google.com/folderview?id= … sp=sharing

  • anael
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Re: How to apply a gravitational force to an object?

1 - name your objects : "earth" and "player"
2 - import the script in the scene :
http://wiki.maratis3d.org/index.php?tit … to_objects