NewtonLockToXY

[Overhertz]

hi there,,

i have been told there will be a tutorial for using newton with 2d (but i've read it comes with a performance loss)
i'd love to see a NewtonLockToXY(PNewtonBody) - which would lock a specific body to XY physical simulation, this would be good for making Newton for both 3d and 2d physics.

-Colin

[Julio Jerez]

There are several way of making a 2d engine out of a 3d engine, Some do not requeired changes, and other do.
Some are slower and others are faster believe it or not.

The one that is traditionally used with newton users is using a 2d joint, however that one makes the simulation slower since it forces each body in the simulation to have a 3dof joint.
One that is trivial is using a transformation that nullify the third coordinated but is is not very reliable,
The third one which makes the engine twice as fact, is to make the changes to the solver to make trully work in 2d.

When I get to the totorial, I will experimenet with all three and if the the 2D solver option is best I will do that, basically it will be a funtion like
NewtonWorldSet2dPlane (vector planeEquastion)

[Overhertz]

any news of those tutorials? or much prefered the function i sugested, however i have been thinking around a similar function that would be much better for all 2d and 3d coders, i wrote a 3d engine for simulations, however in some cases, some things in the 3d world need to stick to a certain axis, so rather than a NewtonLockToXY it would be super fantastic to see a NewtonLockAxis([X,Y,Z]);

so for example if there is a clock in a 3d world that needs to run in realtime, but also with destruction or damage properties, ie, nocking the hands out of place, the hands could be locked to their axis, but if the glass/plastic cover was broken completely, they could be unlocked and then they could fall in any direction. if you get my drift

i have seen some games also using 2d characters with 3d environments. anyways i hope to see some function like this.

-OHz

[JernejL]

You could write a 2D slider joint for this.

[Overhertz]

maybe true, but a simulation with many objects, needs to use as little resources as possible.