Android Question Box2D question?

[ilan]

hi

i am working on a new Box2D game. i want to create a revolutejoint to connect a wheel to a box
(creating a car) i know there is a WheelJoint but i would like to test it with a revolutejoint.

the question is, when i see some source and tutorials they use almost always Body.GetWorldCenter
in box2d (B4a) i cannot find GetWorldCenter i only have GetWorldPoint
do i need to set a vector with (0,0) and use GetWorldPoint?

    Dim v1 As lgMathVector2
    v1.Set(0,0)
    RevoluteJointDef.initialize(BodyA,BodyB,BodyA.getWorldPoint(v1))

(0,0 is the centre of my world)

 

[Informatix]

hi

i am working on a new Box2D game. i want to create a revolutejoint to connect a wheel to a box
(creating a car) i know there is a WheelJoint but i would like to test it with a revolutejoint.

the question is, when i see some source and tutorials they use almost always Body.GetWorldCenter
in box2d (B4a) i cannot find GetWorldCenter i only have GetWorldPoint
do i need to set a vector with (0,0) and use GetWorldPoint?

    Dim v1 As lgMathVector2
    v1.Set(0,0)
    RevoluteJointDef.initialize(BodyA,BodyB,BodyA.getWorldPoint(v1))

(0,0 is the centre of my world)

I don't remember the function name but there's one. I already used it.

EDIT: it's WorldCenter.

 

[ilan]

Thanx for your answer informatix

But there is no body.worldcenter
Only body.worldpoint

 

[Informatix]

Thanx for your answer informatix

But there is no body.worldcenter
Only body.worldpoint

Then you should open your eyes because there's one...

 

[ilan]

Btw i must say that box2d is awesome. I am studying it for 1 week and after you understand the logic it is not complicated at all.

I have created few examples with joints like a car and other examples and its going very well. I will start soon a very nice game so thank you very much for wrapping this lib.

Btw have you heard about Toxiclibs?
It is also a very good physic engine that also
Got 3d vectors. And it is simpler to use since you only handle the drawing part and all physics are done automaticly.

 

[ilan]

Then you should open your eyes because there's one...

Maybe i have an old libgdx version?

 

[Informatix]

Maybe i have an old libgdx version?

It seems to me that the property is there since the beginning.

 

[Informatix]

Toxiclibs?

Never heard of. There's a wrapper for B4A?

 

[ilan]

Never heard of. There's a wrapper for B4A?

have not found anything. this is something for a real expert

 

[ilan]

It seems to me that the property is there since the beginning.

you are right
it is the last option. i don't know why i have not seen it, maybe my eyes where really closed.

i thought it should start with Get... and i only saw GetWorldPoint and not ...center.

thank you

 

[Informatix]

you are right
it is the last option. i don't know why i have not seen it, maybe my eyes where really closed.

i thought it should start with Get... and i only saw GetWorldPoint and not ...center.

thank you

In B4A, all functions beginning with get or set with a single parameter are turned into properties without the prefix get/set.

 

[ilan]

In B4A, all functions beginning with get or set with a single parameter are turned into properties without the prefix get/set.

ok thank you

btw here is a link to some ToxicLibs examples: http://toxiclibs.org/2010/08/cfp-community-showreel-2010/