Small Question

[PaldxD]

Complex to say.
So I will graphically demonstrate the problem.


Why after I add as a child he "translates" there? and this is not where?

[EgonOlsen]

I don't get the problem...

[PaldxD]

http://img341.imageshack.us/i/problemtx.jpg/

I need to make when adding a child in another cube it does not translate to another corner.
how to explain ...
as in the photo, while adding another child of the cube as cube it rotates back ...


too complex to explain, but it is something simple

[Kaiidyn]

Could you post some code ? Might help to show the problem better..

[EgonOlsen]

Yes, some code might help, because i still understand the problem. Which cube in that picture is right or wrong or expected to be different? Which one is the child of which?

[PaldxD]

Let's go!

Code Select Expand

for (int i = 0 ; i<25;i++){
ball.rotateZ((float) ((2.0f / 25) * Math.PI));
cub = Primitives.getCube(1);
ball.addChild(cub);
}

"forming a flower"

[Nick]

It's still not clear what you want, but I can make some guesses what's going wrong.

You can probably use some of these functions for some objects when rotating and translating:
setRotationMatrix(new Matrix());
setTranslationMatrix(new Matrix());

Also did you mention that you didn't use the i variable in the for loop?

If you're still stuck, please post some more code or explain what you want to achieve.

[EgonOlsen]

Seems as if you somehow expect cub to get the current rotation from "ball" assigned at the moment where you add it as child, but that's not the case. Your code rotates ball 25 times and makes each cub a child of ball, so that each cub inherits the same rotation of 25*(2.0f/25). I'm not sure if the child/parent relations is really what you are after in this case.

[PaldxD]

This is fail!!!

but....



http://www.4shared.com/file/NW-FYi2e/try.html

check this.

[EgonOlsen]

When you add cube2 as a child of ball, it will do the same rotation as the ball. It's only natural that it changes its position according to the balls rotation. I'm still not really sure what exactly you want. The second slide looks like the first one to me except that the cube carries another number. Anyway, try something like

Code Select Expand


for (int i = 0 ; i<25;i++){
ball.rotateZ((float) ((2.0f / 25) * Math.PI));
        cub = Primitives.getCube(1);
cub.setRotationMatrix(ball.getRotationMatrix().cloneMatrix());
        cub.translate(?,?,?); // Position on top of ball, the same for each cub
        cub.setRotationPivot(<position of ball's transformed center-cub's transformed center>);
}


That's untested...it might not work but maybe it's a starting point. I don't think that a child relation between cub and ball is what you want here.

[PaldxD]

solution!   

Code Select Expand

for (float i = 0; i < 25; i++) {
ball.rotateZ((float) ((2.0f / 25) * Math.PI));
cube = Primitives.getCube(1);
cube.translate((float) (10 * Math.sin(i * (2f / 25f) * Math.PI)),
(float) (10 * Math.cos(i * (2f / 25f) * Math.PI)), 0);
cube.setRotationMatrix(ball.getRotationMatrix().cloneMatrix());
ball.addChild(cube);
world.addObject(cube);
}