3d - z rotation question!

programming flash
1

i’ve been working with Senocular’s tutorial for 3D scripting :
http://www.kirupa.com/developer/actionscript/faces_depths.htm

//great work, by the way
I made a drag function for it :)… My question is how to change the code
to actualy rotate on the z axis of the cube …
In his tutorial the cube rotates around the z axis of the stage no matter how other axis are rotated.
I think the part of the code that needs to be changed in order to simulate a more realistic rotation on z axis is :
// perform the rotations around each axis
// rotation around x
xy = cxy - sxz;
xz = sxy + cxz;
// rotation around y
yz = cyxz - syx;
yx = syxz + cyx;
// rotation around z
zx = czyx - szxy;
zy = szyx + czxy;
but i never been very good with trigonometry ! and I AM a newbe!:crazy:
Can anyone help me with this please!:esmirk: [SIZE=2][/SIZE][SIZE=2][SIZE=3][/SIZE][/SIZE]

2

rotation around z-axis:

That’s assuming that the z-axis isn’t rotated, the ideas discussed here take into acount the rotation of the axis
http://www.kirupa.com/developer/actionscript/trig_multiple_axis.htm

The code you posted also takes into account the rotation of the z-axis, excpet in those movies the z-axis is never rotated - add this code to the onEnterFrame function to rotate the z-axis with the up/down arrow keys:

cubeAxisRotations.z += (Key.isDown(Key.UP) - Key.isDown(Key.DOWN)) * 0.1;
3

thanks but that does not help me! … already dit it … what i need is to rotate the z axis with the cube … in the tutorial the z axis is alwasy normal to the stage … my question is how to rotate the z axis ?

4

thanks but that does not help me! … already dit it … what i need is to rotate the z axis with the cube … in the tutorial the z axis is alwasy normal to the stage … my question is how to rotate the z axis
(my fault …wasn’t very clear in the first place!)

by the way : this is a nice place to lose some time http://ghost.aesthetic.ru/index.htm

so can you help me with this…?:pleased:

5

can someone PLEASE help… i tried the kirupa tutorial but i just don’t have enough trigonometry knowledge to this:

the code is something like this: (part of it…
x = points*.x;
y = points*.y;
z = points*.z;

    // perform the rotations around each axis
    // rotation around x
    xy = cx*y - sx*z;
    xz = sx*y + cx*z;
    // rotation around y
    yz = cy*xz - sy*x;
    yx = sy*xz + cy*x;
    // rotation around z
    zx = cz*yx - sz*xy;
    zy = sz*yx + cz*xy;

    // now determine perspective scaling factor
    // yz was the last calculated z value so its the
    // final value for z depth
    scaleRatio = focalLength/(focalLength + yz);
    // assign the new x, y and z
    x = zx*scaleRatio;
    y = zy*scaleRatio;
    // create transformed 2D point with the calculated values
    // adding it to the array holding all 2D points
    TransformedPointsArray* = make3DPoint(x, y, z);
}

but the z axis is ALWAYS perpendicular to the stage… i would realy apreciate if someone could help me ajust the code so that the z axis spins with the cube, because in some point i need to roate around the z axis

PLEASE… PLEASE HELP

6

I’m bumping into the same problem. What have you tried already?
I spend at least one day on this problem. No luck so far.

7

as far as I can see you don’t want then to rotate cube (you want to rotate AXIS) so basicly you want to rotate camera, not objects

8

Ok, but that means you have to move the camera too if you want to keep the camera focussed on the object.