Moving the center of rotation of a 3D object

[bogari0171]

I am trying to move the “Center of Rotation” of a 3D object (eg a cube) both horizontally and/or vertically.

Unfortunately I do not succeed. I get a displacement of the object, (instead of the center of rotation) and a frame where the center of rotation should be placed.

The object rotates always on its center, regardless of the displacement of the rotation point.

Does the function not work for 3D objects, or am I doing something wrong?

Additional comment: a cube can be set up in many different ways. Is there a specific solution better than all the others?

Thanks for help

Saluti

Claudio

[Lin Evans]

Hi Claudio,

A "Cube" is actually a construct of six objects rather than a single object so the easiest way to control the rotation center is to make the cube a child of a frame and manipulate the center of the frame which will in-turn control the cube as if it were a single object.

This is essentially true of all 3D objects in PTE - they are constructs of separate 2D objects so use a controlling frame to manipulate 3D objects as if they were a single object. That's the beauty of the hierarchical parent/child relationships with PTE.

Best regards,

Lin

[bogari0171]

Thanks Lin

Your suggestion is what I already tried

Now I tried again with a frame and a single jpeg image and I got the same result (see attachement)

If I use a single object, without a frame, eg a jpeg image, it works properly.

Do you think I shoul disinstall PTE and the reinstall it again?

Saluti

Claudio

[bogari0171]

Thanks Lin

Your suggestion is what I already tried

Now I tried again with a frame and a single jpeg image and I got the same result (see attachement)

If I use a single object, without a frame, eg a jpeg image, it works properly.

Do you think I shoul disinstall PTE and the reinstall it again?

Saluti

Claudio

[Lin Evans]

Hi Claudio,

No, I think your PTE is fine - let me experiment a little and get back on this...

Best regards,

Lin

[bogari0171]

Thanks Lin, I hope you can help me to solve the problem

Saluti

Claudio

[Lin Evans]

Hi Claudio,

Initial experimentation reveals that the best way to rotate the 3D object is to use two frames making the second frame a child of the first. Next make the cube or jpg the object of the second frame then move the top level frame to the position you wish to rotate on and move the middle level frame back to the original position. After doing this, rotating the original top level frame will rotate the object off-center. You do not move the centers on any of the frames or the grandchild (original cube or other object).

I haven't worked out the math yet to give you precise positioning, but here is a little pte file with a single PNG file which I rotate off center via the parent frame.

http://www.lin-evans.org/pte8/rotate.zip

If I get some more time to play with it this weekend I'll try to work out the details for you..

Best regards,

Lin

[denisb]

Hi,

if you use the slide style cube (slide style, experimental, cube), add a frame as parent and you can move the center of this frame to change the center of rotation of the cube

Denis

[bogari0171]

Lin, I think I solved my problem.

My mistake was to set a cube as a child of a frame ; then move the cube, and finally try to move the rotation point back to the center of the image (using the mouse and the shift key).

The correct way seems to be the following:

OK set cube as child; then move the cube to the new position and finally rotate the frame whose rotation point is still correctly positioned in the center of the image.

Thanks again and thanks to Denis who also contributed to clarify my point

Saluti

Claudio

[bogari0171]

Lin,

I succeeded in realizing a circle of 9 cubes, each spaced of 40 degrees.

Now the problem I see is that I do not know how to properly set their order in such a way that they appear without overlapping.

In the annexed figure you see that cube 7, 8 and 9 are partially overlapped, and I do not know how to solve the problem. If I invert some order, the problem is moved away to other cubes.

Would it be necessary to split the slide in two parts, or are there other ways to solve the problem?

Thanks and saluti

Claudio

[davegee]

Claudio,

One possible solution:

Split your "circle of Cubes" into two halves.

One half coming toward the viewer.

The other half retreating away from the viewer.

If you had 8 cubes instead of nine you could then changes slides every 45 degrees of rotation of your "master" frame. For nine cubes = 40 degrees.

If you have a different image on each face of 8 cubes (48 images) each new slide would then have to have different images on all of the faces to make it appear continuous - quite a challenge, but you could create a Style to do the hard work. The movement in each slide would be exactly the same but the images would have to change.

If you intend to revolve each cube about its own centre then you have another challenge.

DG

[bogari0171]

Thanks Dave

I tried with different numbers of cubes, from 3 to 9, changing the degrees accordingly.

So the solution to avoid overlapping is to split in more then one slide

I am now working in revolving each of the cubes on its own axis

Saluti

Claudio

[davegee]

No Claudio,

The overlap on the right is different to the overlap on the left, so each half of the circle of cubes needs to have its own "order".

Split the circle in half and arrange the overlaps differently in each half.

THEN you start thinking about the change of slide e.g. every 40-45 degrees and when there is no overlap between the two halves in the front and rear.

DG

[bogari0171]

Thanks Dave,

I will try your suggestion and see if I get what I am trying to achieve: eg 9 cubes rotating on a circle , each one revolving on its own axis and no averlap!

Saluti

Claudio

[bogari0171]

Dave,

I succeeded in my target to have 9 cubes rotating on a circle, with the possibility of each one revolving on its own axis.

I split the original circle in 6 slides, each one covering 60 degrees of rotation, in order to cover a full circle of 360 degrees, without any overlap of the cubes.

I can not annex an exe file because the size (3,4 Mbytes) slightly exceeds the allowed limit of 3,14 Mega.

I annex 2 pictures showing the implementation.

For simplicity I have only put one cube rotating on its axis

Thanks again for your help

Saluti

Cladio

[davegee]

Hi Claudio,

Just for fun here is a Cube Style.

No images required.

Import the Style.

Just add a blank slide to a Project and highlight it. Apply the Cube Style from User Styles.

It will create 7 Slides.

Run in Preview and you can then analyse.

Cube Style.ptestyle

DG

[bogari0171]

Thanks Dave

I am well aware of this style to produce a cube.

In the 9 cubes of my circle I used another style, and sometimes I also use a third one.

It is still not clear to me if anyone of these three styles (or even others) is the best for normal use in PTE, or if the choice is irrelevant.

By the way do you have a template for a sphere or a cylinder?

Thanks again

Saluti

Claudio

[davegee]

Not yet.

DG

[Jean-Cyprien]

Hi Claudio,

What you want to do is not an easy problem.

If I understand you correctly, here is the solution.

In the O&A window you'll be able to understand how it is made.

http://www.picturestoexe.com/forums/index.php?/topic/18129-christmas-tree-of-24-cubes/

in english (thanks to Lin) :

http://www.picturestoexe.com/forums/index.php?/topic/18132-jean-cypriens-cube-christmas-tree-gift-sample/

And an example :

http://www.slideshowclub.com/files/file/259-my-2014-advent-calendar/

It is possible for each cube to revolve about its own center. See for exemple the two gondolas of the new mery-go-round here (which is exactly the same problem) :

http://www.slideshowclub.com/files/file/275-my-2014-christmas-present/

Best regards

Jean-Cyprien

[bogari0171]

Thanks Jean Cyprien

Actually I succeeded in doing what I wanted.

In the sense that I have been able to construct a circle of 9 cubes rotating around the center of the slide, and each one with the possibility to rotate on its own axis. Then I made all this as child of frames, so I can change any angle of view according to my whishes.

In order to achieve this, I made 6 slides, each one covering 60 degree of rotation, so I was able to avoid any overlap of the cubes, but I had to adjust the order of the cubes in each slide (OK, this is painful, but it works!)

I do not know if there is a simpler way to achieve this result.

I would like to show it, (so you could verify the correctness of the procedure) but I do not know how to do it. If I make an exe file of the project, I can not add it to my post, because the dimension of the file slightly exceeds the limit of 3,13 M, (actually3,45) imposed in the rules of the Forum.

Do you have any suggestion?

Thanks for help

Saluti

Claudio

PS. I am a fan of your slideshows and I am well aware of your superb realizations for Advent and Christmas, but I am still far away to achieve such results.

[Jean-Cyprien]

See my PM !

[bogari0171]

Sorry, malheureusement I do not understand PM (?)

Could you clarify what do you mean?

[Lin Evans]

Claudio,

Personal Message - look at the top right of your display and click on the number surrounded by red....

Best regards,

Lin

[bogari0171]

Thanks Lin,

I am now in contact with Jean Cyprien.

Back to my original point of my topic I think that the lesson I learned is that in order to move the center of rotation of a multiple object ( eg a solid figure) the normal way of "Shift+Mouse" may not be used.

The multiobject should be child of a frame and the center of the frame should be considered as the rotation center.

I think this discussion may be closed, and if necessary (in order to avoid mishandling of multiple objects) this difference could be recorded in the PTE online help under the "objects and animation"

Thanks again

Saluti

Claudio