Get Rotation of a Group or Object

conzar · 26th September 2006, 09:14 AM

Hot dang your right. Just saw your post today ... so I'll try that tonight.

Thanks

conzar · 26th September 2006, 08:54 PM

Humm. Seems like the above code rotates an object about the origin. How would I rotate it about the center of the object? I would like the same functionality as the rotate buttons on the left side bar.

Thanks.

Dennis · 26th September 2006, 09:38 PM

Quote:

Originally Posted by conzar

Humm. Seems like the above code rotates an object about the origin. How would I rotate it about the center of the object? I would like the same functionality as the rotate buttons on the left side bar.

You'll want to move the object to the origin, rotate it, then move it back to its original position. The rotation function exposed through the SDK doesn't handle the translation part of the equation.

Alternatively, you could call the code that AC3D uses when you use the left side bar rotate function. Check out the ac3d.tcl file in the "scripts" directory and look for "ac3d rotate_axis_angle". This snippet might help:

Code:

// Specify axis where 0 = x, 1 = y, 2 = z
int axis = 1;
float degrees = 90.0f;
tcl_command( "ac3d rotate_axis_angle %d %g", axis, degrees );

The above code should rotate the selected geometry 90 degrees around the Y axis, relative to the object/selection center. Note that this is off the cuff and untested.

Good luck

conzar · 27th September 2006, 01:56 PM

Yep. That did the trick.

Thanks!!!!

jmaida · 25th October 2006, 04:52 PM

I have examining the file format for rotation values. The description of the format says that there a field called "rot" followed by values of the rotation matrix. After rotating objects and groups of objects all over the place and saving the file at various steps of the process, I failed to find "rot" anywhere in the saved file. It appears that a rotation is applied to the vertices then simply forgotten. However, that does not seem to be the case for translations. This seems to me to be an odd inconsistancy and an omission of some useful information that is needed to restore the initial condition of object.

26th September 2006, 09:14 AM	#1
conzar Member Advanced member Join Date: May 2006 Posts: 36	Re: Get Rotation of a Group or Object Hot dang your right. Just saw your post today ... so I'll try that tonight. Thanks

26th September 2006, 08:54 PM	#2
conzar Member Advanced member Join Date: May 2006 Posts: 36	Re: Get Rotation of a Group or Object Humm. Seems like the above code rotates an object about the origin. How would I rotate it about the center of the object? I would like the same functionality as the rotate buttons on the left side bar. Thanks.

27th September 2006, 01:56 PM	#4
conzar Member Advanced member Join Date: May 2006 Posts: 36	Re: Get Rotation of a Group or Object Yep. That did the trick. Thanks!!!!

25th October 2006, 04:52 PM	#5
jmaida Junior Member Member Join Date: Sep 2005 Posts: 10	Re: Get Rotation of a Group or Object I have examining the file format for rotation values. The description of the format says that there a field called "rot" followed by values of the rotation matrix. After rotating objects and groups of objects all over the place and saving the file at various steps of the process, I failed to find "rot" anywhere in the saved file. It appears that a rotation is applied to the vertices then simply forgotten. However, that does not seem to be the case for translations. This seems to me to be an odd inconsistancy and an omission of some useful information that is needed to restore the initial condition of object.