Is this basically what’s going on with clear rotation and apply rotation?
Clear rotation (alt+R) makes the axis of the object go back to 0,0,0 and it brings the object with it.
Apply rotation (ctrl+A) also makes the object axis go back to 0,0,0 but in this case the axis goes back but the object stays in place.
Is apply rotation just for convenience so future clear rotations will reposition our object back to where we did an apply rotation to it? Or is there some other use for apply rotation?
Thanks for any ideas regarding clear rotation and apply rotation and their intended purposes. I’m trying to get a sense of what they are used for generally.
I heard that some people, as soon as they add anything immediately do a clear rotation (or an apply rotation?)…for example I heard because bones sometimes need 0,0,0 rotation in order for certain tools to work on them.
Also, I’m not clear about why alt+R is actually clear scale and rotation and not just clear rotation.
Alt-R is Clear Rotation; Alt-S is Clear Scale. Both will clear any Transform and reset R and S (of the Object) to the state in which it would be had it been Added in Top View (Z-UP). Since it applies to the Object it also applies to the Object’s Axis and any Datablocks (Mesh, Curve Armature etc) linked to it.
Ctrl-A applies any Rotation (to 0.0.0) and Scale (to 1.00 for each coordinate) of the Object and its Linked Datablocks as they appear in the 3D Window and Resets the Axis to the state it would be had it been added in Top View. If you add an Object in Front View it is Y-UP; Ctrl-A on it and the Axis is changed to Z-UP but the Object and Mesh remain as they were.
Thanks for confirming that Fligh…and for adding more info like
“Ctrl-A applies any Rotation (to 0.0.0) and Scale (to 1.00 for each coordinate) of the Object and its Linked Datablocks as they appear in the 3D Window” …nice to know it works in any user view, because I for some reason was only testing these things in standard Top, Front, and Right views.
Also, still wondering what some of the common uses are for using apply rotation…and where we may need to be careful to use either clear rotation or apply rotation…like what’s the general concept behind them, and in what parts of the work process are they generally needed, etc.
Well, when using Constraints or some of the Deform Modifiers, where one Object uses another Object as a Target, they will only work as expected if the axii of both objects are alligned. Example; if you have a rigged Mesh Character it helps if both the Mash and the Armature are Z-Up and when you constrain that to a Path (FollowPath Constraint) it helps if the Curve, Mesh and Armature are all Z-Up and that the Armature (which will be the Object constrained to the Path Curve) has it’s X-Axis pointing in the same direction as the X-Axis the Curve Object lies along (note that you can change the Track (and in some cases the UP) axis in F7 but doing so will only (simply, merely) be relative to what the present state of the Axis is; it doesn’r set a new orientation… it’s relative).
All the above applies only to Ctrl-A. Alt-R/S/G just removes all prior translations back to the last Ctrl-A (even those set by adding an object in User View) and doesn’t reset (or recalculate) anything.
When you create “a cube” and move it around and scale it and whatever-else-you-do to it …
… at the end of the day, the computer is still thinking in terms of the original placement, size, and rotation of “the cube” … translated and scaled and rotated in whatever-way-necessary to get from “here” (the cube’s original placement…) to “there.”
Eventually, you might wish to say to the computer, “fuhgeddabout how this cube got here… [dammit…] it’s ‘here!’”
In other words, “whereever this cube is, right now, from this moment forward shall be[come] ‘rotation zero, scale zero, translation zero.’”
So… no matter how this particular cube managed to wind up “where it is, rotated the way that it is, and scaled the way that it is,” from this moment forward “this is its ‘starting point.’”
The apparent position, rotation, and scaling of the object does not move in the slightest, but from this moment forward all of these parameters are now “defined to be” zero.
Fligh thanks so much, that really helps me understand the difference between, and uses of, clearing and applying rotations. Very helpful examples you give.
And thanks also sundialsvc4, for the helpful way of thinking about apply rotation. That also helps.
If anybody has any thoughts about some possible variations of clear or apply rotations that may be specific to pose mode, I’d love to know about that too. For example, apply rotation in pose mode…should that even be an option…and what does that do? Because after apply rotation in pose mode, clear clear rotation goes back to original position…ie apply does not “stick” as it does in object mode. Just curious about that.
And why is there no apply or clear rotation in edit mode? But that may another thing altogether.
