2
$\begingroup$

One of the great mysteries to me is how Blender takes a 2D input of the mouse moving on the screen and calculates a 3D rotation or translation using that input. Oftentimes when I move something it looks correct from the angles that I am looking at it, but when I rotate the viewport it did something seemingly random in a axis that I couldn't see.

So how exactly does Blender evaluate my 2D input of my mouse into a 3D translation or rotation?

Improve this question
$\endgroup$
2
  • $\begingroup$ One axie is locked on default, you can unlock in setting. $\endgroup$
    – X Y
    Commented May 18, 2022 at 22:42
  • $\begingroup$ @XY I think your comment is a bit misunderstandable, "one axis" is very vague and could also make beginners tend to think it's one of the global axes, the world's X, Y or Z axis. But it's the depth axis of the active view in which you are translating (as Jachym's answer correctly explains). And if you hint on unlocking this axis, would you mind telling where to find that because it might not be obvious for everyone? $\endgroup$
    – Gordon Brinkmann
    Commented May 19, 2022 at 12:09

1 Answer 1

Reset to default
2
$\begingroup$

3D translation based on mouse input disregards depth.
So you cannot move the object further/closer to camera than it already is.

This is counter-intuitive to our brain, that's why objects may look placed correctly even when they're not.

No matter how hard i try, I can't move the ball further from camera enter image description here

Improve this answer
$\endgroup$
3
  • 1
    $\begingroup$ +1 It's generally the depth of the active view in which you are translating, not necessarily the camera's depth. $\endgroup$
    – Gordon Brinkmann
    Commented May 19, 2022 at 12:10
  • 1
    $\begingroup$ Additionally, since rotation is asked for as well: if you click R to rotate, the object is only rotating around the depth axis (the one going virtually "into" the viewport), if you double-tap R instead, the depth axis is locked and the object rotates around the vertical axis (moving left and right, shown with red cursor arrows) and the horizontal axis (moving up and down, shown with green cursor arrows). This double-tap option doesn't exist for moving with G. $\endgroup$
    – Gordon Brinkmann
    Commented May 19, 2022 at 12:20
  • 1
    $\begingroup$ So is moving it basically like using view orientation and locking the Z axis? $\endgroup$
    – tempdev nova
    Commented May 19, 2022 at 13:59

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .