How can I align an object in a discrete sense to the camera orientation?

Question

I don't want to move the camera to follow an object, but I would like to place an object using the currently selected camera.

The obvious use case is position text. 2D text could obviously be added in another tool (like Gimp). Other use cases could be aligning an object perpendicular to the camera (like a perspective gauge arrow).

Answer 1

The most obvious way is to align the object upon its creation. The option Align to View is present on all object creation operator's property, I use this mostly for text object. It will align the object's rotation to whatever active view perspective when the option is checked:

When that's not possible, sometimes I use a bit of Python, too, assigning the camera object's rotation_euler to the object to be aligned. From Python shell:

C.object.rotation_euler = C.scene.camera.rotation_euler

Answer 2

Another option is to use a Track To constraint to cause the text to always point a particular axis at the camera. Regular grs controls can be used to position it, and the Track To constraint will keep it oriented toward the camera, even if you have to re-position it.

Answer 3

Alternatively, you can set the camera as the object's parent if you're planning on animating your scene. Combine this with Adhi's answer to have it aligned. Select the text (or whatever), then the object (hold Shift), then CtrlP to set it as the parent.