Image centered on cube material

Question

I'm trying to center a picture on the material of a cube and I'm able to get this using the window vector output.

The problem is that when I'm moving trough the 3d view it move the image position.

When I resize area it also resize the image.

I'm trying to find a way to show a centered image that rotate with the view, centered on the object and if i move trough the 3dview or if i resize the area it don't affect the image position/scale.

I'm trying to solve this directly on the material, no camera tracking since it’s not related with the window view and it require to be on camera mode wich is not the thing im looking for.

Answer 1

There are a couple of different ways to do this. I'll show you a technique combining object coordinates with constraints:

Notice the empty's constraints. It acquires the position and rotation of the camera, then uses a pair of locked track constraints to point its -Z axis at the designated object. (Track-to would work instead, but only when parented to the camera, with no inverse or transform; locked tracks are easier than that.) This empty is then used to generate object space coordinates for an image that will always "face" the camera, will always be the same size on the object, and will always rotate with the camera. I've moved the sphere to the periphery of the camera's view and rolled the camera to demonstrate this.

Alternate techniques would be to "billboard" the sphere or to use a UV project modifier, either of which should be searchable for more info.