How can I create an invisible wall that hides wathever is outside him?

The cube is only there as an example. I want to do an animation where cars dissappear as they drive out of the plane.


Why don’t you make it a visible wall that is the same color as the background? If it’s cycles you would need to use emission shader and light paths node to make it only visible to the camera so it does not emmit light to the scene. You can cover the front with planes as well.

For such a simple scene, make a plane with an Holdout shader, and place it where you want the cars to disappear. Then, in the ‘Film’ panel of the ‘Render’ tab, turn the ‘Transparent’ option on.
In the compositor, add your background color to the render.

edit: or use MartinZ’s method, which is almost the same.

You can also use transparent plane and Light paths node to hide stuff selectively if you need to make it more complex:
That’s a transparent shader with a black outline on the plane above and then the orange material is mixed with transparent as well if it’s rays are at transparency depth of 1.
I think you might be able to come up with some cool effects with this. It doesn’t need to be only transparent, could be another color or something else.

Hey, that is pretty cool. :smiley:

Why do it simply, when there are needlessly complex ways? Make the wall a dynamic paint brush, that paints the cars on a paint map that is then used as a mask for a mix shader with transparency.

Thank you all! I finally did it with the Holdout shader; didn’t know about it. I took notes on the other methods too.


Your point is true. :smiley: I should clarify that I am not suggesting to do it with transparency and light paths, but I am just talking about some cool functionality that this topic brings to mind that could maybe inspire some ideas.

Oh, I wasn’t knocking your method, I was just being an idiot. There are virtues to all the different ways, it also depends on how/where the car disappears.

Oh, no no, you should have been knocking on my method :smiley: I opened up a new file and pretty much thought to myself: “OK, well now… how would one make this unnecessarily ridiculously complex… and what could come out of that?..” You caught me on that one :D. For some reason I imagined the cars being uniform color around and only becoming colorful in the focused area and I thought it could be done having a shader with color ramp assigning random colors per object with object info node and then that could be mixed with uniform color and separated by a transparent plane over the focus area… :smiley:

Ohh mann… I think OP has his head spinning right now!!! :spin: :spin: :spin: :spin:


Well :smiley: but who are you to judge me? :smiley: You have made my head spin many times in the past yourself! :wink:

I think you could also create a shader where the transparency is based on the position. Would need to have some sort of method to go from 0 to 1 instead of a smooth fade out.

you could also animate the object and move it out of the way or anim alpha value scale it to 0
and it is gone!

many ways to do it

happy cl

Or you could just keyframe the render camera in the outliner when you want the object to disappear if it is just a one or two frame jump.

I think only planes and node witchcraft can provide the nice appear and disappear from volume effect though:

I am not sure if this matters.


I use Refraction BSDF with IOR orf 1 to make the stuff behind the first plane become transmission rays so that the parts visible through themselves in the transparent shader that hides the object do not become visible before going behind the plane… If that makes any sense :smiley:

And now for something completly different: How about just use a boolean modifier? No more nodes witchcraft there!! :smiley: