Ever need to animate an object so it’s on top of your background and behind part of it at the same time? Wonder how to make a hand disappear into a cookie jar or how to show a scene unfolding as if you are viewing it through a pair of binoculars? Look no further and learn to use Clipping to solve all your hiding needs.

With Toon Boom Studio, forget about redrawing and piecing together your background and have the freedom to use bitmap images. Discover the properties of Clipping and use them to hide or reveal objects in your animation.

Preparing Your Layers

Creating a Clipping Mask for your animation is fairly simple.

In this example, we will show you how to hide part of the frog’s eyes if they pass beyond the perimeter of the eyeballs.

You can follow along with your own project, for this exercise you will need to place the following on different layers:

• The drawing object(s) to be clipped.
• The drawing object that the clipped object should be in front of for the most part.
• A cut-out shape of the section of your object where you would like the hidden object to be revealed (matte).

Creating and Ordering the Clipping Layer

1. Prepare the objects listed in the section above. Make sure that each object is on a different layer, including each eye, and that the matte is perfectly aligned with its corresponding drawing object.
2. In the Timeline view, click-on the plus button and from the dialog box, select Clipping from the layer type options.
3. Rename this layer and click-on the arrow beside the Clipping layer to show its sub-layer.
4. Select your matte layer, in this case the frog’s eyeballs highlighted by a red fill, and connect it to the Mask sub-layer. You will know if it has been successfully attached by its disappearance in the Camera view. Due to the fact that it is destined to be rendered invisible, the colour of the matte is of no consequence.
5. Connect the drawing object that you would like to be partially revealed as you animate it to the Clipping layer, in this case, it is both eyes. Your layers should look something like this:
   The frog layer remains unattached to the Clipping layer.
6. In the Camera view, test the mask by moving the drawing object(s) (eyes) behind the mask area, as well as beyond it. Marvel as they partially disappear beyond the edge of the Mask.

Using an Inverted Matte

Sometimes the area that you need to mask is quite large in comparison to the area that you wish to hide your object behind. Have no fear! The Clipping Mask can still be used. All you need to do is invert your matte shape area.

What You Will Need

In order to use the masking technique, you will need to place the following on separate layers:

• The drawing object(s) to be partially hidden.
• The background image or drawing object that the hidden object should be in front of for the most part.
• A cut-out shape of the section of your scene or object where you would like the hidden object to be revealed (matte).

Creating and Ordering the Clipping Effect Layer

Creating a Clipping layer for your animation is fairly simple.

1. Prepare the objects listed in the section above. Make sure that each object is on a different layer and that the mask drawing is overlaid and perfectly aligned with its corresponding drawing object.
   
2. In the Timeline view, click-on the plus button and from the dialog box, select Clipping from the layer type options.
3. Rename this layer and click-on the arrow beside the Clipping layer to reveal its sub-layer.
   
4. Select your matte layer, in this case it is the train tunnel highlighted by a green fill, and connect it to the Mask sub-layer. You will know if it has been successfully attached by its disappearance in the Camera view. Due to the fact that it is destined to be rendered invisible, the colour of the matte is of no consequence.
5. Connect the drawing object that you would like to be partially revealed as you animate it to the Clipping layer, in this case, it is the train. Your layers should look something like this:
   The train_tunnel_BG layer remains unattached to the Clipping layer.
6. In the Camera view, test the mask by moving the drawing object (train) behind the mask area, as well as beyond it. Marvel as it partially disappears beyond the edge of the Mask.