Corona Slicer Material - C4D

In addition to the below content, see also: Corona Slicer Material at the Chaos Documentation Portal

With the Corona Slicer Material, you can use any object in your scene to cut away parts of another object where they intersect. This is a render-time effect so it will not change the actual geometry.

You can slice through all of your scene objects, or only through some of them.

This is how the original objects look in the viewport.

In this case, we are placing half of a cylinder with a Corona Slicer Material applied to it to cut away every object that is intersecting with it, allowing us to see the inner parts of the original model.

This is the resulting image after cutting through all the original objects using the Corona Slicer Material applied to the half of a cylinder. 

Where to find it?

You can create a Corona Slicer Material by any of the following methods:

A. Open the Corona menu located in the Material Editor and choose the Slicer Material:

B. Open the Node Material Editor, then Right-click  > New material > Slicer Material: 

Corona Slicer Material Parameters

Using the Corona Slicer Material

After applying a Corona Slicer Material to an object (we can refer to it as the "slicer geometry"), you can place it so that it intersects with other objects in your scene. The intersecting parts will be sliced off. 

Note: when using the inverse slicing option, only the intersecting parts will be rendered and the rest will be sliced off.

Steps:

1. Create any geometry and make sure it is intersecting with one or more objects in your scene; we will call this the "slicer geometry". 

2. Create a Corona Slicer Material and assign it to the slicer geometry. 

3. Now, at render time, the parts of the objects that are intersecting with the slicer geometry will be sliced off and only the remaining parts will be rendered. 

Corona Slicer Material examples

Example A

Here we will be using the Corona Slicer Material to slice off a part of a teapot.

General Scene description:

The scene contains a simple teapot and a stretched cube, and they were placed intersecting with each other. The Corona Slicer Material is assigned to the stretched cube: 

Example A - Expected result

In this case, the teapot will be sliced and the resulting geometry will remain OPEN until you turn on the "Enable" checkbox for the "Caps" section in the Corona Slicer Material:

Example A - Render:

Example A - Material Setup:

Example B - Expected result

In this case, the teapot is sliced, and the color of the "slicer geometry" is used for the caps: 

Example B - Render: 

Example B - Material Setup: 

Note: For this example, please consider that you should turn on the "Display color" option and define a color for the slicing geometry, otherwise, the default gray color will be applied.

Example C - Expected result

In this case, the teapot object is sliced, and the surface is using the material defined in the Corona Slicer "Material" section: 

Example C - Render: 

Example C - Material Setup: 

Example D - Expected result

In this case, by disabling the "Use cap material" checkbox, the teapot will be sliced, and the material of the teapot will be used for the capped surface: 

Example D - Render: 

Example D - Material Setup:

Example E - Expected result

So far you may have noticed that as the Corona Slicer material cuts away object parts, the lighting then enters the inner parts of the objects. There might be some cases where you want to keep the shadows without letting any extra light in, like for example in architectural visualization.

To achieve this result, let's do the following:

• Apply a Corona Ray Switcher Material to the slicer geometry
• Create a Corona Slicer Material and connect it to the "Directly visible" input section of the Corona Ray Switcher Material 
• Enable the "Caps" option for the Slicer material, and disable the "Cap material" option.

Now the objects will be sliced off, the material of the original objects will be assigned to the capped surface, and the interior lighting and shadows will remain as if the objects weren't sliced.

Example E - Scene Setup: 

Example E - Render: 

Example E - Material Setup: 

Example F - Expected result

In this example, the slicing geometry is using a Corona Slicer Material but this time the edges of the caps are rounded because of using the Corona Round Edges shader for both the Base material and the Caps material.

Example F - Scene Setup: 

Example F - Material Setup: 

Example G - Expected result

In this example, we want to show you that the Corona Slicer material can be also used to cut out Corona Proxies, objects used in Chaos Scatter, and objects used by Mograph Cloner.

Example G - Scene Setup: 

Additional Examples

Example H - Scene setup

In this example we are applying a golden metallic material to the slicer caps to give the scene a more stylized look.

Example H - Render: 

Example H - Material Setup: 

Example I

In this example we are are showing the difference between the "Inverse slicing" option toggled on and off.

Original geometry	Sliced geometry Inverse slicing is OFF	Sliced geometry Inverse slicing is ON

Troubleshooting

1. Using Corona Light Material in the slicer material may lead to black appearance on caps

Solution: use a material with self-illumination enabled instead. 
See: Should I use Corona Light material or Self Illumination to illuminate my scene?

 

Example:

Material Setup:

The viewport shows the geometry.	The material setup.

2. The displacement in the material included in the slicer material will be ignored. 

Solution: do not use displacement in the cap material as it is currently unsupported. Use bump instead, or nothing at all.

See also:

• Corona Slicer Material Issues and Solutions
• Corona Slicer Material at the Chaos Documentation Portal