The Cutaway material enables you to non-destructively subtract geometry from your model.
Setting up the Cutaway Material
Simply add the geometry you want to use for the cut, place it so it cuts into your model and assign the cutaway material to it.
You can import simple geometry (sphere, cube etc.) into your scene from the Main Menu, Edit, Add Geometry.
No Caps - The cuts will be left open.
Inherit Caps - The cuts will be capped with the material of the part that is cut into
Color - The cuts will be capped with a solid color. When this option is selected the cap color will be shown - click the color input to set another color.
Material - Use another material for the caps. Drag a material from the Library to the material field in the cutaway material properties. Click the material field to edit the material.
If you only want to cut into some of the parts of your model you can exclude objects from the cutaway. Click the add button and select the nodes you want to exclude. To remove a part from the exclusion select it in the list and click the delete button.
Opacity maps on cutaway caps are not supported
Fade Animations are not supported with cutaway materials
Show Caps is intended to be used together with fully closed surfaces (solids). Caps may show artifacts with non-closed geometry.
If you have two co-planar parts where one is excluded form the cutaway and you use inherit caps or material caps. Artefacts can occur on the surface of the excluded material.
Cutaway material may interfere with shadows on the environment ground. If the cutaway object touches the environment ground it will cut that just as it cuts into regular parts.
Workaround: Add a groundplane (Edit > Add Geometry > Add Ground Plane) and exclude it from the cutaway.
When the Camera is inside the cutaway object, Color caps do not show and when using Material caps, all objects in the scene will be displayed with the cap material.
Cutaway with Inherit caps used on transparent materials may produce artefacts. Following material types are affected:
Excluded objects have incorrect reflections - Objects excluded by cutaway show reflections of the inside of the object being cut.
Bad Shadows on excluded objects.
Basic Glass and Thin Film appear as metal when applied to an excluded cutaway object - Product mode only!
Wrong shading on Toon material when used for cutaway with inherit caps or as material caps. The cut will appear to have color caps instead of the desired Toon appearance. Possible workaround: Try to disable Material Contour in the Advanced settings of the Toon material.