Note: This guide requires the Rhino 9 WIP. This is a work in progress meaning that it is meant for testing and should not be used for project critical production work. The Rhino 9 WIP is available to anyone that owns Rhino 8.
This guide covers new Rhino Render material components to both create, edit and save materials within Grasshopper. This allows for mass editing and creation of materials used for rendering.
The Render material components are in the Rhino Toolbar > Materials section:
Basic Material Creation
The simplest of definitions to use Render material in Grasshopper and visualize the results in Rhino. We will build on this definition thru the rest of this guide as it allows us to monitor all the changes we are making.
Note: A Material exists in Grasshopper only until it is pushed into Rhino using the Content Cache Component.
Edit Existing Material
Existing materials can be edited by inputting a material component, inputting the material to the component.
In this case an existing Material is input to the left material component. This is an Apple Gloss Paint which is a generally green color (Red = 160, Green=207, Blue=103). Passing that material to the right material component and adding a red color swatch to the base color, the resulting Base Color is more red (Red = 232, Green = 16, Blue = 16).
Anatomy of a Material in Grasshopper
Here are a couple quick examples of what makes up most materials.
The Physically Based Rendering (PBR) material is the most flexible and potentially the most complicated. When first dropped on the canvas, it looks quite compact:
Use the down arrow at the bottom of the component to expand it fully to see all possible inputs into a PBR material:
A couple notes about the inputs and outputs:
- Most Color Channels can also take a texture. In the case above, a Grid texture is created and pushed into the Base Color channel.
- Other strengths such as Metallic and Roughness are a 0.00 - 1.00 value.
- Outputs for the material may be a value, or a complete texture as seen in the Base Color example above. Use a Render Preview component to interrogate the output for the type and the values.
Exporting Materials
Exporting material files (.RMTL) can be done with an Export Material Component:
The component can embed all required bitmaps and textures within the RMTL file using the Embed Input.
Also, the Overwrite input must be set to TRUE if the file needs to be updated multiple times.
Importing Materials
Materials can be imported directly from a file into Grasshopper by using the Import Material component. Directly imported materials will not have a associated GUID number associated with them, as there is not a corresponding material to reference in Rhino.
Alternatively, a Material can be imported from Rhino using the Query Material Component. Because these materials are imported from Rhino, they have an associated GUID number with them.
