Note: the converter will only work if you have both Corona and the other renderer installed on the machine where you are using it. It is fine to use the trial or even expired trial license of the other renderer.
For example - if you are converting V-Ray materials to Corona, you need to have both Corona and V-Ray installed on your computer.
In addition to the below content, see also: Corona Converter at the Chaos Documentation Portal
Accessing the Corona Converter
The Corona Converter is installed by default with Corona and can be opened using:
- The dedicated Corona Toolbar icon:
- The quad menu after right-clicking in any viewport:
Note #1: In order for the Corona Converter to convert scenes created with other renderers and 3rd party plugins, those renderers and plugins must be installed in 3ds Max so that they are recognized and properly converted. You don't have to activate licenses for those renderers and plugins.
Note #2: If you are converting scenes from V-Ray to Corona, you need V-Ray version 3 or newer. Older versions are not supported.
Note #3: From Corona 12 onwards, the converter also supports converting 3ds Max Physical Materials to Corona Physical Materials.
The Corona Converter window.
Conversion Process
Corona Converter uses the Corona Physical Material as the conversion default. It is not possible to convert other materials to the Corona Legacy Material (previously called Corona Material), and any Corona Legacy Materials existing in the scene will be also converted to the Corona Physical Material.
Please note that while the converter was developed based on many user scenes and materials, and it generally tries to match the appearance of the converted materials as closely to the originals as possible, the conversion results may sometimes be imperfect. This means that when using the Corona Converter, you may need to make some minor manual adjustments to the converted materials. This is especially true in case of unphysical ("fake") materials and when setting up various material properties using extreme values. Some examples of incorrectly set up materials are presented in the "Examples" section below.
Once the conversion is finished, the Converter displays a MAXScript window informing about the statistics, such as how many materials were converter.
See also: Corona Physical Material
Normals Filtering in Corona 11
In Corona 11, we introduced a new option to change the normal filtering mode for all Corona Physical and Corona Skin materials in the scene.
This option is directly accessible within the Corona converter. You can switch between "None", "Linear", and "Roughness mod.", which allows you to balance texture quality and rendering speed based on your specific needs.
Learn more about this feature and its use case scenarios in our new bump/normal filtering article: New Bump/Normal filtering in Corona 11
Conversion Examples
Note: The incorrectly set up materials are for showcasing the possible conversion differences. When the material is using a physically correct setup, the conversion is should work as expected. When the material is using "fakes" and non-physical settings, the converted material may look different than the original.
Incorrectly set up material:
Refraction is used with Translucency, which is incorrect. The converted Corona Physical Material looks different than the original.
Before conversion:
After conversion:
Note: As you can see, the Corona Converter tries to keep all the information of the original material (Diffuse, Translucency, Reflection, and also their multiplications) in the newly created nodes, also naming them accordingly. This gives you a better view of the settings used and lets you modify them more easily.
Correctly set up materials:
Refraction is NOT used for a translucent material in this case (correct model for grass, leaves, paper etc.). The converted Corona Physical Material looks identical to the original material. Also note that the Thin shell (no inside) option is enabled for the Corona Physical Material, as "Enable Thin shell if translucent" option is checked in Corona Converter options.
Before conversion:
After conversion:
Note #1: Again, the Corona Converter kept all the settings in the nodes for better view and easy tweaking.
Note #2: There is no Reflection color parameter in the Corona Physical Material. Corona Physical Material's reflectivity is controlled with Base IOR or Specular (for non metals). For this, the original Corona Color for Reflection color is mixed with other parameters of Corona Legacy Material's reflectivity through Corona Mix and plugged into the Base IOR for Corona Physical Material.
Corona Legacy Material to Corona Physical Material:
Before conversion:
After conversion:
Before conversion:
After conversion:
3ds Max Physical Material to Corona Physical Material:
Example 1:
Before conversion:
After conversion:
Example 2:
Before conversion:
After conversion:
V-Ray Material to Corona Physical Material:
Example 1:
Before conversion:
After conversion:
Example 2:
Before conversion:
After conversion:
Example 3:
Before conversion:
After conversion:
Note: Corona Converter again tried to keep as many of the original settings as possible in newly created nodes. For Refractive, Translucent, and Volumetric materials sometimes there will be more nodes than in the original material. Nevertheless, the Converted materials will look and render just fine.
If you ever encounter a material that was converted incorrectly, please feel free to report it to us and we will do our best to improve our converter.