Corona for 3ds Max
Corona Select Material
This page provides information on the Corona Select Material.
Last updated 12 January 2026
This page provides information on the Corona Select Material.
Overview
The Corona Select Material lets you plug multiple materials into a single material editor node, and then choose which one of them to use in the actual rendering. To select a specific item, simply click the radio button next to that item's name.
See also: Corona Select Map

Properties
Material count – Specifies the number of materials that you wish to select between.
List of materials – Shows the names of all connected materials and allows selecting one of them.

MAXScript Access
As stated in the Corona Select Material UI when material count is higher than 25, more items can be accessed through MAXScript. Below is a simple guide with a few possible use cases:
In the Compact Material Editor:
Set number of items in the Corona Select Material in the 1st material editor slot to 100:
<code data-v-c2b1f83f=""><span data-v-c2b1f83f="" class="line">meditMaterials[1].mtlCount = 100</span></code>
Add a new Corona Material to the 1st slot of the Corona Select Material:
<code data-v-c2b1f83f=""><span data-v-c2b1f83f="" class="line">meditMaterials[1].materials[1] = CoronaMtl ()</span></code>
Select 5th item:
<code data-v-c2b1f83f=""><span data-v-c2b1f83f="" class="line">meditMaterials[1].selected = 5</span></code>
In the Slate Material Editor:
Set number of items in the specific Corona Select Material (in this case called "mymaterial") to 100:
<code data-v-c2b1f83f=""><span data-v-c2b1f83f="" class="line">rootScene[#SME][#View1][#mymaterial____CoronaSelectMtl].Properties.reference.mtlCount = 100</span></code>
Add a new Corona Material to the 1st slot of the specific Corona Select Material:
<code data-v-c2b1f83f=""><span data-v-c2b1f83f="" class="line">rootScene[#SME][#View1][#mymaterial____CoronaSelectMtl].Properties.reference.materials[1] = CoronaMtl ()</span></code>
Select 5th item of the specific Corona Select Material:
<code data-v-c2b1f83f=""><span data-v-c2b1f83f="" class="line">rootScene[#SME][#View1][#mymaterial____CoronaSelectMtl].Properties.reference.selected = 5</span></code>
Troubleshooting
There is something wrong with numbering when adding and selecting materials through MAXScript!
Due to a small bug in the current version of Corona, the indexes start from different numbers, so for example if you assign a material to slot 1 of the Corona Select Material it will actually be assigned to slot 0. So to select it you will need to use selected = 0, not selected = 1.
How do I know what commands I should use?
You can open the MAXScript Listener (Scripting > MAXScript Listener...) and enable the MacroRecorder (MacroRecorder > Enable) to record various actions you perform in the material editor (such as creating new materials, changing the number of items in the Select Material, plugging different materials into different slots, selecting specific materials, etc). This can help you find the syntax which you will need to use, specific to your scene.
Examples

Green Paint

Blue Paint

Orange Paint
Click here to see the material setup
