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Here you can find more information on each component (the options are the same as in the Maxwell Standalone Material Editor; the purple icon):
The Override Map option is not available here as the plugin is handling it a bit differently than the Maxwell editor. You can use it directly from the Texture edition panel. Once you activate it, the projection parameters of the texture will be marked in blue and you’ll be editing the override parameters. Every texture that has the Override Map option active will be using the same parameters.
Additionally, in Rhino, it shows a box showing the custom alpha channels related to the material, letting you remove, add and edit them:
Layer. It lets you change the layer opacity, its mask and its blending mode.
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