EyeonTips:Script/Reference/Applications/Fuse/Classes/ChannelStyle

From VFXPedia

A ChannelStyle object stores properties like color, opacity and softness that tell Fusion how to turn an ImageChannel into an image. This way, you can reuse an image style for multiple calls to ImageChannel:PutToImage().

The color, gradient and softness options at the bottom of the shading tab of the Text+ tool basically expose the things you can do with a ChannelStyle. There are a few examples that demonstrate the usage of the ChannelStyle object: ShapeTest Fuse, Lines Fuse and the Flare Fuses.