The glow map can be used to define where your material will emit light. It doesn’t actually create a light source; it will just make your material shine. The glow map uses a standard texture where black will not emit light and all the other colors will. By clicking on the “More” button under the “Glow” control, you can import your own glow map.
Two other settings
Day& Night cycle is on the list of “Glow” settings. When this option is activated, the PBR material will only begin to glow when the sun goes down. During the daytime, only the diffuse map of the material will be displayed.
The same option can be found for light sources to illuminate your architectural project at sunset.
Weather option defines whether or not your PBR material will be affected by seasons and weather in the Twinmotion eco-system. When the weather option is deactivated, the material will not have water droplet or snow effect.
NOTE: absent this texture shine feature.
that we need so much!