The emission map is what is used to create the engine heating glow effect as the engine runs hot from being used for an extended period of time.

The best method I found in Photoshop is to use a gradient map, set to a fiery gradient like below that transitions from pure black to a dull red to a bright orange:

• Pure black at 0% position
• Dull red #680000 at 25% position
• Mid orange #d53700 at 50% position
• Warm orange #ff9800 at 100% position

Underneath, I have a greyscale image I use to actually map the brightness of the heat radiation. White is then mapped to that orange colour and duller greys lean towards the red.

For a Restockalike/Nertealike look, the inside of the engine cone should get brighter towards the combustion chamber. The exterior should stay within reddish colours.

The name of the exported emission texture should match the _Emissive name defined in the mu shader properties in Blender. The animation for the heating effect emission will be defined in the config file.