Emissive Materials are materials that emit light on their own, without the need for an external light source.

In the lobby, I used emissive materials to make the windows on the buildings glow at night. I ended up using the same image in the base color and emissive outputs.

Emissive materials are extremely versatile. You can plug a simple color (vector3) into the emissive slot to create a uniform glow, or use an image to have a more complex pattern emit light. If the same image is connected to both the base color and emissive output, the base color determines what gets illuminated.

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Here is a valuable tip when creating emissive materials.

• Prioritize emissive surfaces over actual lights when possible. This can give your scene a vibrant, stylized look while keeping performance high.

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Again, I am still learning, this is just what has helped me. If anybody has any feedback, reply below.