Unity - The multiplatform game creation tools for everyone.
CareUEyes - CareUEyes is an eye protection software for windows that comes with blue light filter, screen dimmer, and break reminder
Godot Engine - Feature-packed 2D and 3D open source game engine.
f.lux - f. lux is a piece of software for Windows, Mac, Linux, iOS, and Android that provides a blue light filter over your screen. Research suggests limiting our exposure to blue light in the hours before bedtime can help us fall asleep faster.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Dimmer - A very small and free utility for Windows to reduce brightness on LCD/TFT screens.