Spirit of Half-Life (SoHL) is a modified game engine for Half-Life 1 modders that includes many new things not seen in the original Half-Life engine by Valve. This includes reflections, mirrors better lighting, weather like moving clouds, rain, snow, and fog. Physics capabilities like picking up objects and dropping them, or when some thing explodes objects go flying off in the direction.
Compiled binary of Spirit of Half-Life 1.9 (2011) by Unkle Mike, intended for mappers.
Source code for Spirit of Half-Life 1.9 (2011) by Unkle Mike
If anyone wants it,here you go.Codiac modified the SoHL 1.0 code and made the SoHL 1.2.