This timelapse video is all about retopologizing the hair meshes in a way that they look and work well for both the viewport for animation and when subdivided.

Other helpful links:

• Rain - File 4: Retopology & UV mapping: The file that includes the original retopology of Rain.

General Links

• Short version of the creation of Rain
• Recap video of the creation of Snow
• Rain .blend files
• Snow .blend files
• Course Resources