Texturing

Hair Cards vs Strand Hair

Two ways to make hair in real time

Also known as: Hair cards · Strand-based hair · Hair grooms · Unreal groom · Hair cards vs strands · Real-time hair

Definition

Hair cards and strand-based hair are the two ways to build hair for real-time characters. Hair cards are flat, textured polygon strips that look like clumps of hair, and are cheap and widely used in games. Strand-based hair, called grooms in Unreal Engine, renders thousands of individual curves with proper lighting and shadows, giving a more realistic look at a much higher cost. Many projects use cards for the in-game version and strands for cinematics or high-end hardware.

In production

Choose by platform and budget: cards for consoles, mobile and VR, and strands for high-end PC and close-ups. Grooms can be authored in Blender, Maya or Houdini and imported, and some pipelines generate cards from a groom. Both need careful shading and a good silhouette, and the alpha and sorting of cards need a sensible setup to avoid problems.