Generating textured polygon strip hair from strand-based hair for a virtual character

A system comprising:

• non-transitory computer storage configured to store:
• strand-based hair data for rendering hair of a virtual avatar, the strand-based hair data comprising strands indicative of shapes of strands of hair and a hair mask region indicative of a region on a head of an avatar where hair is to be generated;
• and
• a library of hair textures, each of the hair textures comprising an image of a hair style, each of the hair textures associated with hair texture properties;
• and
• a hardware processor in communication with the non-transitory computer storage, the hardware process programmed to:
• sample the strand-based hair data to obtain a first set of strands in the hair mask region;
• determine, from the strand-based hair data, a hairline or a part line;
• sample the strand-based hair data to obtain a second set of strands in a region near the hairline or in a region near the part line;
• generate a set of polygon strips (poly strips), wherein each poly strip is based on a strand in the first set of strands or the second set of strands, each poly strip comprising at least one polygon, and each poly strip associated with poly strip properties;
• match hair textures from the library of hair textures with the set of poly strips to obtain a set of matched hair textures, wherein a matched hair texture is usable to provide texture to at least one poly strip from the set of poly strips, and wherein the matching is based on a matching criterion between a poly strip property and a hair texture property;
• pack the set of matched hair textures into a texture space data structure representing a region of texture space;
• and
• output the texture space data structure and the set of poly strips.