Abstract: A method for rendering hair particles includes determining a grid with vertices and voxels bounding the hair particles, determining hair densities for the vertices, smoothing the hair densities, solving a distance function to form a distance field in response to the smooth hair densities, wherein a distance function returns zero at a pre-determined hair particle density, determining a surface normal direction for a hair particle in response to the distance field values, determining a hair illumination value in response to a first illumination source, and determining a shading value for the hair particle using the hair illumination value and the surface normal direction for the hair particle.

Abstract: A volumetric representation of a hair simulation model determines collective hair attributes. To determine inter-hair collisions, vertices include average velocities of the adjacent portions of the model. The average velocities determine target velocities. Forces for the model are determined from the target velocity values. To direct hair to a desired pose, vertices include target and current density values representing the density of adjacent portions of the model in the desired pose and current position, respectively. The differences in density values determine pressure forces applied to the model. To determine the illumination of the hair, vertices include density values representing the density of adjacent portions of the model. The density values define a hair surface, and signed distance values relative to the surface are determined for the vertices. Normal vectors are determined from the gradients of the signed distance values at locations corresponding the positions of the hairs.

Abstract: A volumetric representation of a hair simulation model determines collective hair attributes. To determine inter-hair collisions, vertices include average velocities of the adjacent portions of the model. The average velocities determine target velocities. Forces for the model are determined from the target velocity values. To direct hair to a desired pose, vertices include target and current density values representing the density of adjacent portions of the model in the desired pose and current position, respectively. The differences in density values determine pressure forces applied to the model. To determine the illumination of the hair, vertices include density values representing the density of adjacent portions of the model. The density values define a hair surface, and signed distance values relative to the surface are determined for the vertices. Normal vectors are determined from the gradients of the signed distance values at locations corresponding the positions of the hairs.

Abstract: A method for rendering hair particles includes determining a grid with vertices and voxels bounding the hair particles, determining hair densities for the vertices, smoothing the hair densities, solving a distance function to form a distance field in response to the smooth hair densities, wherein a distance function returns zero at a pre-determined hair particle density, determining a surface normal direction for a hair particle in response to the distance field values, determining a hair illumination value in response to a first illumination source, and determining a shading value for the hair particle using the hair illumination value and the surface normal direction for the hair particle.