func writeOBJSurface(w io.Writer, surf *md3.Surface, posNorms, texCoords, triangles map[*md3.Surface]string) error {
fmt.Fprintf(w, "g %s\n", surf.Name())
n, err := io.WriteString(w, posNorms[surf])
if err != nil {
return err
} else if n < len(posNorms[surf]) {
return fmt.Errorf("Error writing positions and normals: only %d of %d bytes written")
}
n, err = io.WriteString(w, texCoords[surf])
if err != nil {
return err
} else if n < len(texCoords[surf]) {
return fmt.Errorf("Error writing texcoords: only %d of %d bytes written")
}
n, err = io.WriteString(w, triangles[surf])
if n < len(triangles[surf]) {
return fmt.Errorf("Error writing triangles: only %d of %d bytes written")
}
return err
}
