for(size_t i=0; i<hair.size(); i++) {
hair[i].pos = hair[i].spawn_pt + hair[i].spawn_dir * hair_length;
-
- /* orthonormal basis */
- Vec3 vk = hair[i].spawn_dir;
- Vec3 vi = Vec3(1, 0, 0);
- if(fabs(vk.x > 0.99)) {
- vi = Vec3(0, -1, 0);
- }
- Vec3 vj = normalize(cross(vk, vi));
- vi = cross(vj, vk);
-
- /* identity when the hair points to the z axis */
- Mat4 basis = Mat4(vi, vj, vk);
-
- for(int j=0; j<3; j++) {
- float angle = (float)j / 3.0 * 2 * M_PI;
- /* dir of each anchor relative to hair root */
- Vec3 dir = Vec3(cos(angle), sin(angle), 0);
- dir = basis * dir;
- hair[i].anchor_dirs[j] = hair[i].pos + dir - hair[i].spawn_pt;
- }
}
return true;
}
/*
glColor3f(1, 1, 0);
glVertex3f(hair[i].pos.x, hair[i].pos.y, hair[i].pos.z);
- Vec3 end = hair[i].pos + dbg_force * 2.0;
- glVertex3f(end.x, end.y, end.z);
+ Vec3 fend = hair[i].pos + dbg_force * 2.0;
+ glVertex3f(fend.x, fend.y, fend.z);
*/
}
glEnd();