@Name: Clifford
@Version: 1.0
@Description: Clifford attractor.
@Reference: http://paulbourke.net/fractals/clifford/
@A: -1.4
@B: 1.0
@C: 1.6
@D: 0.7
@E: 1.0
@F: 1.0
return vec3(
sin(@A*p.y) + @B * cos(@A*p.x),
sin(@C*p.z) + @D * cos(@C*p.y),
sin(@E*p.x) + @F * cos(@E*p.z));