impossible triangle

abstract angle angles appear art background blocks brain brains close cognitive color colored colors concept connect connected corner corners creative dark deception deceptive design dimension dimensional disappear exaggeration experiment eye eyes fun geometric geometry grid human illusion illusions illustration impossible lines logo loop misleading optic optical orthogonal overlap overlapping parallel penrose perceive perceived perceptual perspective perspectives physiological purple quickly seem shape side sides slanted spots system test tests the triangle tribar trick tricks twist vector violet visual visually white