added pitch rate for particles

src/Affection/Types.hs

@@ -132,6 +132,7 @@ data Particle = Particle
   , particlePosition  :: (Double, Double) -- ^ Position of particle on canvas
   , particleRotation  :: Double           -- ^ Particle rotation
   , particleVelocity  :: (Int, Int)       -- ^ particle velocity as vector of pixels per second
+  , particlePitchRate :: Double           -- ^ Rotational velocity of particle
   } deriving (Show, Eq)
 
 data ParticleSystem = ParticleSystem