click:     refresh

    a:         move mouse left/right 
    b: shift + move mouse left/right 
    c: ctrl  + move mouse left/right 
    d: alt   + move mouse left/right 

    color = rgba(a, b, c, d) with mapped domain
  

  
    a: -0.727493246554817
    b: 0.8472160181842638
    c: 0.11767143483319753
    d: 2.417075102691374