Sub RGB2HSV(Byref hue As Integer,Byref sat As Integer,Byref value As Integer, Byval myrgb As Integer)
           Dim As Integer max=0,min=255,r,g,b
           r=(myRGB Shr 16) And &hff
           g=(myRGB Shr 8) And &hff
           b=myRGB And &hff
           If r>max Then max=r
           If r<min Then min=r
           If g>max Then max=g
           If g<min Then min=g
           If b>max Then max=b
           If b<min Then min=b
           value=max
           '? max, min,Hex(myrgb),r,g,b
           If max=0 Or max=min Then sat=0:hue=0:Exit Sub
           sat=255*(1.-(min/max))
           If max=r  Then
              hue=60.*(g-b)/(max-min)+IIf(g>=b,0,360)
           Elseif max=g Then
              hue=60.*(b-r)/(max-min)+120           
           Else
             hue=60.*(r-g)/(max-min)+240
           End If   
End Sub
Function HSV2RGB(Byval hue As Integer, Byval sat As Integer,Byval value As Integer )As Integer
 'hue 0 TO 359   0=red,  120 green   240 blue
 'sat is saturation  0 to 255  0 is neutral grey 255 is full color
 'value 0 To 255 is the brightness  0 is black 255 is maximum brightness
  If sat = 0 Then Return RGB(value,value,value)
     
  hue  Mod= 360
  Dim As Single h1= hue/60         
  Dim As Integer i = Int(h1)
  Dim As Single f = frac(h1)                 
  Dim As Integer p = value * ( 255 - sat )/256
  Dim As Integer q = value * ( 255 -  f*sat)/256
  Dim As Integer t = value * ( 255 - ( 1. - f )*sat)/256

  Select Case As Const i
    Case 0: Return RGB(value,t,p)
    Case 1: Return RGB(q,value,p)
    Case 2: Return RGB(p,value,t)
    Case 3: Return RGB(p,q,value)
    Case 4: Return RGB(t,p,value)
    Case 5: Return RGB(value,p,q)
  End Select
End Function

Screenres 800,600,32
ScreenLock
'increasing value
For J As Integer =0 To 255
For I As Integer =0 To 359
 Pset (J,i),HSV2RGB(I,255,J)
Next
Next

'decreasing saturation
For J As Integer =0 To 255
For I As Integer =0 To 359
 Pset (J+256,i),HSV2RGB(I,255-J,255)
Next
Next
'one hue ,saturation and value gradient
For J As Integer =0 To 255
For I As Integer =0 To 255
 Pset (i,j+360),HSV2RGB(0,i,j)       
 Pset (i+256,j+360),HSV2RGB(120,i,j)
  Pset (i+512,j+360),HSV2RGB(240,i,j)
Next
Next

'value gradient for saturation 0
For J As Integer =0 To 255
For I As Integer =0 To 255
 Pset (I+512,J),HSV2RGB(0,0,j)
Next
Next

Dim As Integer h,s,v
RGB2hsv(h,s,v,HSV2rgb(27,224,25))
Print h,s,v


SCREENUNLOCK
Sleep
 

Const div256 As Single =1.0/256.0
Function HSV2RGB(Byval hue As Integer, Byval sat As Integer,Byval value As Integer )As Integer
 'hue 0 TO 359   0=red,  120 green   240 blue
 'sat is saturation  0 to 255  0 is neutral grey 255 is full color 
 'value 0 To 255 is the brightness  0 is black 255 is maximum brightness
  If sat = 0 Then Return RGB(value,value,value)
     
  hue  Mod= 360
  Dim As Single h1= hue/60         
  Dim As Integer i = Int(h1)
  Dim As Single f = frac(h1)                 
  Dim As Integer p = value * ( 255 - sat )*div256
  Dim As Integer q = value * ( 255 -  f*sat)*div256
  Dim As Integer t = value * ( 255 - ( 1. - f )*sat)*div256

  Select Case As Const i
    Case 0: Return RGB(value,t,p)
    Case 1: Return RGB(q,value,p)
    Case 2: Return RGB(p,value,t)
    Case 3: Return RGB(p,q,value)
    Case 4: Return RGB(t,p,value)
    Case 5: Return RGB(value,p,q)
  End Select
End Function