Option Explicit

Private Sub cStart_Click()
  Dim rl As Long, gl As Long, bl As Long
  Dim rr As Long, gr As Long, br As Long
  Dim rz As Long, gz As Long, bz As Long
  Dim rk As Long, gk As Long, bk As Long
  Dim m As Long, i As Long, j As Long
  Dim r As Long, g As Long, b As Long

  cStart.Enabled = False

  m = 255

  rl = Abs(Val(tRed(0).Text)) Mod 256
  gl = Abs(Val(tGreen(0).Text)) Mod 256
  bl = Abs(Val(tBlue(0).Text)) Mod 256

  rr = Abs(Val(tRed(1).Text)) Mod 256
  gr = Abs(Val(tGreen(1).Text)) Mod 256
  br = Abs(Val(tBlue(1).Text)) Mod 256

  rz = Abs(Val(tRed(2).Text)) Mod 256
  gz = Abs(Val(tGreen(2).Text)) Mod 256
  bz = Abs(Val(tBlue(2).Text)) Mod 256

  rk = Abs(Val(tRed(3).Text)) Mod 256
  gk = Abs(Val(tGreen(3).Text)) Mod 256
  bk = Abs(Val(tBlue(3).Text)) Mod 256

  For i = 0 To m
    For j = 0 To m
      r = ((rl * (m - i) / m) + (rr * i / m)) * (m - j) / _
          m + ((rz * (m - i) / m) + (rk * i / m)) * j / m
      g = ((gl * (m - i) / m) + (gr * i / m)) * (m - j) / _
          m + ((gz * (m - i) / m) + (gk * i / m)) * j / m
      b = ((bl * (m - i) / m) + (br * i / m)) * (m - j) / _
          m + ((bz * (m - i) / m) + (bk * i / m)) * j / m
      pic.PSet (i, j), RGB(r, g, b)
    Next
    cStart.Caption = Str(i + 1) & "/255 ": cStart.Refresh
  Next

  cStart.Caption = "&Starten"
  cStart.Enabled = True
End Sub