HSV => RGB

function HSV2RGB(h: integer; s, v: double): GraphABC.Color;

  Hi: integer;

  f, p, q, t, r, g, b: double;

  Hi := (h div 60) mod 6;

  f := h / 60 - (h div 60);

  p := v * (1 - s);

  q := v * (1 - f * s);

  t := v * (1 - (1 - f) * s);

 

  case Hi of

    0: begin r := v; g := t; b := p; end;

    1: begin r := q; g := v; b := p; end;

    2: begin r := p; g := v; b := t; end;

    3: begin r := p; g := q; b := v; end;

    4: begin r := t; g := p; b := v; end;

    5: begin r := v; g := p; b := q; end;

  end;

 

  Result := GraphABC.RGB(round(r * 255), round(g * 255), round(b * 255));