unit SColorPicker;

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}

interface

uses
 {$IFDEF FPC}
 LCLIntf, LCLType, LMessages,
 {$ELSE}
 Windows, Messages,
 {$ENDIF}
 SysUtils, Classes, Controls, Graphics, Forms,
 RGBHSVUtils, mbTrackBarPicker, HTMLColors, Scanlines;

type
 TSColorPicker = class(TmbTrackBarPicker)
 private
  FVal, FHue, FSat: integer;
  function ArrowPosFromSat(s: integer): integer;
  function SatFromArrowPos(p: integer): integer;
  function GetSelectedColor: TColor;
  procedure SetSelectedColor(c: TColor);
  procedure SetHue(h: integer);
  procedure SetSat(s: integer);
  procedure SetValue(v: integer);
 protected
  procedure Execute(tbaAction: integer); override;
  function GetArrowPos: integer; override;
  function GetGradientColor(AValue: Integer): TColor; override;
  function GetSelectedValue: integer; override;
 public
  constructor Create(AOwner: TComponent); override;
 published
  property Hue: integer read FHue write SetHue default 0;
  property Saturation: integer read FSat write SetSat default 255;
  property Value: integer read FVal write SetValue default 255;
  property SelectedColor: TColor read GetSelectedColor write SetSelectedColor default clRed;
 end;

procedure Register;

implementation

{$IFDEF FPC}
  {$R SColorPicker.dcr}
{$ENDIF}

procedure Register;
begin
 RegisterComponents('mbColor Lib', [TSColorPicker]);
end;

{ TSColorPicker }

constructor TSColorPicker.Create(AOwner: TComponent);
begin
  inherited;
  FGradientWidth := 256;
  FGradientHeight := 12;
  Width := 267;
  Height := 22;
  FHue := 0;
  FVal := 255;
  FArrowPos := ArrowPosFromSat(0);
  FChange := false;
  SetSat(255);
  HintFormat := 'Saturation: %value';
  FManual := false;
  FChange := true;
end;

(*
procedure TSColorPicker.CreateSGradient;
var
 i,j: integer;
 row: pRGBQuadArray;
begin
 if FSBmp = nil then
  begin
   FSBmp := TBitmap.Create;
   FSBmp.PixelFormat := pf32bit;
  end;
 if Layout = lyHorizontal then
  begin
   FSBmp.width := 255;
   FSBmp.height := 12;
   for i := 0 to 254 do
    for j := 0 to 11 do
     begin
      row := FSBmp.Scanline[j];
      if not WebSafe then
       row[i] := RGBToRGBQuad(HSVtoColor(FHue, i, FVal))
//       FSBmp.Canvas.Pixels[i, j] := HSVtoColor(FHue, i, FVal)
      else
       row[i] := RGBToRGBQuad(GetWebSafe(HSVtoColor(FHue, i, FVal)));
//       FSBmp.Canvas.Pixels[i, j] := GetWebSafe(HSVtoColor(FHue, i, FVal));
     end;
  end
 else
  begin
   FSBmp.width := 12;
   FSBmp.height := 255;
   for i := 0 to 254 do
    begin
     row := FSBmp.Scanline[i];
     for j := 0 to 11 do
      if not WebSafe then
       row[j] := RGBToRGBQuad(HSVtoColor(FHue, 255-i, FVal))
//       FSBmp.Canvas.Pixels[j, i] := HSVtoColor(FHue, 255-i, FVal)
      else
       row[j] := RGBToRGBQuad(GetWebSafe(HSVtoColor(FHue, 255-i, FVal)));
//       FSBmp.Canvas.Pixels[j, i] := GetWebSafe(HSVtoColor(FHue, 255-i, FVal));
    end;
  end;
end;
 *)

function TSColorPicker.GetGradientColor(AValue: Integer): TColor;
begin
  Result := HSVtoColor(FHue, AValue, FVal);
end;

procedure TSColorPicker.SetValue(v: integer);
begin
  if v < 0 then v := 0;
  if v > 255 then v := 255;
  if FVal <> v then
  begin
    FVal := v;
    FManual := false;
    CreateGradient;
    Invalidate;
    if FChange and Assigned(OnChange) then OnChange(Self);
  end;
end;

procedure TSColorPicker.SetHue(h: integer);
begin
  if h > 360 then h := 360;
  if h < 0 then h := 0;
  if FHue <> h then
  begin
    FHue := h;
    CreateGradient;
    FManual := false;
    Invalidate;
    if FChange and Assigned(OnChange) then OnChange(Self);
  end;
end;

procedure TSColorPicker.SetSat(s: integer);
begin
  if s > 255 then s := 255;
  if s < 0 then s := 0;
  if FSat <> s then
  begin
    FSat := s;
    FManual := false;
    FArrowPos := ArrowPosFromSat(s);
    Invalidate;
    if FChange and Assigned(OnChange) then OnChange(Self);
  end;
end;

function TSColorPicker.ArrowPosFromSat(s: integer): integer;
var
  a: integer;
begin
  if Layout = lyHorizontal then
  begin
    a := Round(((Width - 12)/255)*s);
    if a > Width - FLimit then a := Width - FLimit;
  end
  else
  begin
    s := 255 - s;
    a := Round(((Height - 12)/255)*s);
    if a > Height - FLimit then a := Height - FLimit;
  end;
  if a < 0 then a := 0;
  Result := a;
end;

function TSColorPicker.SatFromArrowPos(p: integer): integer;
var
  r: integer;
begin
  if Layout = lyHorizontal then
    r := Round(p/((Width - 12)/255))
  else
    r := Round(255 - p/((Height - 12)/255));
  if r < 0 then r := 0;
  if r > 255 then r := 255;
  Result := r;
end;

function TSColorPicker.GetSelectedColor: TColor;
begin
  if not WebSafe then
    Result := HSVtoColor(FHue, FSat, FVal)
  else
    Result := GetWebSafe(HSVtoColor(FHue, FSat, FVal));
end;

function TSColorPicker.GetSelectedValue: integer;
begin
  Result := FSat;
end;

procedure TSColorPicker.SetSelectedColor(c: TColor);
var
  h, s, v: integer;
begin
  if WebSafe then c := GetWebSafe(c);
  RGBToHSV(GetRValue(c), GetGValue(c), GetBValue(c), h, s, v);
  FChange := false;
  SetHue(h);
  SetSat(s);
  SetValue(v);
  FManual := false;
  FChange := true;
  if Assigned(OnChange) then OnChange(Self);
end;

function TSColorPicker.GetArrowPos: integer;
begin
  Result := ArrowPosFromSat(FSat);
end;

procedure TSColorPicker.Execute(tbaAction: integer);
begin
  case tbaAction of
    TBA_Resize:
      SetSat(FSat);
    TBA_MouseMove:
      FSat := SatFromArrowPos(FArrowPos);
    TBA_MouseDown:
      FSat := SatFromArrowPos(FArrowPos);
    TBA_MouseUp:
      FSat := SatFromArrowPos(FArrowPos);
    TBA_WheelUp:
      SetSat(FSat + Increment);
    TBA_WheelDown:
      SetSat(FSat - Increment);
    TBA_VKLeft:
      SetSat(FSat - Increment);
    TBA_VKCtrlLeft:
      SetSat(0);
    TBA_VKRight:
      SetSat(FSat + Increment);
    TBA_VKCtrlRight:
      SetSat(255);
    TBA_VKUp:
      SetSat(FSat + Increment);
    TBA_VKCtrlUp:
      SetSat(255);
    TBA_VKDown:
      SetSat(FSat - Increment);
    TBA_VKCtrlDown:
      SetSat(0);
    else
      inherited;
  end;
end;

end.