안녕하세요.
다름아니라 TImage를 회전하려고 찾다가 아래 소스를 발견했는데요..
pascal이라서 c++로 옮기려다 난해한 부분들이 있어서 질문 드립니다.

[1] 아래에서 예를들어
function GetColor32(bmp:TBitmap; x,y:integer):TRGBQuad;
var
  ps:PRGBQuad;
begin
  ps := bmp.Scanline[y];
  Inc(ps,x);
  Move(ps^,result,SizeOf(TRGBQuad));
end;

이게 return값이 뭔지, ps^에서 ^가 가리키는게 뭔지 등등... 잘 모르겠습니다 ㅠㅠ;;
C++이랑 비슷한 것 같으면서도 고치기가 많이 힘드네요.. ㅠㅠ

그리고
[2] 어떤 함수는 옆에 overload; 이렇게 되어 있는데 이것도 c++로 어떻게 바꿔야 하는지 등등
자세히 알려주시면 감사하겠습니다.. ㅠㅠ

ps. Graphic32는 이미지 위의 이미지가 투명 처리가 안되더군요... 게다가 저는 rotate를 90도, 180도, 270도 등 뿐만 아니라 특정 각도까지 구현해야 되는 상황인데, Graphic32에는 Rotate90, Rotate180, Rotate270밖에 없었습니다...

출처는 http://blog.livedoor.jp/junki560/archives/19004116.html 이구요
아래는 전체 소스코드 입니다...

unit Main;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure FormCreate(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
    procedure Button1Click(Sender: TObject);
  private
    { Private 宣言 }
  public
    srcbmp:TBitmap;
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

uses
  Jpeg;

function GetColor32(bmp:TBitmap; x,y:integer):TRGBQuad;
var
  ps:PRGBQuad;
begin
  ps := bmp.Scanline[y];
  Inc(ps,x);
  Move(ps^,result,SizeOf(TRGBQuad));
end;

procedure SetColor32(bmp:TBitmap; x,y:integer; color:TColor);overload;
var
  c:TRGBQuad;
  k:COLORREF;
  pd:PRGBQuad;
begin
  k := ColorToRGB(color);
  c.rgbBlue  := GetBValue(k);
  c.rgbGreen := GetGValue(k);
  c.rgbRed   := GetRValue(k);
  c.rgbReserved := 0;
  pd := bmp.Scanline[y];
  Inc(pd,x);
  Move(c,pd^,SizeOf(TRGBQuad));
end;

procedure SetColor32(bmp:TBitmap; x,y:integer;const rgbq:TRGBQuad);overload;
var
  pd:PRGBQuad;
begin
  pd := bmp.Scanline[y];
  Inc(pd,x);
  Move(rgbq,pd^,SizeOf(TRGBQuad));
end;

function GetBoundRect(const pts:array of TPoint):TRect;
var
  i,Xmax,Xmin,Ymax,Ymin:integer;
begin
  Xmax := pts[0].X; Xmin := pts[0].X;
  Ymax := pts[0].Y; Ymin := pts[0].Y;
  for i := 1 to High(pts) do
  begin
    if pts[i].X ＞ Xmax then Xmax := pts[i].X;
    if pts[i].X ＜ Xmin then Xmin := pts[i].X;
    if pts[i].Y ＞ Ymax then Ymax := pts[i].Y;
    if pts[i].Y ＜ Ymin then Ymin := pts[i].Y;
  end;
  result := Rect(Xmin,Ymin,Xmax,Ymax);
end;

function RotatePoint(const sn,cs:Double;Xc,Yc:integer;pt:TPoint):TPoint;overload;
begin
  result.X := Round(Xc+cs*(pt.X-Xc)-sn*(pt.Y-Yc));
  result.Y := Round(Yc+sn*(pt.X-Xc)+cs*(pt.Y-Yc));
end;

function RotatePoint(deg:Double;Xc,Yc:integer;pt:TPoint):TPoint;overload;
var
  sn,cs:Double;
begin
  sn := sin(pi*deg/180);
  cs := cos(pi*deg/180);

  result.X := Round(Xc+cs*(pt.X-Xc)-sn*(pt.Y-Yc));
  result.Y := Round(Yc+sn*(pt.X-Xc)+cs*(pt.Y-Yc));
end;

procedure OffsetPoints(var pt:array of TPoint;dx,dy:integer);
var
  i:integer;
begin
  for i := 0 to High(pt) do
    pt[i] := Point(pt[i].X+dx,pt[i].Y+dy)
end;

function PtInRct(const pt:TPoint; const r:TRect):Boolean;
begin
  result := (pt.X＞=r.Left) and (pt.X＜r.Right) and
            (pt.Y＞=r.Top) and (pt.Y＜r.Bottom);
end;

procedure RotatePoints(deg:Double ;var pts:array of TPoint);
var
  i,Xc,Yc:integer;
  r:TRect;
  sn,cs:Double;
begin
  r := GetBoundRect(pts);

  Xc := (r.Left+r.Right) div 2;
  Yc := (r.Top+r.Bottom) div 2;

  sn := sin(pi*deg/180);
  cs := cos(pi*deg/180);

  for i := 0 to High(pts) do
    pts[i] := RotatePoint(sn,cs,Xc,Yc,pts[i]);
end;

//--------------------------------------------------------

procedure RotateBMP32(deg:Double; src,dst:TBitmap; bkColor:TColor);
var
  srcR,dstR:TRect;
  pts:array[0..3] of TPoint;
  Xofs,Yofs,w,h:integer;
  ix,iy,Xc,Yc:integer;
  pt:TPoint;
  sn,cs:Double;
begin
  srcR := Rect(0,0,src.Width,src.Height);
  Xc := src.Width div 2;
  Yc := src.Height div 2;

  pts[0] := Point(0,0);
  pts[1] := Point(src.Width,0);
  pts[2] := Point(src.Width,src.Height);
  pts[3] := Point(0,src.Height);

  RotatePoints(deg,pts);
  dstR := GetBoundRect(pts);
  Xofs := -dstR.Left;
  Yofs := -dstR.Top;
  w := dstR.Right-dstR.Left;
  h := dstR.Bottom-dstR.Top;

  dst.PixelFormat := pf32bit;
  dst.Width := w;
  dst.Height := h;
  dst.Canvas.Brush.Color := bkColor;
  dst.Canvas.FillRect(Rect(0,0,w,h));

  sn := sin(pi*deg/180);
  cs := cos(pi*deg/180);

  for iy := dstR.Top to dstR.Bottom-1 do
    for ix := dstR.Left to dstR.Right-1 do
    begin
      pt := Point(ix,iy);
      pt := RotatePoint(-sn,cs,Xc,Yc,pt);
      if not PtInRct(pt,srcR) then continue;
      SetColor32(dst,ix+Xofs,iy+Yofs,GetColor32(src,pt.X,pt.Y));
    end;
end;

procedure TForm1.FormCreate(Sender: TObject);
var
  jpg:TJpegImage;
begin
  srcbmp := TBitmap.Create;
  jpg := TJpegImage.Create;
  try
    jpg.LoadFromFile(ExtractFilePath(ParamStr(0))+'Test.jpg');
    srcbmp.PixelFormat := pf32bit;
    srcbmp.Width := jpg.Width;
    srcbmp.Height := jpg.Height;
    srcbmp.Canvas.Draw(0,0,jpg);
  finally
    jpg.Free;
  end;
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
  srcbmp.Free;
end;

procedure TForm1.Button1Click(Sender: TObject);
var
  bmp:TBitmap;
begin
  bmp := TBitmap.Create;
  try
    Canvas.Draw(5,5,srcbmp);
    RotateBMP32(-35,srcbmp,bmp,clRed);
    bmp.TransparentColor := clRed;
    bmp.Transparent := true;
    Canvas.Draw(5,srcbmp.Height+10,bmp);
  finally
    bmp.Free;
  end;
end;

end.