В конце два варианте FrameBufferunit.

Та что без GL, GLu, GLext - пробовал, это реализация:
{= Получение контекста для вывода ф-ми OpenGL на экран ========}
function TForm1.GetScreenContext(const CanHandle: THandle): HGLRC;
var nPixelFormat: Integer;   PFD: TPixelFormatDescriptor;
begin          { См. Краснов, Ex25 - MDI, Глава 1 }
{................. Устанавливаем формат пикселей .....................}
FillChar(PFD, SizeOf(PFD), 0);
  With PFD do begin
  nSize := SizeOf(PFD);   nVersion := 1;
  dwFlags := pfd_Draw_to_Window or pfd_Generic_Accelerated or
    pfd_Support_OpenGL or pfd_DoubleBuffer;
  iPixelType := pfd_Type_RGBA;
  cColorBits := 24;      cDepthBits := 32;
  iLayerType := pfd_Main_Plane;
  end;
nPixelFormat := ChoosePixelFormat(CanHandle, @PFD);
SetPixelFormat(CanHandle, nPixelFormat, @PFD);
Result := wglCreateContext(CanHandle);   { Rendering Context }
end;

{========= Рендеринг рисунка в Bitmap с заданными размерами ==========}

procedure TForm1.RenderToBitmap(ABitmap: TBitmap);
var FrameBuffer: TFrameBuffer;
var MyDC: HDC;   GhostForm: TForm;
Err:byte;
FGLContext:HGLRC;
s:string;
begin
glFinish;    { Добавлено 18.11.11: ждём завершения всех GL-операций }
 ABitmap:=TBitmap.Create;
Abitmap.PixelFormat := pf24bit;   { С другими не пойдёт }
          ABitmap.SetSize(DrawTrans.Width,DrawTrans.Height);
          ABitmap.SetSize(DrawTrans.Width,DrawTrans.Height);

ABitmap.Canvas.Lock;
{ Вспомогательная невидимая форма }
GhostForm := TForm.Create(Self);
GhostForm.ClientWidth := ABitmap.Width;
GhostForm.ClientHeight := ABitmap.Height;
{ Получаем контекст для вспомогательной невидимой формы }
MyDC := GetDC(GhostForm.Handle);
FGLContext := GetScreenContext(MyDC);
wglMakeCurrent(MyDC, FGLContext);


FrameBuffer := TFrameBuffer.Create(ABitmap, Err);
   If Err = 0 then begin
{....... Инициализация матриц проектирования и моделирования .........}
//   SetMatrixes(ABitmap.Width, ABitmap.Height);

			p:=tprogr.create(PanelErr{Trans},PanelEdit,DrawTrans,progress,false);
      p.is3D:=false;//is3D;
			p.name:='ProgrTransl';
			p.isDrawBorderProgr:=true;
			p.isDrawEkvid:=false;//true;
      DrawTrans.fprogr:=p;
      p.open(DialogLoadSave.FileName);
      p.width_ekvid:=0;//Form_Const_Tools_New_DC_Width_sharp.Value/10;
      p.isCirclePrir:=progr.isCirclePrir;
      p.RaznRadius:=progr.RaznRadius;
      p.isSkipCadr:=progr.isSkipCadr;
      p.EkvidPodxod:= progr.EkvidPodxod;
      if (isShowProgr) then
        ShowIconOrProgr(false);
      if p.tip=typeESSI then
        sExt:=ext_esi
      else
        if p.tip=typeISO then
          sExt:=ext_iso;
     sExt:=sExt+ext_pic;

			if p.compile(true) then
      begin
        Panel_Flash_Stop.SetError(Mes_NotError_LNG,cf_Message);

        DrawTrans.DrawToScreen(stDrawToScreenProgr);
        DrawTrans.repaint;

        S:=ChangeFileExt(p.fullname,sExt);
        FileSetAttr(S,faArchive);
      end;

          ABitmap.Canvas.CopyRect(Rect(0,0,ABitmap.width,ABitmap.Height),DrawTrans.Canvas,Rect(0,0,ABitmap.width,ABitmap.Height));

//   MyPaint(True);  { Рисуем на контексте функциями OpenGL }
   FrameBuffer.TextureToBitmap;

         gif:=TGIFImage.Create;
          gif.Assign(ABitmap);

          if SSS<>sExt then
           gif.SaveToFile(ChangeFileExt(p.fullname,sss))
          else
          gif.SaveToFile(ChangeFileExt(p.fullname,sExt));
          ABitmap.Free;
          gif.Free;

   end;
{....... Освобождение памяти и уничтожение временного контекста ......}
FrameBuffer.Free;        GhostForm.Free;
wglMakeCurrent(0, 0);   // wglDeleteContext(FGLContext);
FGLContext := 0;    { Признак - см. proc.MyPaint }
ABitmap.Canvas.UnLock;


end;

Это реализация того что с GL, GLu, GLext: но как и писал выше не пробовал, т.к. не могу найти эти модули.
(*
procedure TForm1.RenderToBitmap(const ABitmap: TBitmap);
var FormatIndex: Integer;    PFD: TPixelFormatDescriptor;  lFDC: HDC;
FGLContext:HGLRC;
begin
lFDC := ABitmap.Canvas.Handle;
FillChar(PFD, SizeOf(PFD), 0);
  With PFD do begin
  nSize := SizeOf(PFD);   nVersion := 1;
  dwFlags := pfd_Draw_to_Bitmap or pfd_Support_OpenGL;
  iPixelType := pfd_Type_RGBA;
  cColorBits := 24;    cDepthBits := 32;
  iLayerType := pfd_Main_Plane;
  end;
FormatIndex := ChoosePixelFormat(lFDC, @PFD);
SetPixelFormat(lFDC, FormatIndex, @PFD);
FGLContext := wglCreateContext(lFDC);
wglMakeCurrent(lFDC, FGLContext);
//MyPaint(True);
        DrawTrans.DrawToScreen(stDrawToScreenProgr);
        DrawTrans.repaint;
      //    ABitmap:=TBitmap.Create;

          ABitmap.PixelFormat:=pf24bit;
          ABitmap.SetSize(PanelTrans.Width,PanelTrans.Height);
          ABitmap.SetSize(PanelTrans.Width,PanelTrans.Height);
          ABitmap.Canvas.CopyRect(Rect(0,0,ABitmap.width,ABitmap.Height),DrawTrans.Canvas,Rect(0,0,ABitmap.width,ABitmap.Height));
          gif.Assign(ABitmap);
end;
*)


******************************************
Это трансляция картинки gif:
	TDRawPicture = class (TGraphicControl)
DrawTrans:TDRawPicture;

procedure TForm1.Do_transl;
var
  s{,sExt}:string;
  gif:TGIFImage;
  b:TBitmap;
  i:integer;
  Sender:TObject;
  SSS:string;
  Stream1:TStream;
begin
  if (DialogLoadSave.FileName<>'') and (FileExists(DialogLoadSave.FileName)) then
  begin
    try
      SSS:=ExtractFileExt(DialogLoadSave.FileName)+'.GIF';

      ImageTrans.Visible:=false;
      PanelDraw.Visible:=false;
      PanelTrans.Visible:=true;

			p:=tprogr.create(PanelErr{Trans},PanelEdit,DrawTrans,progress,false);
      p.is3D:=false;//is3D;
			p.name:='ProgrTransl';
			p.isDrawBorderProgr:=true;
			p.isDrawEkvid:=false;//true;
      DrawTrans.fprogr:=p;
      p.open(DialogLoadSave.FileName);
      p.width_ekvid:=0;//Form_Const_Tools_New_DC_Width_sharp.Value/10;
      p.isCirclePrir:=progr.isCirclePrir;
      p.RaznRadius:=progr.RaznRadius;
      p.isSkipCadr:=progr.isSkipCadr;
      p.EkvidPodxod:= progr.EkvidPodxod;
      if (isShowProgr) then
        ShowIconOrProgr(false);
      if p.tip=typeESSI then
        sExt:=ext_esi
      else
        if p.tip=typeISO then
          sExt:=ext_iso;
     sExt:=sExt+ext_pic;

			if p.compile(true) then
      begin
        Panel_Flash_Stop.SetError(Mes_NotError_LNG,cf_Message);

        DrawTrans.DrawToScreen(stDrawToScreenProgr);
        DrawTrans.repaint;

        S:=ChangeFileExt(p.fullname,sExt);
        FileSetAttr(S,faArchive);

        try
          gif:=TGIFImage.Create;
          b:=TBitmap.Create;

          b.Width:=PanelTrans.Width;
          b.Height:=PanelTrans.Height;

          b.PixelFormat:=pf24bit;
          b.SetSize(PanelTrans.Width,PanelTrans.Height);
          b.SetSize(PanelTrans.Width,PanelTrans.Height);
          b.Canvas.CopyRect(Rect(0,0,b.width,b.Height),DrawTrans.Canvas,Rect(0,0,b.width,b.Height));
          gif.Assign(b);

          if SSS<>sExt then
           gif.SaveToFile(ChangeFileExt(p.fullname,sss))
          else
          gif.SaveToFile(ChangeFileExt(p.fullname,sExt));

        finally
          b.Free;
          gif.Free;
        end;

      end
      else
      begin
       System.SysUtils.DeleteFile(ChangeFileExt(p.fullname,sExt));
        Panel_Flash_STOP.SetError(Mes_Error__LNG,cf_Error);

      end;
      DialogLoadSave.DeActive;
    DialogLoadSave.Update;

  DialogLoadSave.FileList_SetFocus;
  DialogLoadSaveChangeFileList(Sender);
  finally
    p.Destroy;
    ImageTrans.Visible:=true;

    PanelTrans.Visible:=false;
  end;

  DialogLoadSave.FileList_SetFocus;
  if Panel_Flash_STOP.Status=cf_Error then
  begin
       PanelEdit.SetFocus;

  end;
end;
end;


*********************************
 (* unit FrameBufferUnit;

interface

uses
 Windows, SysUtils, Graphics, GL, GLu, GLext;

type
 TFrameBuffer = class
 private
   width   : Integer;
   height  : Integer;
   frameb  : GLuint;
   depthb  : GLuint;
   texture : GLuint;
   ftex    : boolean;
 public
   constructor Create(const nWidth,nHeight:Integer;ctexture:Integer = 0 );
   destructor Destroy;override;
   procedure BindFrameBuffer;
   procedure UnbindFrameBuffer;
   function GetBitmap:TBitmap;
   procedure AttachTexture;
   procedure DettachTexture;
 end;

implementation

{ TFrameBuffer }

type
 TRGBLine = array [0..1023] of TRGBTriple;
 PRGBLine = ^TRGBLine;

procedure TFrameBuffer.AttachTexture;
begin
glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT,GL_COLOR_ATTACHMENT0_EXT,GL_TEXTURE _2D,texture,0);
end;

procedure TFrameBuffer.BindFrameBuffer;
begin
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT,frameb);
end;

constructor TFrameBuffer.Create(const nWidth, nHeight: Integer;ctexture:Integer);
var
 res   : Integer;
 ww,hh : Integer;
begin
Width:=nWidth;
Height:=nHeight;
{ ww:=1;
while ww<Width do
 ww:=ww*2;
hh:=1;
while hh<Height do
 hh:=hh*2;}
ww:=Width;
hh:=Height;
ftex:=ctexture<>0;
if ftex then
 texture:=ctexture
else
 glGenTextures(1,@texture);
glBindTexture(GL_TEXTURE_2D,texture);
glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR_MIPMAP_LINEAR);
glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);
glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);
glTexParameterf(GL_TEXTURE_2D,GL_GENERATE_MIPMAP,0);
glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA8,ww,hh,0,GL_RGBA,GL_UNSIGNED_BYTE,nil);
glBindTexture(GL_Texture_2D,0);
glGenFramebuffersEXT(1,@frameb);
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT,frameb);
glGenRenderbuffersEXT(1,@depthb);
glBindRenderbufferEXT(GL_RENDERBUFFER_EXT,depthb);
glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT,GL_DEPTH_COMPONENT,width,height);
glBindRenderbufferEXT(GL_RENDERBUFFER_EXT,0);
glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT,GL_COLOR_ATTACHMENT0_EXT,GL_TEXTURE _2D,texture,0);
glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT,GL_DEPTH_ATTACHMENT_EXT,GL_RENDE RBUFFER_EXT,depthb);
res:=glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
if res<>GL_FRAMEBUFFER_COMPLETE_EXT then
 raise Exception.Create('frame buffer error');
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT,0);
end;

destructor TFrameBuffer.Destroy;
begin
DettachTexture;
glDeleteFramebuffersEXT(1,@frameb);
glDeleteRenderbuffersEXT(1,@depthb);
if not ftex then
 glDeleteTextures(1,@texture);
inherited;
end;

procedure TFrameBuffer.DettachTexture;
begin
glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT,GL_COLOR_ATTACHMENT0_EXT,GL_TEXTURE _2D,0,0);
end;

function TFrameBuffer.GetBitmap: TBitmap;
var
 buf : Pointer;
 l   : PRGBLine;
 b   : ^TRGBTriple;
 i,j : Integer;
 h,w : Integer;
function PtrAllign(APointer:Pointer; bytes: cardinal):Pointer;
begin
 Result := Ptr(cardinal(APointer) + (bytes-cardinal(APointer) mod bytes) mod bytes);
end;
begin
w:=width;
h:=height;
result:=TBitmap.Create;
result.PixelFormat:=pf24bit;
result.Width:=w;
result.Height:=h;
GetMem(buf,w*h*3);
glBindTexture(GL_TEXTURE_2D,texture);
ZeroMemory(buf,w*h*3);
glGetTexImage(GL_TEXTURE_2D,0,GL_RGB,GL_UNSIGNED_BYTE,buf);
glBindTexture(GL_TEXTURE_2D,0);
b:=buf;
for i:=h-1 downto 0 do
begin
  l:=result.ScanLine[i];
  for j:=0 to w-1 do
  begin
    l[j].rgbtBlue:=b.rgbtRed;
    l[j].rgbtGreen:=b.rgbtGreen;
    l[j].rgbtRed:=b.rgbtBlue;
    Inc(b);
  end;
  b:=PtrAllign(b,4);
end;
FreeMemory(buf);
end;

procedure TFrameBuffer.UnbindFrameBuffer;
begin
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT,0);
end;

end.


*)


unit FrameBufferUnit;
{=======  Работа с Frame Buffer Object для сохранения в Bitmap  ======}
interface

uses Windows, SysUtils, Graphics, OpenGL, Dialogs;




type TFrameBuffer = class
 private
   Width, Height: Integer;
   FrameBuf, DepthBuf, Texture: GLuint;
   Bitmap: TBitmap;
 public
   constructor Create(const TargetBitmap: TBitmap; out Err: byte);
   destructor Destroy; override;
   procedure TextureToBitmap;
 end;
{---------------------------------------------------------------------}
procedure glGenTextures(n: GLsizei; Textures: PGLuint);
 stdcall;   external 'opengl32.dll';
procedure glBindTexture(Target: GLenum; Texture: GLuint);
 stdcall;   external 'opengl32.dll';
procedure glDeleteTextures(n: GLsizei;
  const Textures: PGLuint); stdcall;  external 'opengl32.dll';
function wglGetProcAddress(ProcName: PAnsiChar): Pointer;
  stdcall; external 'opengl32.dll';
{---------------------------------------------------------------------}
implementation  { TFrameBuffer }

type TglFramebufferTexture2DEXT = procedure(Target: GLenum;
  Attachment: GLenum; TexTarget: GLenum;
  Texture: GLuint; level: GLint);  stdcall;
TglBindFramebufferEXT = procedure(Target: GLenum;
  FrameBuffer: GLuint); stdcall;
TglGenFramebuffersEXT = procedure(n: GLsizei;
  FrameBuffers: PGLuint); stdcall;
TglGenRenderbuffersEXT = procedure(n: GLsizei;
  RenderBuffers: PGLuint); stdcall;
TglBindRenderbufferEXT = procedure(Target: GLenum;
  RenderBuffer: GLuint); stdcall;
TglRenderbufferStorageEXT = procedure(Target: GLenum;
  InternalFormat: GLenum; Width: GLsizei; Height: GLsizei); stdcall;
TglFramebufferRenderbufferEXT = procedure(target: GLenum; Attachment:
  GLenum; RenderBufferTarget: GLenum; renderbuffer: GLuint); stdcall;
TglCheckFramebufferStatusEXT = function(Target:GLenum):GLenum; stdcall;
TglDeleteFramebuffersEXT = procedure(n: GLsizei;
  const FrameBuffers: PGLuint); stdcall;
TglDeleteRenderbuffersEXT = procedure(n: GLsizei;
  const RenderBuffers: PGLuint); stdcall;

var glFramebufferTexture2DEXT: TglFramebufferTexture2DEXT;
    glBindFramebufferEXT: TglBindFramebufferEXT;
    glGenFramebuffersEXT: TglGenFramebuffersEXT;
    glGenRenderbuffersEXT: TglGenRenderbuffersEXT;
    glBindRenderbufferEXT: TglBindRenderbufferEXT;
    glRenderbufferStorageEXT: TglRenderbufferStorageEXT;
    glFramebufferRenderbufferEXT: TglFramebufferRenderbufferEXT;
    glCheckFramebufferStatusEXT: TglCheckFramebufferStatusEXT;
    glDeleteFramebuffersEXT: TglDeleteFramebuffersEXT;
    glDeleteRenderbuffersEXT: TglDeleteRenderbuffersEXT;
const
  gl_FrameBuffer_EXT = $8D40;
  gl_Color_Attachment0_EXT = $8CE0;
  gl_Generate_MipMap = $8191;
  gl_RGBA8 = $8058;
  gl_RenderBuffer_EXT = $8D41;
  gl_Depth_Attachment_EXT = $8D00;
  gl_FrameBuffer_COMPLETE_EXT = $8CD5;
  gl_BGR = $80E0;
{===============================================================}
constructor TFrameBuffer.Create(const TargetBitmap: TBitmap;
 out Err: Byte);
begin
Err := 0;
If Pos(PAnsiChar('GL_EXT_framebuffer_object'),
 glGetString(gl_Extensions)) = 0 then Err := 1;
   If Err = 1 then begin MessageDlg(
    'No FrameBuffer Extensions. Refresh VIDEO drivers !',
   mtWarning, [mbCancel], 0);
   Exit;
   end;
{........... Загружаем внешние функции-расширения OpenGL .............}
glFramebufferTexture2DEXT :=
  wglGetProcAddress('glFramebufferTexture2DEXT');
glGenFramebuffersEXT := wglGetProcAddress('glGenFramebuffersEXT');
glBindFramebufferEXT := wglGetProcAddress('glBindFramebufferEXT');
glGenRenderbuffersEXT := wglGetProcAddress('glGenRenderbuffersEXT');
glBindRenderbufferEXT := wglGetProcAddress('glBindRenderbufferEXT');
glRenderbufferStorageEXT :=
 wglGetProcAddress('glRenderbufferStorageEXT');
glFramebufferRenderbufferEXT :=
 wglGetProcAddress('glFramebufferRenderbufferEXT');
glCheckFramebufferStatusEXT :=
 wglGetProcAddress('glCheckFramebufferStatusEXT');
glDeleteFramebuffersEXT:= wglGetProcAddress('glDeleteFramebuffersEXT');
glDeleteRenderbuffersEXT :=
 wglGetProcAddress('glDeleteRenderbuffersEXT');
{............... Генерация и инициализация текстуры ..................}
Bitmap := TargetBitmap;
Width := Bitmap.Width;   Height := Bitmap.Height;
   Try
   glGenTextures(1, @Texture);
   glBindTexture(gl_Texture_2D, Texture);
   glTexParameterf(gl_Texture_2D, gl_Texture_Mag_Filter, gl_Linear);
   glTexParameterf(gl_Texture_2D, gl_Texture_Mag_Filter,
    gl_Linear_MipMap_Linear);
   glTexParameterf(gl_Texture_2D, gl_Texture_Wrap_S, gl_Repeat);
   glTexParameterf(gl_Texture_2D, gl_Texture_Wrap_T, gl_Repeat);
   glTexParameterf(gl_Texture_2D, gl_Generate_MipMap,0);
   glTexImage2D(gl_Texture_2D, 0, gl_RGBA8, Width, Height,
    0, gl_RGBA, gl_UnSigned_Byte, nil);
   glBindTexture(gl_Texture_2D, 0);
{............  Присоединяем Frame- и Render-buffers  .................}
   glGenFramebuffersEXT(1, @FrameBuf);
   glBindFramebufferEXT(gl_FrameBuffer_EXT, FrameBuf);
   glGenRenderbuffersEXT(1, @DepthBuf);
   glBindRenderbufferEXT(gl_RenderBuffer_EXT, DepthBuf);
   glRenderbufferStorageEXT(gl_RenderBuffer_EXT, gl_Depth_Component,
    Width, Height);
   glBindRenderbufferEXT(gl_RenderBuffer_EXT, 0);
   glFramebufferTexture2DEXT(gl_FrameBuffer_EXT,
    gl_Color_Attachment0_EXT, gl_Texture_2D, Texture, 0);
   glFramebufferRenderbufferEXT(gl_FrameBuffer_EXT,
    gl_Depth_Attachment_EXT, gl_RenderBuffer_EXT, DepthBuf);
{............... Проверка успешности инициализации ...................}
   If glCheckFramebufferStatusEXT(gl_FrameBuffer_EXT) <>
    gl_FrameBuffer_Complete_EXT then Err := 2;
{ Присоединяем Texture }
   glFramebufferTexture2DEXT(gl_FrameBuffer_EXT,
    gl_Color_Attachment0_EXT, gl_Texture_2D, Texture, 0);
   except
   Err := 2;
   end;
If Err = 2 then MessageDlg('Frame Buffer creation not complete !',
 mtWarning, [mbCancel], 0);
end;

{========= Уничтожение вспомогательных буферов и текстуры ============}
destructor TFrameBuffer.Destroy;
begin
{ Отключение и уничтожение RenderBuffer }
glBindRenderbufferEXT(gl_RenderBuffer_EXT, 0);
glDeleteRenderbuffersEXT(1, @DepthBuf);
{ Отключение и уничтожение FrameBuffer }
glBindFramebufferEXT(gl_FrameBuffer_EXT, 0);
glDeleteFramebuffersEXT(1, @FrameBuf);
{ Отключение и уничтожение Texture }
glBindTexture(gl_Texture_2D, 0);
glDeleteTextures(1, @Texture);
inherited Destroy;
end;

{=============== Сохранение текстуры в TargetBitmap ==================}
procedure TFrameBuffer.TextureToBitmap;
var TBuf, Buf ,Pline: Pointer;   I: Integer;
begin
Buf := nil;
   Try
   GetMem(Buf, Width * Height * 3);
   glPixelStorei(gl_Pack_Alignment, 1);
   glBindTexture(gl_Texture_2D, Texture);
   glGetTexImage(gl_Texture_2D, 0, gl_BGR, gl_UnSigned_Byte, Buf);
   TBuf := Buf;
      For I := Height - 1 downto 0 do begin
      Pline := Bitmap.ScanLine[i];
      Move(TBuf^, Pline^, Width*3);
      Inc(NativeInt(TBuf), Width*3);
      end;
   finally
   FreeMemory(Buf);
   end;
end;

end.