https://youtu.be/voVpbZGhaRY

aviSys2.inl

void AVISceneRenderEx()
{
  auto&Dev=D9Dev;
  vec2i ClientSize=win.GetClientSize();
  if(!Dev.BeginScene())return;
  {
    D3DVIEWPORT9 ViewPort={0,0,ClientSize.x,ClientSize.y,-1.f,+1.f};
    Dev.pDev->SetViewport(&ViewPort);
    Dev.Set2D(vec2i(0,0),1.0,0,&ClientSize);
    Dev.Clear2D(0xffc8c8c8);
    qDev.NextFrame();
    SceneDoDraw();
  }
  if(!Dev.EndScene())return;
}
void UpdateAVISYS2(const string&fn="foo.avi",int FPS=60,int onkey=VK_F9){
  auto&rec=avirecsys2;
  if(kb.OnDown(onkey)){
    inv(rec.enabled);
    if(rec.enabled)rec.start(this,fn);
    if(!rec.enabled)rec.stop();
  }
  rec.update(FPS);
}
template<class TGame>
struct t_avirecsys2:t_avi{
  #define DEF_PRO_VARIABLE(ADD)\
  ADD(bool,enabled,false)\
  ADD(IDirect3DSurface9*,surface,nullptr)\
  ADD(IDirect3DSurface9*,rt,nullptr)\
  ADD(IDirect3DSurface9*,pold,nullptr)\
  ADD(TGame*,pgame,nullptr)\
  ADD(QapTexMem,mem,mem)\
  //===
  #include "defprovar.inl"
  //===
  t_avirecsys2(){DoReset();}
 ~t_avirecsys2(){stop();}
  void start(TGame*pgame,const string&fn){
    this->pgame=pgame;
    auto&pDev=pgame->qDev.pDev;
    QapAssert(!surface&&!rt&&!pold);
    auto sm=GetScreenMode();auto W=sm.W;auto H=sm.H;mem.Init(W,H);
    pDev->CreateRenderTarget(W,H,pgame->D9Dev.PresParams.pp.BackBufferFormat,D3DMULTISAMPLE_NONE,0,0,&rt,0);
    pDev->CreateOffscreenPlainSurface(W,H,pgame->D9Dev.PresParams.pp.BackBufferFormat,D3DPOOL_SYSTEMMEM,&surface,NULL);
    QapAssert(rt);QapAssert(surface);
    START_AVI(fn.c_str());
  }
  template<class TYPE>static void comfree(TYPE*&ptr){if(ptr)ptr->Release();ptr=nullptr;}
  void stop(){
    if(!surface)return;
    STOP_AVI();
    comfree(surface);comfree(rt);comfree(pold);
  }
  void update(int FPS){
    if(!enabled){return;}
    auto&pDev=pgame->qDev.pDev;
    
    QapAssert(surface&&rt&&!pold);
    pDev->GetRenderTarget(0,&pold);
    pDev->SetRenderTarget(0,rt);
    QapAssert(pold);
    pgame->AVISceneRenderEx();
    if(pDev->GetRenderTargetData(rt,surface)){QapDebugMsg("GetFrontBufferData - failed");return;}
    {
      D3DLOCKED_RECT LockedRect;
      surface->LockRect(&LockedRect,NULL,D3DLOCK_READONLY);
      auto*p=(QapColor*)LockedRect.pBits;
      auto W=mem.W;auto H=mem.H;QapColor*pix=mem.get();
      for(int y=0;y<H;y++)for(int x=0;x<W;x++)pix[(H-y-1)*W+x]=p[y*W+x];
      QapBitmapInfo QBI(W,H);ADD_FRAME_FROM_DIB_TO_AVI(&QBI.BH,pix,"XVID",FPS);
      surface->UnlockRect();
    }
    pDev->SetRenderTarget(0,pold);
    comfree(pold);
  }
  bool is_avi_pass()const{return pold;}
};
t_avirecsys2<TGame> avirecsys2;
bool is_avi_pass()const{return avirecsys2.is_avi_pass();}