gistfile1.txt

void D3DVideo::viewport_size(unsigned &width, unsigned &height)
{
   width  = final_viewport.Width;
   height = final_viewport.Height;
}

bool D3DVideo::read_viewport(uint8_t *buffer)
{
   bool ret = true;
   IDirect3DSurface9 *target = nullptr;
   IDirect3DSurface9 *dest   = nullptr;

   if (FAILED(dev->GetRenderTarget(0, &target)))
   {
      ret = false;
      goto end;
   }

   if (FAILED(dev->CreateOffscreenPlainSurface(screen_width, screen_height,
        D3DFMT_X8R8G8B8, D3DPOOL_SYSTEMMEM,
        &dest, nullptr)))
   {
      ret = false;
      goto end;
   }

   if (FAILED(dev->GetRenderTargetData(target, dest)))
   {
      ret = false;
      goto end;
   }

   D3DLOCKED_RECT rect;
   if (SUCCEEDED(dest->LockRect(&rect, nullptr, D3DLOCK_READONLY)))
   {
      unsigned pitchpix = rect.Pitch / 4;
      const uint32_t *pixels = (const uint32_t*)rect.pBits;
      pixels += final_viewport.X;
      pixels += (final_viewport.Height - 1) * pitchpix;
      pixels -= final_viewport.Y * pitchpix;

      for (unsigned y = 0; y < final_viewport.Height; y++, pixels -= pitchpix)
      {
         for (unsigned x = 0; x < final_viewport.Width; x++)
         {
            *buffer++ = (pixels[x] >>  0) & 0xff;
            *buffer++ = (pixels[x] >>  8) & 0xff;
            *buffer++ = (pixels[x] >> 16) & 0xff;
         }
      }

      dest->UnlockRect();
   }
   else
   {
      ret = false;
      goto end;
   }

end:
   if (target)
      target->Release();
   if (dest)
      dest->Release();
   return ret;
}