L_ProcessPlayback

#include "l_bitmap.h"

L_LTDIS_API L_INT L_ProcessPlayback(hPlayback, puState)

Processes the next state during an animation playback.

Parameters

HPLAYBACK hPlayback

Handle that references the animation playback.

L_UINT* puState

Address of the variable to be updated with a constant that describes the new state of the animation playback engine. For possible values, refer to Animation Playback States.

Returns

Value Meaning
SUCCESS The function was successful.
< 1 An error occurred. Refer to Return Codes.

Comments

This function does not support signed data images. It returns the error code ERROR_SIGNED_DATA_NOT_SUPPORTED if a signed data image is passed to this function.

This function is called in a loop to continually process the playback.

Required DLLs and Libraries

Platforms

Win32, x64, Linux.

See Also

Functions

Topics

Example

For an example, refer to L_AppendPlayback.
This example loads a bitmap list from an animated GIF or AVI file.
It then plays the animation, using the current bitmap as the target.

L_INT ProcessPlaybackExample(L_HWND           hWnd, 
                                             pBITMAPHANDLE  pBitmap, 
                                             L_TCHAR*       pszFilename, 
                                             HPALETTE       hpalPaint) 
{ 
   L_INT nRet; 
   HBITMAPLIST    hList;            /* Bitmap list */ 
   BITMAPHANDLE   TmpBitmap;        /* Temporary bitmap for building the list */ 
   HPLAYBACK      hPlayback;        /* Animation playback */ 
   L_UINT         uState;           /* Next state in the playback */ 
   RECT           rcUpdate;         /* Source clipping rectangle used in playback */ 
   RECT           rcDisplay;        /* Display rectangle used in playback */ 
   HDC            hdc;              /* Device context of the current window */ 
   HPALETTE       hPalette = NULL;  /* Temporary copy of the current system palette */ 
 
   /* Create the bitmap list from the input file (GIF or AVI) */ 
   nRet = L_LoadBitmapList(pszFilename, &hList, 0, 0, NULL, NULL); 
   if(nRet != SUCCESS) 
      return nRet; 
   /* Get a copy of the first image's bitmap handle */ 
   nRet = L_GetBitmapListItem(hList, 0, &TmpBitmap, sizeof(BITMAPHANDLE)); 
   if(nRet != SUCCESS) 
      return nRet; 
   /* Create the palette that is used for playback */ 
   hdc = GetDC (hWnd); 
   hpalPaint = L_CreatePaintPalette(hdc, &TmpBitmap); 
   ReleaseDC (hWnd, hdc); 
   /* Use the client area as the display rectangle,  
   assuming that the window is properly sized */ 
   GetClientRect(hWnd,&rcDisplay); 
   /* Create the target bitmap that is used for playback */ 
   if(pBitmap->Flags.Allocated) 
      L_FreeBitmap(pBitmap); 
   nRet = L_CreateBitmap(pBitmap, sizeof(BITMAPHANDLE), TYPE_CONV, 
               TmpBitmap.Width, 
               TmpBitmap.Height, 
               TmpBitmap.BitsPerPixel, 
               TmpBitmap.Order, 
               NULL, 
               TmpBitmap.ViewPerspective, NULL, 0); 
   if(nRet != SUCCESS) 
      return nRet; 
   /* Update the palette of the target bitmap */ 
   nRet = L_CopyBitmapPalette(pBitmap, &TmpBitmap); 
   if(nRet != SUCCESS) 
      return nRet; 
   /* Create and run the playback */ 
   nRet = L_CreatePlayback(&hPlayback, pBitmap, hList); 
   if(nRet != SUCCESS) 
      return nRet; 
   do 
   { 
      nRet = L_ProcessPlayback(hPlayback, &uState); 
      if(nRet != SUCCESS) 
         return nRet; 
      switch(uState) 
      { 
      case PLAYSTATE_WAITINPUT: 
            nRet = L_CancelPlaybackWait(hPlayback); 
            if(nRet != SUCCESS) 
               return nRet; 
            break; 
      case PLAYSTATE_POSTCLEAR: 
      case PLAYSTATE_POSTRENDER: 
         nRet = L_GetPlaybackUpdateRect(hPlayback, &rcUpdate, TRUE); 
         if(nRet != SUCCESS) 
            return nRet; 
         hdc = GetDC(hWnd); 
         if (hpalPaint) 
         { 
            hPalette = SelectPalette (hdc, hpalPaint, TRUE); 
            RealizePalette(hdc); 
         } 
         nRet = L_PaintDC(hdc, pBitmap, NULL, &rcUpdate, &rcDisplay, &rcDisplay, SRCCOPY); 
         if(nRet != SUCCESS) 
            return nRet; 
         if (hpalPaint) 
            SelectPalette (hdc, hPalette, TRUE); 
         ReleaseDC(hWnd, hdc); 
         break; 
      } 
   } while(uState != PLAYSTATE_END); 
   /* Clean up */ 
   L_DestroyPlayback(hPlayback, NULL); 
   L_DestroyBitmapList(hList); 
   return SUCCESS; 
} 

Help Version 21.0.2021.3.4
Products | Support | Contact Us | Intellectual Property Notices
© 1991-2021 LEAD Technologies, Inc. All Rights Reserved.

LEADTOOLS Raster Imaging C API Help