使用 directfb绘制图像（draw image with directfb）

最新推荐文章于 2021-05-17 09:22:58 发布

原创最新推荐文章于 2021-05-17 09:22:58 发布 · 690 阅读

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CC 4.0 BY-SA版权

文章标签：

#image #null #events #layer #licensing #file

本文档详细介绍了如何使用DirectFB库在Linux环境下初始化帧缓冲，并创建和管理DirectFB表面，用于在全屏模式下绘制图像。代码示例包括了创建和释放DirectFB对象、设置合作级别、创建输入事件缓冲区、处理鼠标事件以及更新屏幕显示。此外，还展示了如何在屏幕上绘制鼠标光标并处理鼠标移动。

/**********************************************************************
** Copyright (C) 2010 FreeC ORG. All rights reserved.
** Author: Carlson Lee.
**
** This file is part of FreeC.
**
** This file may be distributed and/or modified under the terms of the
** GNU General Public License version 2 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
** See http://freec.sourceforge.net
**
** Contact CarlsonLee_FreeC@hotmail.com if any conditions of this licensing are
** not clear to you.
**
**********************************************************************/

#include "config.h"
#include "typedef.h"
#include <linux/fb.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
//#include <asm/page.h>
#include <sys/mman.h>
#include <directfb.h>

#include <asm/errno.h>
#include <pthread.h>
#include "errcode.h"
#include "cncui.h"
#include "disp.h"
#include "cncdisplay.h"
#include "cnctask.h"

static IDirectFB *dfb = NULL;
static IDirectFBSurface *primary = NULL;
static IDirectFBDisplayLayer *layer = NULL;
static IDirectFBSurface *imageSurface = NULL;
static IDirectFBEventBuffer *mouse_events = NULL;

static pthread_mutex_t mutex_display = PTHREAD_MUTEX_INITIALIZER;

static UINT8 *pCursorBuf = NULL;
static UINT8 *mouse_bg_data = NULL;

#define DFBCHECK(x...)                                         /
{                                                            /
   DFBResult err = x;                                         /
   if (err != DFB_OK)                                         /
   {                                                        /
       printf("%s <%d>:/n/t", __FILE__, __LINE__ ); /
       DirectFBErrorFatal( #x, err );                         /
       goto exit;                                           /
   }                                                        /
}
#define MOUSE_WIDTH       12
#define MOUSE_HEIGHT   20

/* init framebuffer*/
CNC_RET dispInit(void)
{
   DFBSurfaceDescription dsc;
   pthread_t key_thread_id;

   if(dfb || primary || imageSurface)
       return CERR_NONE;

   DFBCHECK (DirectFBInit (0, 0));
   DFBCHECK (DirectFBCreate (&dfb));
   DFBCHECK (dfb->SetCooperativeLevel (dfb, DFSCL_FULLSCREEN));
   dsc.flags = DSDESC_CAPS | DSDESC_WIDTH | DSDESC_HEIGHT | DSDESC_PIXELFORMAT;
   dsc.caps = DSCAPS_PRIMARY;
   dsc.width   = SCREEN_WIDTH;
   dsc.height   = SCREEN_HEIGHT;
//#if BYTES_PER_PIXEL==3
//   dsc.pixelformat = DSPF_RGB24 ;
//#elif BYTES_PER_PIXEL==4
   dsc.pixelformat = DSPF_RGB32 ;
   dfb->GetDisplayLayer(dfb, 0, &layer);
   layer->EnableCursor(layer, 1);
//#endif
   DFBCHECK (dfb->CreateSurface( dfb, &dsc, &primary ));
   dsc.flags = DSDESC_WIDTH | DSDESC_HEIGHT | DSDESC_PIXELFORMAT;
   dsc.width   = SCREEN_WIDTH;
   dsc.height   = SCREEN_HEIGHT;
//#if BYTES_PER_PIXEL==3
//   dsc.pixelformat = DSPF_RGB24 ;
//#elif BYTES_PER_PIXEL==4
   dsc.pixelformat = DSPF_RGB32 ;
//#endif
   DFBCHECK(dfb->CreateSurface( dfb, &dsc, &imageSurface));
   DFBCHECK(dfb->CreateInputEventBuffer( dfb, DICAPS_ALL,
                                   DFB_FALSE, &mouse_events));
   printf("pthread_create procKeyMsg /n");

   if(0 != pthread_create(&key_thread_id,NULL,procKeyMsg,NULL))
   {
       printf("pthread_create procKeyMsg failed/n");
       goto exit;
   }
   pCursorBuf = (UINT8*)malloc(4*60*BYTES_PER_PIXEL);
   mouse_bg_data = (UINT8*)malloc(SCREEN_WIDTH*SCREEN_HEIGHT*4);
   return CERR_NONE;
exit:
   if(mouse_events)
       mouse_events->Release( mouse_events );
   if(imageSurface)
       imageSurface->Release( imageSurface );
   if(primary)
       primary->Release( primary );
   if(layer)
       layer->Release( layer );
   if(dfb)
       dfb->Release( dfb );
   return CERR_DISPLAY_INIT_FAIL;
}

void dispUninit()
{
   if(mouse_events)
       mouse_events->Release( mouse_events );
   if(imageSurface)
       imageSurface->Release( imageSurface );
   if(primary)
       primary->Release( primary );
   if(layer)
       layer->Release( layer );
   if(dfb)
       dfb->Release( dfb );
   if(pCursorBuf)
    {
        free(pCursorBuf);
        pCursorBuf = NULL;
    }
   if(mouse_bg_data)
    {
        free(mouse_bg_data);
        mouse_bg_data = NULL;
    }

   mouse_events = NULL;
   imageSurface = NULL;
   primary = NULL;
   dfb = NULL;
   pthread_mutex_destroy(&mutex_display);
}

const unsigned char mouse_data[720] =
{
   0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x01, 0x01, 0x01, 0xFF, 0xFF,
   0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x01,
   0x01, 0x01, 0x01, 0x01, 0x01, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0xFF, 0xFF, 0xFF, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0xFF, 0xFF, 0xFF, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
   0x01, 0x01, 0x01, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x01, 0x01, 0x01, 0x01, 0x01,
   0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x01,
   0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
   0x01, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0xFF, 0xFF, 0xFF, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
   0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
   0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0xFF,
   0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x01, 0x01, 0x01, 0x01, 0x01,
   0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
   0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x01,
   0x01, 0x01, 0x01, 0x01, 0x01, 0xFF, 0xFF, 0xFF, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0xFF, 0xFF,
   0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0xFF, 0xFF, 0xFF, 0x01, 0x01, 0x01, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x01,
   0x01, 0x01, 0x01, 0x01, 0x01, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0xFF, 0xFF, 0xFF, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
   0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x01, 0x01,
   0x01, 0x01, 0x01, 0x01, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0xFF, 0xFF, 0xFF, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0xFF,
   0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF,
   0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};

static int old_mouse_x = MOUSE_WIDTH/2;
static int old_mouse_y = MOUSE_HEIGHT/2;
static int old_mouse_width = -1;
static int old_mouse_height = -1;
static BOOL gbMouseShow = FALSE;

void    dispHideMouse()
{
   gbMouseShow = FALSE;
}

static void dispUpdateMouse(int x, int y)
{
   UINT8* display_buf = NULL;
   int display_buf_len = 0;
   DFBRectangle oldrect = {0,0,0,0};
   int mouse_width = MOUSE_WIDTH;
   int mouse_height = MOUSE_HEIGHT;
   int i, j;

   if(dfb==NULL || primary==NULL || imageSurface == NULL)
       return;

   if(x<0 || y<0 || x>=SCREEN_WIDTH || y>=SCREEN_HEIGHT)
       return;

   if(pthread_mutex_trylock(&mutex_display) == EBUSY)
        return;

   DFBCHECK(imageSurface->Lock(imageSurface, DSLF_WRITE, (void*)&display_buf, &display_buf_len));
   //copy old mouse bg buffer to screen
   if(old_mouse_x >=0 && old_mouse_y>=0 && old_mouse_width> 0 && old_mouse_height>0 && gbMouseShow)
   {
       if(old_mouse_x+MOUSE_WIDTH>SCREEN_WIDTH)
       {
           mouse_width = SCREEN_WIDTH - old_mouse_x;
       }
       if(old_mouse_y+MOUSE_HEIGHT>SCREEN_HEIGHT)
       {
           mouse_height = SCREEN_HEIGHT - old_mouse_y;
       }
       for(i=0; i<mouse_height; i++)
       {
           memcpy(display_buf+((old_mouse_y+i)*SCREEN_WIDTH+old_mouse_x)*BYTES_PER_PIXEL, mouse_bg_data+(i*MOUSE_WIDTH*BYTES_PER_PIXEL),mouse_width*BYTES_PER_PIXEL);
       }
       oldrect.x = old_mouse_x;
       oldrect.y = old_mouse_y;
       oldrect.w = mouse_width;
       oldrect.h = mouse_height;
   }

   //copy new mouse bg to old mouse bg buffer
   {
       if(x+MOUSE_WIDTH>SCREEN_WIDTH)
       {
           mouse_width = SCREEN_WIDTH - x;
       }
       if(y+MOUSE_HEIGHT>SCREEN_HEIGHT)
       {
           mouse_height = SCREEN_HEIGHT - y;
       }
       for(i=0; i<mouse_height; i++)
       {
           memcpy(mouse_bg_data+(i*MOUSE_WIDTH*BYTES_PER_PIXEL), display_buf+((y+i)*SCREEN_WIDTH+x)*BYTES_PER_PIXEL, mouse_width*BYTES_PER_PIXEL);
       }
       gbMouseShow = TRUE;
   }
   //set mouse icon to new place
   {
       //unsigned char *pTmp = mouse_data;
       if(x+MOUSE_WIDTH>SCREEN_WIDTH)
       {
           mouse_width = SCREEN_WIDTH - x;
       }
       if(y+MOUSE_HEIGHT>SCREEN_HEIGHT)
       {
           mouse_height = SCREEN_HEIGHT - y;
       }
       for(i=0; i<mouse_height; i++)
       {
           unsigned char* pTmp = (unsigned char*)mouse_data + i*MOUSE_WIDTH*3;
           for(j=0; j<mouse_width; j++)
           {
               if(*pTmp != 0x00)
               {
                   *(display_buf+((y+i)*SCREEN_WIDTH+x+j)*BYTES_PER_PIXEL) = *pTmp;
                   *(display_buf+((y+i)*SCREEN_WIDTH+x+j)*BYTES_PER_PIXEL+1) = *pTmp;
                   *(display_buf+((y+i)*SCREEN_WIDTH+x+j)*BYTES_PER_PIXEL+2) = *pTmp;
               //   *(display_buf+((y+i)*SCREEN_WIDTH+x+j)*BYTES_PER_PIXEL+3) = 0xFF;
               }
               pTmp+=3;
           }
       }
       old_mouse_x = x;
       old_mouse_y = y;
       old_mouse_width = mouse_height;
       old_mouse_height = mouse_width;
   }

   DFBCHECK(imageSurface->Unlock(imageSurface));
    primary->Blit (primary, imageSurface, &oldrect, oldrect.x, oldrect.y);
   oldrect.x = x;
   oldrect.y = y;
   oldrect.h = mouse_height;
   oldrect.w = mouse_width;
    primary->Blit (primary, imageSurface, &oldrect, oldrect.x, oldrect.y);
exit:
   pthread_mutex_unlock(&mutex_display);
   return;
}

int mouse_x = SCREEN_WIDTH/2;
int mouse_y = SCREEN_HEIGHT/2;

void* procKeyMsg(void* pParam)
{
   DFBInputEvent evt;

   mouse_events->WaitForEvent( mouse_events );
   cncTask_SetKeyThreadExited(FALSE);
   while (mouse_events->GetEvent( mouse_events, DFB_EVENT(&evt) ) == DFB_OK)
   {
       switch (evt.type)
       {
       case DIET_KEYRELEASE:
           cncDisp_ProcMsg(UI_OPERATE_KEYUP, evt.key_symbol, 0);
           break;
       case DIET_KEYPRESS:
           cncDisp_ProcMsg(UI_OPERATE_KEYDOWN, evt.key_symbol, 0);
           break;
        case DIET_BUTTONPRESS:
           if(evt.buttons & DIBM_LEFT)
           {
               UINT32 lParam = ((mouse_y<<16)&0xFFFF0000)+mouse_x;
               cncDisp_ProcMsg(UI_OPERATE_LBTN_DOWN, 0, lParam);
           }
           if(evt.buttons & DIBM_RIGHT)
           {
               cncTask_SetExit(TRUE);
           }
           break;
       case DIET_BUTTONRELEASE:
           if(evt.button == DIBI_LEFT)
           {
               UINT32 lParam = ((mouse_y<<16)&0xFFFF0000)+mouse_x;
               cncDisp_ProcMsg(UI_OPERATE_LBTN_UP, 0, lParam);
           }
           break;
         case DIET_AXISMOTION:
       {
           if (evt.flags & DIEF_AXISREL)
           {
               switch (evt.axis)
               {
               case DIAI_X:
                    mouse_x += evt.axisrel;
                    break;
               case DIAI_Y:
                    mouse_y += evt.axisrel;
                    break;
               default:
                break;
               }
           }
           if(mouse_x>=SCREEN_WIDTH)
           {
               mouse_x =SCREEN_WIDTH-1;
           }
           if(mouse_x<0)
           {
               mouse_x =0;
           }
           if(mouse_y>=SCREEN_HEIGHT)
           {
               mouse_y =SCREEN_HEIGHT-1;
           }
           if(mouse_y<0)
           {
               mouse_y =0;
           }
           dispUpdateMouse(mouse_x,mouse_y);
           {
               UINT32 lParam = ((mouse_y<<16)&0xFFFF0000)+mouse_x;
               cncDisp_ProcMsg(UI_OPERATE_MOUSE_MOVE, 0, lParam);
           }
       }
       default:
           break;
       }
       if(cncTask_GetExit())
           break;
       mouse_events->WaitForEvent( mouse_events );
   }
   cncTask_SetKeyThreadExited(TRUE);

   return NULL;
}

void dispUpdateScreen()
{
   void* display_buf = NULL;
   int display_buf_len = 0;
   int i, j;
   const DFBRectangle rect = {0,0, SCREEN_WIDTH, SCREEN_HEIGHT};
   if(dfb==NULL || primary==NULL || imageSurface == NULL)
       return;

   if(pthread_mutex_trylock(&mutex_display) == EBUSY)
       return;
   disp_num++;
   DFBCHECK(imageSurface->Lock(imageSurface, DSLF_WRITE, &display_buf, &display_buf_len));
   printf("dispUpdateScreen = %d/n", disp_num);
   if(!uiGetBuffer(display_buf))
   {
       DFBCHECK(imageSurface->Unlock(imageSurface));
       pthread_mutex_unlock(&mutex_display);
       return;
   }

   for(i=0; i<old_mouse_width; i++)
   {
       memcpy(mouse_bg_data+(i*MOUSE_WIDTH*BYTES_PER_PIXEL), display_buf+((old_mouse_y+i)*SCREEN_WIDTH+old_mouse_x)*BYTES_PER_PIXEL, old_mouse_width*BYTES_PER_PIXEL);
   }

   if(gbMouseShow)
   {
       old_mouse_width = MOUSE_WIDTH;
       old_mouse_height = MOUSE_HEIGHT;

       if(old_mouse_x+MOUSE_WIDTH>SCREEN_WIDTH)
       {
           old_mouse_width = SCREEN_WIDTH - old_mouse_x;
       }
       if(old_mouse_y+MOUSE_HEIGHT>SCREEN_HEIGHT)
       {
           old_mouse_height = SCREEN_HEIGHT - old_mouse_y;
       }
       for(i=0; i<old_mouse_height; i++)
       {
           unsigned char* pTmp = (unsigned char*)mouse_data + i*MOUSE_WIDTH*3;
           for(j=0; j<old_mouse_width; j++)
           {
               if(*pTmp != 0x00)
               {
                   *((UINT8*)display_buf+((old_mouse_y+i)*SCREEN_WIDTH+old_mouse_x+j)*BYTES_PER_PIXEL) = *pTmp;
                   *((UINT8*)display_buf+((old_mouse_y+i)*SCREEN_WIDTH+old_mouse_x+j)*BYTES_PER_PIXEL+1) = *pTmp;
                   *((UINT8*)display_buf+((old_mouse_y+i)*SCREEN_WIDTH+old_mouse_x+j)*BYTES_PER_PIXEL+2) = *pTmp;
               }
               pTmp+=3;
           }
       }
   }

   DFBCHECK(imageSurface->Unlock(imageSurface));
   primary->Blit (primary, imageSurface, &rect, 0, 0);
exit:
   pthread_mutex_unlock(&mutex_display);
   return;
}