void BmpOrder(void)
{   
    T_Message RecvMsg;
    INT32U      color1 = 0xff00ff00, i, j;
    INT32U      color2 = 0x900000ff, color3=0xff001800, *pImgpixel, *pImgGhost,*pMenuP,*pMenuG;
    INT32       inc=1;
    float        alpha;
    OSD_RECT    rect,rect2;

    pImgpixel = (INT32U*)DTOS_DRV_AllocateMemory(160*500*sizeof(INT32U)); //定义一个160×500的内存 用于存储菜单栏的像素
    pImgGhost = (INT32U*)DTOS_DRV_AllocateMemory(160*500*sizeof(INT32U));
    pMenuP = (INT32U*)DTOS_DRV_AllocateMemory(200*280*sizeof(INT32U)); //用于子菜单标志的显示
    pMenuG = (INT32U*)DTOS_DRV_AllocateMemory(200*280*sizeof(INT32U));

    GFMReadRectangle(20,120, 160, 500,(INT8U*)pImgpixel);  //读取第一个菜单栏标记的像素

    alpha        = ((color2&0xff000000)>>24)/(float)256.0; //混合版  用于显示菜单标记的特殊显示
    rect.x        = 0;        //菜单栏操作的矩形框
    rect.y        = 0;
    rect.width    = 160;
    rect.height    = 500;

    rect2.x=0;        //子菜单操作的矩形框
    rect2.y=0;
    rect2.width=200;
    rect2.height=280;
   
    while(1)
    {
        
        memcpy(pImgGhost, pImgpixel, 160*500*sizeof(INT32U));  //将子菜单的像素数据copy到pImgGost中
        index=0;                                                //用于菜单标记的特殊色显示
        for(i=0;i<45;i++)//混合标记区域 X为区域控制变量  
        {
            for(j=0;j<160;j++)
            {
                pImgGhost[i*160+x+j] = mixColor(pImgpixel[i*160+x+j], color2, alpha);
                index++;
            }            
        }

        GFMWriteRectangle(20,120,rect,(INT8U*)pImgGhost,160,500);        //重绘菜单区域

        DTOS_DRV_ReceiveMessage( Test_queueID, &RecvMsg);  //接受用户消息   用于用户的操作
        switch(RecvMsg.param0)
        {
            case MSG_KeyUP:  //up键按下
            {
                mark=1;
                if(count>(page-1)*9) //count 为图片索引
                {            //当count大于0时 每按下一次 索引减1
                    count--;
                }
                else        //当count=0时直接将索引号变成最后一位
                {
                    count=page*9;
                }
                if(x>0)        //x变量用与菜单标记区域的控制  实现菜单栏的动态显示
                {
                    nbmp--;
                   x-=7200;
                }
                else
                {
                    nbmp=9;
                    x=64800;
                }
                break;
            }
            case MSG_KeyDOWN:  //down键按下
            {
                mark=1;
                if(count<page*9) //count 为图片索引
                {            //当count大于0时 每按下一次 索引减1
                    count++;
                }
                else        //当count=0时直接将索引号变成最后一位
                {
                    count=(page-1)*9;
                }  
                if(x<=64000)
                {
                    nbmp++;
                    x+=7200;
                }
                else
                {
                    nbmp=1;
                    x=0;
                }   
                break;
            }



这个是其中的一部分代码   提示出现这个错误：warning C4013: 'mixColor' undefined; assuming extern returning int


不知道这个什么意思  是mixColor没有申明吗？？

小弟初学   望指教

没法实现键盘方向键的控制  头疼啊