www.pudn.com > uCGUI3.24-MemDev-for-3.90a.rar > GUIDEV_Banding.c

/*! @file GUIDEV_Banding.c 
 *  Implementation of banding memory devices  
 * 
 *  @author hiber modified 
 *  @author Copyleft (C) 1981-2006, All Rights Givenup 
 *  @date 04/18/2006 
 *  @version  
 * 
 *  @note This routine uses a banding memory device to draw the given area flicker free.  
 *        It not only draws, but also automatically calculates the size of, creates, moves 
 *        and then destroys the memory device. 
 *  @attention  
 *  @warning  
 *  @bug 
 * 
 *  @todo 
 *  @example  
 *  @see 
 */ 
#include  
#include "GUI_Protected.h" 
#include "GUIDebug.h" 
 
#if GUI_SUPPORT_MEMDEV 
 
extern void * _GUI_ALLOC_h2p_Lock(GUI_HMEM hMem); 
#define GUI_ALLOC_H2P(h)          _GUI_ALLOC_h2p_Lock(h) 
#define GUI_ALLOC_FREE(handle)    GUI_ALLOC_Free(handle) 
#define GUI_ALLOC_LOCK(handle)    _GUI_ALLOC_h2p_Lock(handle) 
#define GUI_ALLOC_UNLOCK(handle) 
 
#ifdef GUI_USAGE_H2P 
    #undef GUI_USAGE_H2P 
    #define GUI_USAGE_H2P(h) ((GUI_USAGE*)_GUI_ALLOC_h2p_Lock(h))  
#endif 
 
#ifdef GUI_MEMDEV_H2P 
    #undef GUI_MEMDEV_H2P 
    #define GUI_MEMDEV_H2P _GUI_ALLOC_h2p_Lock 
#endif 
 
////////////////////////////////////////////////////////////////////////// 
 
static int Min(int v0, int v1) 
{ 
    if (v0 <= v1) 
    { 
        return v0; 
    } 
 
    return v1; 
} 
 
//! 防止显示屏闪烁的基本函数 
//! @param pRect 所使用的LCD 的一个GUI_RECT 结构的指针。 
//! @param pfDraw 执行绘图操作的一个回调函数的指针。 
//! @param pData 作为回调函数参数使用的一个数据结构的指针。 
//! @param NumLines 0（推荐）或者是存储设备的分段数量。 
//! @param Flags 0 或者 GUI_MEMDEV_HASTRANS。 
//! @return 如果成功返回0，如果函数执行失败则返回1。 
//! @note 如果参数NumLines 为0，则每段中的线段数量由函数自动计算。通过移动存储设备的原 
//!       点，函数一段又一段地重复改写输出区域。 
int GUI_MEMDEV_Draw(GUI_RECT *pRect, GUI_CALLBACK_VOID_P *pfDraw,  
                    void *pData, int NumLines, int Flags) 
{ 
    int x0, y0, x1, y1, xsize, ysize; 
    GUI_MEMDEV_Handle hMD; 
 
    if (pRect) 
    { 
        x0 = (pRect->x0 < 0) ? 0 : pRect->x0; 
        y0 = (pRect->y0 < 0) ? 0 : pRect->y0; 
 
        x1 = Min(pRect->x1, LCD_GET_XSIZE() - 1); 
        y1 = Min(pRect->y1, LCD_GET_YSIZE() - 1); 
 
        xsize = x1 - x0 + 1; 
        ysize = y1 - y0 + 1; 
    } 
    else 
    { 
        x0 = 0; 
        y0 = 0; 
 
        xsize = LCD_GET_XSIZE(); 
        ysize = LCD_GET_YSIZE(); 
    } 
 
    if (NumLines == 0) 
    { 
        NumLines =  - ysize; /* Request  lines ... Less is o.k. */ 
    } 
 
    if ((xsize <= 0) || (ysize <= 0)) 
    { 
        return 0; 
    } 
 
     /* Nothing to do ... */ 
    /* Create memory device */ 
    hMD = GUI_MEMDEV_CreateEx(x0, y0, xsize, NumLines, Flags); 
    if (!hMD) 
    { 
        GUI_DEBUG_ERROROUT("GUI_MEMDEV_Draw() Not enough memory ..."); /* Not enough memory ! */ 
        pfDraw(pData); 
        return 1; 
    } 
 
    NumLines = GUI_MEMDEV_GetYSize(hMD); 
    GUI_MEMDEV_Select(hMD); 
 
    /* Start drawing ... */ 
    { 
        int i; 
        for (i = 0; i < ysize; i += NumLines) 
        { 
            int RemLines = ysize - i; 
 
            if (RemLines < NumLines) 
            { 
                GUI_MEMDEV_ReduceYSize(hMD, RemLines); 
            } 
 
            if (i) 
            { 
                GUI_MEMDEV_SetOrg(hMD, x0, y0 + i); 
                GUI_MEMDEV_Clear(hMD); 
            } 
 
            pfDraw(pData); 
            GUI_MEMDEV_CopyToLCD(hMD); 
        } 
    } 
 
    GUI_MEMDEV_Delete(hMD); 
    GUI_MEMDEV_Select(0); 
    return 0; /* Success ! */ 
} 
 
#else 
 
void GUIDEV_Banding(void) {} /* avoid empty object files */ 
 
#endif /* GUI_MEMDEV_SUPPORT */