video.cpp

DOS下利用VESA实现高分辨率、16bit色显示并输出汉字

    fread(pFontE, sizeof(char), 16, fpE);
    for(iy=0; iy<16; iy++)
    {
	for(ix=0; ix<8; ix++)
	{
	    if(*(pFontE+iy)&(1<<ix))
		SetPoint(x+8-ix, iy+y, iColor);
	}
    }
}

/****************************************************
Function:
    Draw an English string
Input parameter:
    x, y: start coordinate of character
    text: string that contains text
    iColor: specified color
Output parameter:
    None
****************************************************/
void DrawEnglishString(int x, int y, char *text, int iColor)
{
    int ix, iy;
    int i=0;
    ix=x;
    iy=y;
    while(*(text+i))
    {
	DrawEnglish(ix, iy, *(text+i), iColor);
	ix=ix+9;
	i++;
    }
}

/****************************************************
Function:
    Open Font to get information for DrawEnglish,
    must call this function before draw any text.
Input parameter:
    None
Output parameter:
    0: Error
    1: OK
****************************************************/
int OpenCFont()
{
    if(VIDDID(0, 11)!=0xc0102c)
	return 0;
    fpC=fopen("hzk16", "rb");
    if(fpC == NULL)
    {
	printf("Error opening asc16\n");
	printf("Press any key to exit...\n");
	getch();
	return 0;
    }
    pFontC = (unsigned char *)malloc(sizeof(char)*32);
    return 1;
}

/****************************************************
Function:
    Close Font, must call it before exit.
Input parameter:
    None
Output parameter:
    None
****************************************************/
void CloseCFont()
{
    fclose(fpC);
    free(pFontC);
}

/****************************************************
Function:
    Draw an English character
Input parameter:
    x, y: coordinate of character
    c1, c2: code of Chinese word
    iColor: specified color
Output parameter:
    None
****************************************************/
void DrawChinese(int x, int y, int c1, int c2, int iColor)
{
    int ix, iy;
    unsigned long int qu, wei;

    qu=c1-161;
    wei=c2-161;
    fseek(fpC, 32l*(94*qu+wei), SEEK_SET);
    //fseek(fpC, 0x1100l*32, SEEK_SET);
    fread(pFontC, 32, 1, fpC);
    for(iy=0; iy<16; iy++)
    {
	for(ix=0; ix<8; ix++)
	{
	    if(*(pFontC+iy*2)&(1<<ix))
		    SetPoint(x+8-ix, iy+y, iColor);
	    if(*(pFontC+iy*2+1)&(1<<ix))
		    SetPoint(x+16-ix, iy+y, iColor);
	}
    }
}

/****************************************************
Function:
    Draw an Chinese string
Input parameter:
    x, y: start coordinate of character
    text: string that contains text
    iColor: specified color
Output parameter:
    None
****************************************************/
void DrawChineseString(int x, int y, unsigned char *text, int iColor)
{
    int ix, iy;
    int i=0;
    int c1, c2;
    ix=x;
    iy=y;
    while(*(text+i))
    {
	if(((*(text+i))&0x80)!=0)     // Chinese Word.
	{
	    c1=*(text+i);
	    i++;
	    c2=*(text+i);
	    i++;
	    DrawChinese(ix, iy, c1, c2, iColor);
	    ix=ix+16;
	}
	else                          // English word
	{
	    c1=*(text+i);
	    i++;
	    DrawEnglish(ix, iy, c1, iColor);
	    ix=ix+8;
	}
    }
}

/////////////////////////////////////////////////////
//All following function added by the request of client
/////////////////////////////////////////////////////

/****************************************************
Function Name:
    GetPoint
Function:
    Get the color of specified point
Input parameter:
    x, y: coordinate
Output parameter:
    iColor: color of specified color
****************************************************/
unsigned int GetPoint(int x, int y)
{
    unsigned long iDist, iTemp;
    unsigned int iPos;
    unsigned int iColor;
    int iPN;
    iDist = 800l*y+x;
    iTemp = iDist;
    iPN = 0;
    while(iTemp>32768)
    {
	iTemp = iTemp - 32768;
	iPN++;
    }
    iPos = iTemp;
    if(iPN != iOldPage)
	VideoPage(iPN);
    iColor = *(pVideoMem+iPos);
    return iColor;
}

/****************************************************
Function Name: GetImageSize
Function:
    Get Size of Image needed, used to allocate memory
Input parameter:
    iStartX, iStartY: left-up coordinate of box
    iEndX, iEndY: right-bottom coordinate of box
Output parameter:
    iImageSize: image size in bytes
****************************************************/
int GetImageSize(int iStartX, int iStartY, int iEndX, int iEndY)
{
    return ((iEndX-iStartX)*(iEndY-iStartY)+2)*sizeof(int);
}

/****************************************************
Function Name: GetImage
Function:
    Get Image from video buffer, save for other using
    Be sure that iEndX>iStartX, and iEndY>iStartY!!!!!
Input parameter:
    iStartX, iStartY: left-up coordinate of box
    iEndX, iEndY: right-bottom coordinate of box
    int *Buffer: buffer to store image
Output parameter:
    None
****************************************************/
void GetImage(int iStartX, int iStartY, int iEndX, int iEndY, int far *Buffer)
{
    unsigned long iCurX, iCurY;
    int i=0;
    *(Buffer+i)=iEndX-iStartX;	//Store image width
    i++;
    *(Buffer+i)=iEndY-iStartY;	//Store image height
    i++;
    for(iCurY=iStartY; iCurY<iEndY; iCurY++)
    {
	for(iCurX=iStartX; iCurX<iEndX; iCurX++)
	{
	    *(Buffer+i)=GetPoint(iCurX, iCurY);
	    i++;
	}
    }
}

/****************************************************
Function Name: PutImage
Function:
    Put saved image to specified position
Input parameter:
    iStartX, iStartY: left-up coordinate of image
    int *Buffer: buffer to store image
Output parameter:
    None
****************************************************/
void PutImage(int iStartX, int iStartY, int far *Buffer)
{
    unsigned long iCurX, iCurY;
    int iEndX, iEndY;
    int iWidth, iHeight;
    int i=0;

    iWidth=*(Buffer+i);
    i++;
    iHeight=*(Buffer+i);
    i++;
    iEndX=iStartX+iWidth;
    iEndY=iStartY+iHeight;

    for(iCurY=iStartY; iCurY<iEndY; iCurY++)
    {
	for(iCurX=iStartX; iCurX<iEndX; iCurX++)
	{
	    SetPoint(iCurX, iCurY, *(Buffer+i));
	    i++;
	}
    }
}

/****************************************************
Function:
    Draw a point with specified color, XOR_OUTPUT
Input parameter:
    x, y: coordinate
    iColor: specified color
Output parameter:
    None
****************************************************/
void SetPointXOR(int x, int y, unsigned int iColor)
{
    unsigned long iDist, iTemp;
    unsigned int iPos;
    int iPN;
    unsigned int iOldColor;
    iDist = 800l*y+x;
    iTemp = iDist;
    iPN = 0;
    while(iTemp>32768)
    {
	iTemp = iTemp - 32768;
	iPN++;
    }
    iPos = iTemp;
    if(iPN != iOldPage)
	VideoPage(iPN);
    iOldColor=*(pVideoMem+iPos);
    iColor=iColor^iOldColor;
    *(pVideoMem+iPos) = iColor;
}

/****************************************************
Function:
    Draw a line with specified color, XOR
Input parameter:
    startx, starty: coordinate of start point
    endx, endy: coordinate of end point
    iColor: specified color
Output parameter:
    None
****************************************************/
void MemLineXOR(int startx, int starty, int endx, int endy, unsigned int color)
{
    register int t, distance;
    int xerr=0, yerr=0, delta_x, delta_y;
    int incx, incy;

    delta_x = endx-startx;
    delta_y = endy-starty;

    if(delta_x>0) incx = 1;
    else if (delta_x == 0 ) incx = 0;
    else incx = -1;

    //Compute the direcxtion of the increment,
    //an increment of 0 means either a vertical of horizontral line.
    if(delta_y>0) incy = 1;
    else if (delta_y == 0 ) incy = 0;
    else incy = -1;

    //Determine which distance is greater
    delta_x = abs(delta_x);
    delta_y = abs(delta_y);
    if(delta_x>delta_y) distance = delta_x;
    else distance = delta_y;

    //Draw the line
    for(t=0; t<=distance+1; t++)
    {
	SetPointXOR(startx, starty, color);
	xerr+=delta_x;
	yerr+=delta_y;
	if(xerr>distance)
	{
	    xerr-=distance;
	    startx+=incx;
	}
	if(yerr>distance)
	{
	    yerr-=distance;
	    starty+=incy;
	}
    }
}

/****************************************************
Function:
    32 bit inport
Input parameter:
    portnum: port number
Output parameter:
    32bit value
****************************************************/
static DWORD _inpd(int portnum)
{
    static DWORD value;
    asm mov dx, portnum;
    asm lea bx, value;
    #if defined(__BORLANDC__)
	__emit__(0x66, 0x50,		//push EAX
		 0x66, 0xED,		//in EAX, DX
		 0x66, 0x89, 0x07,	//mov [BX], EAX
		 0x66, 0x58);		//pop EAX
    #else
	asm push eax;
	asm in eax, dx;
	asm mov [bx], eax;
	asm pop eax;
    #endif
    return value;
}

/****************************************************
Function:
    32 bit outport
Input parameter:
    portnum: port number
    val: 32bit data to output
Output parameter:
    32bit value
****************************************************/
static DWORD _outpd(int portnum, DWORD val)
{
    static DWORD value=0;
    value = val;
    asm mov dx, portnum;
    asm lea bx, value;
    #if defined(__BORLANDC__)
	__emit__(0x66, 0x50,		//push EAX
		 0x66, 0x8B, 0X07,	//in EAX, [BX]
		 0x66, 0xEF,   		//out DX, EAX
		 0x66, 0x58);		//pop EAX
    #else
	asm push eax;
	asm mov eax, [bx];
	asm out dx, eax;
	asm pop eax;
    #endif
    return value;
}

/****************************************************
Function:
    Read Vendor ID & Device ID from specified space
Input parameter:
    iBus: Bus Number
    iDevice: Device Number
Output parameter:
    DeviceID & Vendor ID
****************************************************/
unsigned long VIDDID(int iBus, int iDevice)
{
    unsigned long iod;
    unsigned long iobase;
    iobase = 0x80000000+iBus*0x10000+(iDevice*8)*0x100;
    _outpd(0xcf8, iobase);
    iod=_inpd(0xcfc);
    return iod;
}