C语言如何实现画图教程

C语言有丰富的数据结构和运算符。包含了各种数据结构，如整型、数组类型、指针类型和联合类型等，用来实现各种数据结构的运算。以下是小编为大家搜索整理的C语言如何实现画图教程，希望能给大家带来帮助!更多精彩内容请及时关注我们应届毕业生考试网!

程序中定义了几个特殊键：

"V”：画笔提起

"W”：开始画图

"R”：开始擦图

"S”：当前图形存入文件

"E”：调出已有文件

"C”：画圆

程序一运行，屏幕上出现一个黄色的边框来设定画图的.区域，区域中间出现提起的画笔符号 ，当按下”W“键时，画笔符号变为 ，此时可移动方向键(上、下、左、右、左上、左下、右上、右下)来画图;当按下”R“键时，画笔符号变为 ，此时可移动方向键来擦图;在画图过程中，按下“C”键，可画出一个半径为20个象素点的圆;当结束画图时，按下“S”键，将画好的图形存盘;按下“E”键可调出已有的图形进行编辑。

　　3.源程序清单

# include "graphics.h"

# include "stdio.h"

# include "fcntl.h"

# include "stdlib.h"

main()

void save(),load();

void *wg,*rg,*vg,*fy;

int driver,mode;

int c=RED;

int x=320,y=225;

int x1,y1,x2,y2;

int k,k1,k2;

/* initialize grapher */

detectgraph(&driver,&mode);

initgraph(&driver,&mode,"c:tc");

/* write the pen */

bar(200,10,206,16);

line(203,7,200,10);

line(203,7,206,10);

line(243,7,240,16);

line(243,7,246,16);

line(283,7,280,10);

line(283,7,286,10);

line(283,7,283,16);

/* save the pen */

wg=malloc(imagesize(200,7,206,16));

rg=malloc(imagesize(240,7,246,16));

vg=malloc(imagesize(280,7,286,16));

fy=malloc(imagesize(200,7,206,16));

getimage(200,7,206,16,wg);

getimage(240,7,246,16,rg);

getimage(280,7,286,16,vg);

cleardevice();

/* write the box */

setcolor(YELLOW);

rectangle(4,19,637,447);

x1=x-3;

y1=y+1;

x2=x+3;

y2=y+10;

getimage(x1,y1,x2,y2,fy);

putimage(x1,y1,vg,XOR_PUT);

/* receive the command */

for (;;)

while (bioskey(1)==0);

k=bioskey(0);

putimage(x1,y1,fy,AND_PUT);

if (((k&0x00ff)|0x00)==0)

k1=k&0xff?0:k>>8; /* k1 is the specialkey value */

else

k2=k&0x00ff; /* k2 is the non-specialkey value */

if (((k&0x00ff)|0x00)==0) /* Special key */

switch(k1)

case 45:

restorecrtmode();

exit(0);

case 72:

if (y>20)

y=y-1;

break;

case 75:

if (x>5)

x=x-1;

break;

case 77:

if (x<636)

x=x+1;

break;

case 80:

if (y<446)

y=y+1;

break;

case 71:

if ((x>5)&&(y>20))

x=x-1;

y=y-1;

break;

case 79:

if ((x>5)&&(y<446))

x=x-1;

y=y+1;

break;

case 73:

if ((x<636)&&(y>20))

x=x+1;

y=y-1;

break;

case 81:

if ((x<636)&&(y<446))

x=x+1;

y=y+1;

break;

x1=x-3;

y1=y+1;

x2=x+3;

y2=y+10;

getimage(x1,y1,x2,y2,fy);

/* non-special key */

switch(k2)

case 118: /* 'v' */

case 86: /* 'V' */

putimage(x1,y1,vg,OR_PUT);

break;

case 119: /* 'w' */

case 87: /* 'W' */

putimage(x1,y1,wg,OR_PUT);

putpixel(x,y,c);

break;

case 114: /* 'r' */

case 82: /* 'R' */

putimage(x1,y1,rg,OR_PUT);

putpixel(x,y,BLACK);

break;

case 115: /* 's' */

case 83: /* 'S' */

save("");

break;

case 101: /* 'e' */

case 69: /* 'E' */

load("");

break;

case 99: /*'c'*/

case 67: /*'C'*/

setcolor(RED);

circle(x,y,20);

break;

default:continue;

/* function for screen picture save

*/

void save(char *fname)

FILE *fp;

int i;

register long j;

char far *ptr;

fp=fopen(fname,"wb");

for(i=0;i<4;i++)

outportb(0x3CE,4);

outportb(0x3CF,i);

ptr=(char far *) 0xA0000000L;

for (j=0;j<38400L;j++)

putc(*ptr,fp);

ptr++;

fclose(fp);

outportb(0x3CF,0);

/* function for screen picture display

*/

void load(char *fname)

FILE *fp;

register int i;

int k4=1;

register long j;

char far *ptr;

fp=fopen(fname,"rb");

for (i=0;i<4;i++)

outportb(0x3C4,2);

outportb(0x3C5,k4);

ptr=(char far *)0xA0000000L;

for (j=0;j<38400L;j++)

*ptr=getc(fp);

ptr++;

k4*=2;

fclose(fp);

outportb(0x3C5,0xF);

　　4.结束语

该程序在Turbo C 2.0环境下运行通过，使用效果良好。可以根据具体需要，对该程序进行扩充，以增加绘图功能。