[转]C语言gd库画图bng

gdImagePtr im;
int back,border,blue;
int xsize,ysize;
char str[5];
int size;
char* ptr;

xsize = 60;
ysize = 20;
sprintf(str,"%04d",1234);

im = gdImageCreate(xsize,ysize);
back = gdImageColorAllocate(im,255,255,255);
border = gdImageColorAllocate(im, 0,0,0);
blue = gdImageColorAllocate(im,30,130,211);
gdImageFilledRectangle(im,0,0,xsize - 1,ysize - 1,back);
gdImageRectangle(im,0,0,xsize - 1,ysize - 1,border);
gdImageString(im, gdFontGetLarge(),
              im->sx / 2 - (strlen(str) * gdFontGetLarge()->w / 2),
              im->sy / 2 - gdFontGetLarge()->h / 2,
              (unsigned char*)str, blue);

//print html HEAD
printf("Content-type: image/png\n\n");

//write content
ptr = gdImagePngPtr(im, &size);
fwrite(ptr,size,1,stdout);
gdFree(ptr);

/* Destroy it */
gdImageDestroy(im);