怎么实现图片的旋转,谢谢
我想实现一个小图片的旋转(一个箭头旋转),请问,应该怎么用C语言实现.
假如图片存在pic[][]数组里面,怎么写代码呢
假如有现成的源代码,万分感激
没有代码的话,请说说思想,其他语言的代码也行.
谢谢
[解决办法]
抄了个：
/* CONVOLVE.C - Turbo C 2.0 implementation of image convolution */
/* ---------- by Wesley G. Faler. All code is "as is ". There */
/* is NO copyright. Use this code as you will, and if you make */
/* money at it, good for you. */
/*****************************************************************/
#include <slib.h>
#include <sio.h>
#include <graphics.h>
#include <alloc.h>
#include <ctype.h>
int load_cut(char *fname);
int load_convolution_maix(char *fname);
int convolve_image(void);
int swap_pictures(void);
int minx,maxx,miny,maxy;
int LOADPAGE=0;
int ENHANCEPAGE=1;
int *cmat, *pmat, *vmat;
int cmx,cmy,cmnum;
suct palettetype palette,newpal;
int driver,mode;
int cleancut=-1;
int init_graphics(void)
{
driver=DETECT; mode=0;
detectgraph(&driver,&mode);
if(driver==VGA) mode=VGAMED;
initgraph(&driver,&mode, " ");
getpalette(&palette);
getpalette(&newpal);
}
int cleanup_image(void)
{
int i,j,num,x,y,k;
if(cleancut <0) return;
setactivepage(LOADPAGE);
setvisualpage(ENHANCEPAGE);
for(x=minx;x <maxx;x ) {
for(y=miny;y <maxy;y ) {
if(getpixel(x,y)!=0) num=-1;
else num=0;
for(j=-1;j <2;j ) {
for(i=-1;i <2;i ) {
if(getpixel(x i,y j)!=0) num ;
}
}
if(num> cleancut) {
k=getpixel(x,y);
setactivepage(ENHANCEPAGE);
putpixel(x,y,k);
setactivepage(LOADPAGE);
}
}
}
k=ENHANCEPAGE; ENHANCEPAGE=LOADPAGE; LOADPAGE=k;
}
void show_test_image(void)
{
int i;
minx=cmx; miny=cmy;
maxx=100 minx; maxy=100 miny;
setcolor(1);
moveto(minx,miny);
randomize();
for(i=0;i <20;i )
lineto(random(100) minx,random(100) miny);
for(i=0;i <10;i )
fillellipse(random(50) 25 minx,random(50) 25 miny,random(25),random(25));
}
main()
{
char fname[50];
int flag=0;
load_convolution_maix( "maix.dat ");
printf( ".CUT file (1) or test image (0)? ");
scanf( "%d ",&flag);
flag= flag? 1:0;
if(flag) {
fflush(sin);
printf( "filename to process: ");
gets(fname);
}
printf( "Delete pixels with x or fewer neighbors. x= ");
scanf( "%d ",&cleancut);
if(cleancut> 8) cleancut=8;
init_graphics();
setactivepage(1); cleardevice();
setactivepage(0); cleardevice();
setactivepage(LOADPAGE); setvisualpage(LOADPAGE);
if(flag) load_cut(fname);
else show_test_image();
cleanup_image();
setvisualpage(ENHANCEPAGE);
convolve_image();
swap_pictures();
restorecrtmode();
}
int toggle_colors(char c)
{
c=tolower(c);
c=c- 'a ';
if(c <0 || c> =palette.size) return 0;
newpal.colors[c]= palette.colors[c]-newpal.colors[c];
setpalette(c,newpal.colors[c]);
return 1;
}
int swap_pictures(void)
{
int mode=0;
char a;
setvisualpage(LOADPAGE);
for(;;) {
a=getch();
if(a==27) return;
if(toggle_colors(a)) continue;
if(mode==0) setvisualpage(ENHANCEPAGE);
if(mode==1) setvisualpage(LOADPAGE);
mode=1-mode;
}
}
int convolve_image(void)
{
int i,j,k,nval;
int *vx, *vy, *c;
int colmax,offset,end,midy;
char **lines=NULL;
char *temp=NULL;
offset=-minx (cmx/2);
end=cmy-1; midy=cmy/2;
lines=(char **)malloc(cmy*sizeof(char *));
for(i=0;i <cmy;i ) lines[i]=(char *)malloc(sizeof(char)*(maxx-minx cmx 1));
setactivepage(LOADPAGE);
for(j=-cmy/2;j <cmy/2;j ) {
for(i=minx-cmx/2;i <(maxx cmx/2 1);i ) {
lines[j midy][i offset]=getpixel(i,j miny);
}
}
colmax=getmaxcolor();
for(j=miny;j <maxy;j ) {
setactivepage(LOADPAGE);
for(i=j cmy/2,k=minx-cmx/2,nval=maxx cmx/2;k <nval;k )
lines[end][k offset]=getpixel(k,i);
for(i=minx;i <maxx;i ) {
/* Load & multiply neighbors into maix */
setactivepage(LOADPAGE);
vx=vmat; vy=vmat 1; c=cmat; nval=0;
for(k=0;k <cmnum;k ) {
if(*c) nval = lines[(*vy) midy][i (*vx) offset]*(*c);
/* if(*c) nval = getpixel(i (*vx),j (*vy)) * (*c); */
c ;
vx =2; vy =2;
}
/* Cut off values too high or too low */
if(nval <0) nval=0;
if(nval> colmax) nval=colmax;
/* Place new pixel value */
setactivepage(ENHANCEPAGE);
putpixel(i,j,nval);
}
if(kbhit()) { getch(); break; }
/* rotate line pointers */
temp=lines[0];
for(i=1;i <cmy;i ) lines[i-1]=lines[i];
lines[end]=temp;
}
for(i=0;i <cmy;i ) {
if(lines[i]!=NULL) free(lines[i]);
}
if(lines!=NULL) {
free(lines);
}
return;
}
int build_offset_vectors(void)
