数据压缩LZW算法源代码

#include "graph.h" #include "math.h" #include "stdio.h" double pi=3.14159; double n=36.0; static double xx[]={150.0,200.0,210.0,60.0,150.0}; static double zz[]={0.0,0.0,0.0,0.0,0.0}; static double xy[]={-55.0,-20.0,50.0,40.0,-55.0}; static double f[4][4]; int i; double th; double x,y,z; double x0,y0,z0; void affine(void); void affine3(double *x,double *y,double *z); void rotate_y(double theta_y); void axis(void); void main(void) { int graphdriver=DETECT,graphmode; initgraph(&graphdriver,&graphmode,""); cleardevice(); setactivepage(0); setvisualpage(0); setbkcolor(1); axis(); th=pi/n; rotate_y(th); affine(); getch(); closegraph(); } void axis(void) { line(320,240,600,240); line(320,240,320,100); } void rotate_y(double theta_y) { double co=cos(theta_y),si=sin(theta_y); f[0][0]=co;f[0][1]=si; f[0][3]=0.0; f[1][0]=0.0;f[1][1]=1.0; f[1][2]=0.0;f[1][3]=0.0; f[2][0]=-si;f[2][1]=0.0; f[2][2]=co;f[2][3]=0.0; f[3][0]=0.0;f[3][1]=0.0; f[3][2]=0.0;f[3][3]=1.0; } void affine3(double *x,*y,*z) { double _x,_y,_z; _x=*x;_y=*y;_z=*z; *x=_x*f[0][0]+_y*f[1][0]+_z*f[2][0]+f[3][0]; *y=_x*f[0][1]+_y*f[1][1]+_z*f[2][1]+f[3][1]; *z=_x*f[0][2]+_y*f[1][2]+_z*f[2][2]+f[3][2]; } void affine(void) { for(th=0.0;th<2*pi;th+=pi/n){ for(i=0;i<4;i++){ x=xx[i];y=yy[i];z=zz[i]; affine3(&x,&y,&z); if(i==0) putpixel(320+(int)x,240-(int)y,1); else{ setcolor(5); line(320+(int)x0,240-(int)y0,320+(int)x,240-(int)y); } xx[i]=x0=x;yy[i]=y0=y;zz[i]=z0=z; } } }