用c语言画ppm图片（二）

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1. PPM介绍

关于PPM的介绍请看用c语言画ppm图片（一）这篇文章

这篇文章中的代码我也没有都运行过，可能有差错，仅供参考。

2. 主代码

#include 
#include 
#include 
#define DIM 1024
#define DM1 (DIM-1)
#define _sq(x) ((x)*(x)) // square
#define _cb(x) abs((x)*(x)*(x)) // absolute value of cube
#define _cr(x) (unsigned char)(pow((x),1.0/3.0)) // cube root
 
unsigned char GR(int,int);
unsigned char BL(int,int);
 
unsigned char RD(int i,int j){
   // YOUR CODE HERE
}
unsigned char GR(int i,int j){
   // YOUR CODE HERE
}
unsigned char BL(int i,int j){
   // YOUR CODE HERE
}
 
void pixel_write(int,int);
FILE *fp;
int main(){
    fp = fopen("MathPic.ppm","wb");
    fprintf(fp, "P6\n%d %d\n255\n", DIM, DIM);
    for(int j=0;j

3. 欣赏

unsigned char RD(int i,int j){
    return (char)(_sq(cos(atan2(j-512,i-512)/2))*255);
}
 
unsigned char GR(int i,int j){
    return (char)(_sq(cos(atan2(j-512,i-512)/2-2*acos(-1)/3))*255);
}
 
unsigned char BL(int i,int j){
    return (char)(_sq(cos(atan2(j-512,i-512)/2+2*acos(-1)/3))*255);
}

4. 欣赏

unsigned char RD(int i,int j){
    #define r(n)(rand()%n)
    static char c[1024][1024];return!c[i][j]?c[i][j]=!r(999)?r(256):RD((i+r(2))%1024,(j+r(2))%1024):c[i][j];
}
 
unsigned char GR(int i,int j){
    static char c[1024][1024];return!c[i][j]?c[i][j]=!r(999)?r(256):GR((i+r(2))%1024,(j+r(2))%1024):c[i][j];
}
 
unsigned char BL(int i,int j){
    static char c[1024][1024];return!c[i][j]?c[i][j]=!r(999)?r(256):BL((i+r(2))%1024,(j+r(2))%1024):c[i][j];
}

5. 欣赏

unsigned char RD(int i,int j){
    float x=0,y=0;int k;for(k=0;k++<256;){float a=x*x-y*y+(i-768.0)/512;y=2*x*y+(j-512.0)/512;x=a;if(x*x+y*y>4)break;}return log(k)*47;
}
 
unsigned char GR(int i,int j){
    float x=0,y=0;int k;for(k=0;k++<256;){float a=x*x-y*y+(i-768.0)/512;y=2*x*y+(j-512.0)/512;x=a;if(x*x+y*y>4)break;}return log(k)*47;
}
 
unsigned char BL(int i,int j){
    float x=0,y=0;int k;for(k=0;k++<256;){float a=x*x-y*y+(i-768.0)/512;y=2*x*y+(j-512.0)/512;x=a;if(x*x+y*y>4)break;}return 128-log(k)*23;
}

6. 欣赏

unsigned char RD(int i,int j){
    double a=0,b=0,c,d,n=0;
    while((c=a*a)+(d=b*b)<4&&n++<880)
    {b=2*a*b+j*8e-9-.645411;a=c-d+i*8e-9+.356888;}
    return 255*pow((n-80)/800,3.);
}
 
unsigned char GR(int i,int j){
    double a=0,b=0,c,d,n=0;
    while((c=a*a)+(d=b*b)<4&&n++<880)
    {b=2*a*b+j*8e-9-.645411;a=c-d+i*8e-9+.356888;}
    return 255*pow((n-80)/800,.7);
}

unsigned char BL(int i,int j){
    double a=0,b=0,c,d,n=0;
    while((c=a*a)+(d=b*b)<4&&n++<880)
    {b=2*a*b+j*8e-9-.645411;a=c-d+i*8e-9+.356888;}
    return 255*pow((n-80)/800,.5);
}

7. 欣赏

unsigned char RD(int i,int j){
    static double k;k+=rand()/1./RAND_MAX;int l=k;l%=512;return l>255?511-l:l;
}
 
unsigned char GR(int i,int j){
    static double k;k+=rand()/1./RAND_MAX;int l=k;l%=512;return l>255?511-l:l;
}
 
unsigned char BL(int i,int j){
    static double k;k+=rand()/1./RAND_MAX;int l=k;l%=512;return l>255?511-l:l;
}

8. 欣赏

unsigned char RD(int i,int j){
    float s=3./(j+99);
    float y=(j+sin((i*i+_sq(j-700)*5)/100./DIM)*35)*s;
    return (int((i+DIM)*s+y)%2+int((DIM*2-i)*s+y)%2)*127;
}
 
unsigned char GR(int i,int j){
    float s=3./(j+99);
    float y=(j+sin((i*i+_sq(j-700)*5)/100./DIM)*35)*s;
    return (int(5*((i+DIM)*s+y))%2+int(5*((DIM*2-i)*s+y))%2)*127;
}
 
unsigned char BL(int i,int j){
    float s=3./(j+99);
    float y=(j+sin((i*i+_sq(j-700)*5)/100./DIM)*35)*s;
    return (int(29*((i+DIM)*s+y))%2+int(29*((DIM*2-i)*s+y))%2)*127;
}

9. 欣赏

unsigned char RD(int i,int j){
    #define D DIM
    #define M m[(x+D+(d==0)-(d==2))%D][(y+D+(d==1)-(d==3))%D]
    #define R rand()%D
    #define B m[x][y]
    return(i+j)?256-(BL(i,j))/2:0;
}
 
unsigned char GR(int i,int j){
    #define A static int m[D][D],e,x,y,d,c[4],f,n;if(i+j<1){for(d=D*D;d;d--){m[d%D][d/D]=d%6?0:rand()%2000?1:255;}for(n=1
    return RD(i,j);
}
 
unsigned char BL(int i,int j){
    A;n;n++){x=R;y=R;if(B==1){f=1;for(d=0;d<4;d++){c[d]=M;f=f2){B=f-1;}else{++e%=4;d=e;if(!c[e]){B=0;M=1;}}}}}return m[i][j];
}

10. 欣赏

unsigned char RD(int i,int j){
    #define A float a=0,b,k,r,x
    #define B int e,o
    #define C(x) x>255?255:x
    #define R return
    #define D DIM
    R BL(i,j)*(D-i)/D;
}
 
unsigned char GR(int i,int j){
    #define E DM1
    #define F static float
    #define G for(
    #define H r=a*1.6/D+2.4;x=1.0001*b/D
    R BL(i,j)*(D-j/2)/D;
}
 
unsigned char BL(int i,int j){
    F c[D][D];if(i+j<1){A;B;G;aD/2){e=a;o=(E*x);c[e][o]+=0.01;}}}}}R C(c[j][i])*i/D;
}