From db9351f8d2a3b4910858cf23367cafe5a39ff3eb Mon Sep 17 00:00:00 2001 From: tomsmeding Date: Wed, 5 Apr 2017 22:42:56 +0200 Subject: Plot arg as hue, norm as value --- attract.c | 29 +++++++++++++++++++++++------ 1 file changed, 23 insertions(+), 6 deletions(-) diff --git a/attract.c b/attract.c index c4cba5c..5ab9aa7 100644 --- a/attract.c +++ b/attract.c @@ -19,6 +19,9 @@ const double EPS=1e-1; static double complex att_func(double complex x,double exponent){ return clog((1-cpow(x,exponent+1))/(1-x)); + // return x; + return x*x+CMPLX(-0.2,0.7); + // return csqrt(M_SQRT2*x); // sqrt(2) and 0 // return csqrt(1+x); // phi // return csqrt(2*x-1); // attracts REALLY SLOWLY to 1+0i @@ -26,20 +29,34 @@ static double complex att_func(double complex x,double exponent){ // return clog(x*x); // "241" basins // return clog(x*x+x); // 3 basins but intricate structure // return clog(x*x*x*x+x*x*x+x*x+x+1); // 2 basin fractal? - // return csqrt(x*x*x+x*x+x+1); + // return csqrt(x*x*x+x*x+x+1); // lots of nans but really interesting lines } struct colour{ unsigned char r,g,b; }; +static struct colour from_hue(double H){ // H in [0,1] + const int C=255; + double Hmod=H>=2.0/3 ? H-2.0/3 : H>=1.0/3 ? H-1.0/3 : H; + int X=C*(1-fabs(Hmod*6-1)); + if(H<=1.0/6)return (struct colour){C,X,0}; + if(H<=2.0/6)return (struct colour){X,C,0}; + if(H<=3.0/6)return (struct colour){0,C,X}; + if(H<=4.0/6)return (struct colour){0,X,C}; + if(H<=5.0/6)return (struct colour){X,0,C}; + return (struct colour){C,0,X}; +} + static struct colour make_colour(double complex z){ static const double N=3; double norm=cabs(z); if(norm>N)norm=N; - int normclr=(int)(norm/N*255); - int argclr=(int)((carg(z)+M_PI)/(2*M_PI)*255); - return (struct colour){normclr,argclr,0}; + struct colour clr=from_hue((carg(z)+M_PI)/(2*M_PI)); + clr.r*=norm/N; + clr.g*=norm/N; + clr.b*=norm/N; + return clr; } struct config{ @@ -115,8 +132,8 @@ static void* thread_entry(void *arg_vp){ } int main(int argc,char **argv){ - const double minx=-3,miny=-3; - const double maxx=3,maxy=3; + const double minx=-1.5,miny=-1.5; + const double maxx=1.5,maxy=1.5; const double width=1000; struct config cfg={ -- cgit v1.2.3-70-g09d2