henesyinit from p9fd787fda5 years agoHistory
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#include <u.h>#include <libc.h>#include "map.h" static struct coord stdp0, stdp1;static double k; static intXlambert(struct place *place, double *x, double *y){	double r;	if(place->nlat.l < -80.*RAD)		return(-1);	if(place->nlat.l > 89.*RAD)		r = 0;	/* slovenly */	else		r = stdp0.c*exp(0.5*k*log(		   (1+stdp0.s)*(1-place->nlat.s)/((1-stdp0.s)*(1+place->nlat.s))));	if(stdp1.l<0.)		r = -r;	*x = - r*sin(k * place->wlon.l);	*y = - r*cos(k * place->wlon.l);	return(1);} projlambert(double par0, double par1){	double temp;	if(fabs(par0)>fabs(par1)){		temp = par0;		par0 = par1;		par1 = temp;	}	deg2rad(par0, &stdp0);	deg2rad(par1, &stdp1);	if(fabs(par1+par0)<.1) 		return(mercator());	if(fabs(par1-par0)<.1)		return(perspective(-1.));	if(fabs(par0)>89.5||fabs(par1)>89.5)		return(0);	k = 2*log(stdp1.c/stdp0.c)/log(		(1+stdp0.s)*(1-stdp1.s)/((1-stdp0.s)*(1+stdp1.s)));	return(Xlambert);}