// ----------------------------------------
// To see the real isosurface:
// #declare approximateISO = no;

// To produce a smooth_triangle approximation:
// #declare approximateISO = yes; #declare isoSmooth = yes; 

// To produce a flat triangle approximation:
// #declare approximateISO = yes; #declare isoSmooth = no; 

// ----------------------------------------

#include "functions.inc" 

/*
//#declare Fn = function { f_torus(x, y, z, 1, 0.4) }
//#declare Fn = function { y - sin(2*x*z)*cos(x*z) }
#declare Fn = function { cos(2*pi*x) + cos(2*pi*y) + cos(2*pi*z) }
#declare isoThreshold = 0.0;
#declare R = 2.0;
#declare isoMin = -<1, 1, 1>*R;
#declare isoMax = +<1, 1, 1>*R;
*/

#declare Scene_scale	= 1;
#declare R = Scene_scale * 2;
#declare Blob_radius	= 2*Scene_scale;
#declare Blob_distance	= 1*Scene_scale;
#declare Blob_threshold_1 = 3;
#declare Blob_threshold_2 = 3;
#declare Blob_boxsize   = <1,1,1,> * R;
//#declare fn_A = function { Blob_radius / sqrt(pow(x+Blob_distance,2) + pow(y,2) + pow(z,2)) };
//#declare fn_B = function { Blob_radius / sqrt(pow(x-Blob_distance,2) + pow(y,2) + pow(z,2)) };
//#declare fn_C = function { Blob_threshold_1 };
//#declare fn_D = function { fn_A(x,y,z) + fn_B(x,y,z) - fn_C(x,y,z) };
//#declare fn_E_1 = function { -1 * min(Blob_threshold_2, max(0, fn_D(x,y,z))) };
#declare fn_E_2 = function { -1 * min(Blob_threshold_2, max(0, Blob_radius / sqrt(pow(x+Blob_distance,2) + pow(y,2) + pow(z,2)) + Blob_radius / sqrt(pow(x-Blob_distance,2) + pow(y,2) + pow(z,2)) - Blob_threshold_1)) };
#declare Fn = function { fn_E_2(x,y,z) }
#declare isoMin = -Blob_boxsize;
#declare isoMax = +Blob_boxsize;


// Set to yes to produce the approximation or to no for actual isosurface
#declare approximateIso = yes;

#if (approximateIso)
//	#declare Depth = 1; // Set to 0 for no recursion
//	#declare isoSmooth = yes;
//	#declare isoSegs = <1, 1, 1>*6;
	#declare isoFileOption = 1;
	#declare isoFile = "triangles.inc";
	#declare isoName = "Surface";
//	#include "isosurface_kl_jf_tok.inc"
//	#include "isosurf_kl_jf.inc"
	#include "isosurfacejf9.inc"
//	#include "isosurface.inc"
	object {
		Surface
		pigment { color rgb <1, 1, 1>*0.9 }
		finish {
			phong 0.5
			phong_size 10
		}
	}
#else
	isosurface {
		function { Fn(x, y, z) }
		max_gradient 8.0
		contained_by { box { isoMin, isoMax } }
		open
		pigment { color rgb <1, 1, 1>*0.9 }
		finish {
			phong 0.5
			phong_size 10
		}
	}
#end // if

// ----------------------------------------

sky_sphere {
	pigment {
		function { abs(y) }
		color_map {
			[ 0.0 color rgb <0.0, 0.0, 0.6> ]
			[ 1.0 color rgb <1.0, 1.0, 1.0> ]
		}
	}
}

camera {
	location <1, 2, -4>*2*R
	look_at <0, 0, 0>
	angle 32
}

light_source {
	<1, 2, -1>*100
	color rgb <1, 1, 1>
	shadowless
}

light_source {
	<-1, -2, -1>*100
	color rgb <1, 1, 1>*0.5
	shadowless
}

// ----------------------------------------