program molecule;

var
	a: array[0..30, 0..30, 0..30] of boolean;
	x, y, z, i: integer;
	t: boolean;
	f: text;

procedure writeheader;
	begin
		writeln(f, 'object {');
		writeln(f, '  union {');
	end;

procedure writefooter;
	begin
		writeln(f, '  }');
		writeln(f, '  pigment { color green 1}');
		writeln(f, '  translate <-15, -15, -15>');
		writeln(f, '  scale <0.2, 0.2, 0.2>');
		writeln(f, '}');
	end;

procedure writepiece (a, b, c: real);
	begin
		writeln(f, '    sphere { <', a, ', ', b, ', ', c, '> .2 }');
		write('.');		{progress on text window}
	end;


function vertices (x, y, z: integer): boolean;
	begin
		if a[x, y, z] = true then
			vertices := false
		else if a[x + 1, y + 1, z + 1] or a[x + 1, y + 1, z - 1] or a[x + 1, y - 1, z + 1] or a[x + 1, y - 1, z - 1] or a[x - 1, y + 1, z + 1] or a[x - 1, y + 1, z - 1] or a[x - 1, y - 1, z + 1] or a[x - 1, y - 1, z - 1] then
			vertices := true
		else
			vertices := false;
	end;

procedure molecule;
	var
		x, y, z, i: integer;
	begin
		for x := 0 to 30 do
			for y := 0 to 30 do
				for z := 0 to 30 do
					a[x, y, z] := false;

		a[15, 15, 15] := true;
		writepiece(15, 15, 15);
		i := 0;
		repeat
			i := i + 1;
			repeat
				x := abs(random mod 29) + 1;
				y := abs(random mod 29) + 1;
				z := abs(random mod 29) + 1;
			until vertices(x, y, z);
			a[x, y, z] := true;
			writepiece(x, y, z);
		until i > 300;
	end;


begin
	showtext;
	rewrite(f, 'molecule.inc');
	writeheader;
	molecule;
	writefooter;
	close(f);
end.