system.mat

// Victor Ortiz 2009
function sistema
f=figure('Color','black');
load topo

axis square off
props.FaceColor= 'texture';
props.EdgeColor = 'none';
props.FaceLighting = 'phong';
props.Cdata = topo;

[tx,ty,tz] = sphere(13);
axis([-100,100,-100,100,-100,100]);
axis off vis3d

campos([-30,30,30])
hold on
surface(tx,ty,tz,'EdgeColor','red');        
tx = tx+5;
lx = (tx * 0.25);
ly = (ty * 0.25);
lz = (tz * 0.25);

z2 = tz;
for j=0:.1:(2*pi)
    x2 = (tx)*cos(j)-ty*sin(j);
    y2 = (tx)*sin(j)+ty*cos(j);    
    tierra = surface(x2+cos(j),y2+sin(j),z2,props);        
    for i=0:.1:(2*pi)    
        x1 = ((lx)*cos(i)-ly*sin(i));
        y1 = ((lx)*sin(i)+ly*cos(i));
        z1 = lz;    
        luna = surface(x1+cos(j)*6,y1+sin(j)*6,z1,'EdgeColor','white');                
        pause(0.001);
        delete(luna);        
    end        
    delete(tierra);
end
close(f)
end