S1: preparing for a photo 85x85pixels;
S2: transfer to coding:
jsfiddle.net/jarvis_chan/v17rtjtk/
Copy the coding
S3: OpenSCAD(recommended to use "devlopment snapshots开发版）, open atth, past image code in image var arr=();
S4:>>> save as STL
Code of atth mentioned in S3:
arr=;(where to put picture coding)
r=70; sphere 1/2diameter
hd=1.2; sphere thickness
height=85；
width=85;
hj=4;横竖像点间距
wj=4;
zoom=2.5; 可以改小一点，假如出现孔连
difference(){
difference(){
translate([0,0,r])sphere(r);
translate([0,0,r])sphere(r-2*hd);
translate([0,0,-0.7*r])cube(2*r,true);
}
for(h=[0:1:height]){
for(w=[0:1:width]{
if(arr[h*height+w].0.1{
hull(){
translate([(height/2-w)*wj,(height/2-h)*hj,2*r])
cube(arr[h*height+w]*zoom,,true);
cube(0.001,true);
}}}}}