heard of 3d printing gun ??

actually 5 years ago when i was in school iwas unaware of more os technologies but i remember then i visited tech fest fin IIT bombay ! there i saw a technology that really view 3d prointing through a gun the gun would convert the things into 3d object all we need to do was rto draw things in air and the molten substace emerged from it usw=ed to get solodifies as soon as it get to released to tthe atmosphere ! but i dont know was it c alled and now i need to know about it if any one among here know about any such thinkg then pkease let me know
thanking you in anticipation !