During Metal Gear’s existence, beginning in 1987, game development went through tremendous technological advancements. Kojima posted a picture that compares the faces of what Snake looked back in 1998, when he appeared as a 3D character model for the first time, and what he looks like today.
“This morning Johnny gave presentation to our freshmen in Kojima Productions. “Game development now and then”.”
In another Tweet related to the subject Kojima said:
“There’d been 2 big heaps in terms of technical expression of pic, when 3D polygon arrived in consumer game & when normal vector map arrived.”
Metal Gear Solid on PlayStation was the first game where Kojima made use of polygons.
Source: Hideo Kojima Twitter