Metal Gear (MSX) PS2 port has a full map system and loads screens individually from those maps. Only some changes are cutscenes playing. See below per map how they're stored in memory and which screen is placed where. Click on the maps to zoom in and eventually getting to the 100% resolution when loading the original file. When a screen has two values, that means that the screen has multiple positions for its guards. For example map 1 screen 1,2: depending on if Snake arrives on the screen from the south or coming from east or north, the guards are either placed higher on the screen or lower.
The most simple and yet iconic screen of the Metal Gear franchise. Even MGS, MGS2 and MGS3 have a dock.
The second map is ordered as we reach it in the game, gound from the ground up two floors with the elevator.
Builind 1's underground is not just the maze, but also the holding Cells where Snake gets put after being captured. In the north we can also find Ellen, Dr. Madnar's daughter.
Map 6 has finally reached the elevator of Building 1, yet the next map is the final map of building 1.
Map 7 contains the roof. The image of Snake parachuting down is actually cutscene as no change in the map and floor values are being recorded. This might also explain why snake falls immediately from the roof to the ground floor without the snake falling animation at all.
The first part of the swim towards Dirty Duck is still part of the ground floor map. Only the final screen when arriving at the top end is part of Building 3.
The underground and it's bowel connecting Building 1 and Building 2 are still part of the Building 2 underground map, not their own map.
Note the trucks at the top teleport Snake back to prior teleport truck at the center of Building 1 or the Desert 1 ration truck.
The Map containing the three ladders. At the top, another cutscene plays which then transports snake away to let the end credits roll in the codec screen.