Platoon

01 · Section one

The jungle and the village

The whole map of the first section: 20 rows of 90 blocks from $A000, each block 8 by 6 characters from $8000. The screen shows five blocks across and three down at a time. The top three rows are drawn with the character set and colours the game swaps in when the soldier climbs up to them ($BAB6), the rest with the jungle's ($BAFD).

The jungle is six levels, each one scene high. Ladders join each level to the one below at the same place: pressing down on a ladder's foothold ($0EA7) takes the soldier down a level, and pressing up at its top ($0DE2) takes him back. The six huts on the top level have doors, and going up through one leads to the inside of that hut on the sixth level ($29B6), where the searches and the trapdoor are.

The route is the shortest walk between the jobs, worked out from the ladders and hut doors in the map data. After the bridge blows it keeps off the bridge. Tree trunks stop the soldier walking ($0F17, $0FAA), so the route goes round them by ladder. Before the bridge blows it stays short of the far side, where the patrol that ends the game waits. A hut door drops the soldier straight into that hut, so those jumps are drawn as long lines.

Join the levels: the insides of the huts are drawn at the top, above the village they open from. Joining hides most of the treetops between levels, so each ladder runs straight from one level into the next. The two block rows below the huts are left out: the lowest scene starts at the huts, so they are never on screen. Scroll sideways to follow the map. White tags mark where things happen ($3B25): ▶ the start ($0544), ■ the bridge, the explosives and the villager, ▼ the trapdoor down to the tunnels. Under each hut is what a search finds there ($CC8D): ★ the torch or the map, ✕ a booby trap, · an ordinary find. Tags sit where the soldier stands, two blocks into the scene; that offset is read from where the huts and their search ranges line up, not traced. The background and shared colours are the jungle band's: black, brown and light green ($057A-$058E).

02 · Section two

The tunnel map

The map in the corner of the tunnel screen is nine windows of 19 by 19 characters from $9C20, one shown at a time and swapped as the soldier nears an edge ($146B). Each character is a square: open tunnel (code 2), water (code 3), the walls' edges (codes 4 to 9), or rock.

Drawn by square kind, not with the game's characters: open tunnel pale, water marked with waves, edges grey, rock dark. Windows are numbered in the order of the table at $1390, whose last four entries point at room pictures instead.

03 · Section three

The map of the last jungle

The rooms sit on a grid ten wide and twelve high, numbered across from 0 ($3591). Each room has a kind from 1 to 16; kind 0 is outside the maze. The kind picks one of ten maps of 30 by 25 characters ($3609, $361A) and a list of trees, huts and other shapes drawn over it ($36D1), so rooms of the same kind look alike.

The whole maze, every room drawn at its place on the grid with its number; the soldier starts in room 105 (START), and the three rooms of kind 16 (BUNKER) are Barnes's, whose edges the room test at $33E7 handles apart from the others. Empty squares are outside the maze. The white line is the way to the bunker. Press a room to draw it larger below.

Walking off a room's left or right edge leads to a neighbouring room, but which neighbour depends on the way the soldier has turned: each exit rotates the four directions ($344A, $34A0), so the same edge can lead somewhere different on a later visit. The route is the shortest one through those rules, from START to the bunker, and says which edge to leave by in each room.