Ladder

Ladders stand in the rooms of the Mines and the Temple, where they link a room's floors, and, in the Jungle, only in the Black Market. The top of one is a ladder top, a rung the player can also stand on. The Jungle's rooms have Vines where the others have ladders, and a thrown Rope is, to the code, one more kind of ladder.

The clip shows the whole of it: the player walks to a ladder, presses up and climbs it to its top, then jumps off toward the ledge beside it, catches the ledge's edge and pulls himself up.

The player takes hold of a ladder by pressing up while he's in it, or while he's in the air with a ladder just above him. He must be within 4 pixels of the ladder's middle, sideways, and he's put on its middle when he takes hold, his speed stopped ^[2]. Pressing down on a platform with a ladder under it, a ladder top among them, takes hold of it too, and he climbs down ^[3]. Ducking over a ledge with a ladder beside its edge takes hold of the ladder rather than hanging from the edge ^[4].

On a ladder, up and down move the player for as long as the ladder goes on above or below him: each step adds 0.6 to his speed, and climbing's friction takes 0.4 of it away again ^{[5] [6] [7] [8]}. In play that's 1 pixel a step (30 a second), a block in 16 steps ^[9]. Left and right only turn him ^[10]. A Cape closes while he climbs ^[11], and a fall doesn't count while he's climbing, so climbing down never ends in a long drop's stun ^[12].

• At the foot. Pressing down where the ladder ends lets go, and the player falls; one who reaches the ground pressing down stands on it ^[13].
• Jumping. The jump key throws the player off with an upward push, sideways at 4 pixels per step if left or right is held, or straight up without ^{[14] [15]}. For 5 steps after, he can't take hold of a ladder again ^[16].

Ladders are made by the room templates' ladder and ladder top tiles:

The Tutorial has ladders the room editor placed ^[20], and the title screen builds one of its own ^[21]. In custom levels they're the level editor's tiles L (a ladder) and P (a ladder top) ^[22].

• Ropes are a kind of ladder to the code, as are Vines: the checks for a ladder find them too, so the player takes hold of them and climbs them in the same way ^[2].
• Monkeys leaping through the air catch hold of a ladder as they do a vine ^[23].
• Bombs don't destroy ladders: a blast destroys the solid blocks it touches and the Spikes it leaves with nothing under them, and a ladder is neither ^[24], so it stays standing where it was.

• Climbing down a long ladder is safe however far it goes; dropping off it partway isn't, as the fall counts from where he lets go.
• Jumping off with a direction held carries the player sideways at 4 pixels per step, faster than he walks, onto a ledge beside the ladder.

• The object level generation places is an orange ladder, a kind of the plain ladder object that has no events of its own: the parent is never placed ^[25].
• A test for touching a ladder looks for a ladder top first, then a ladder, in the middle of the player's box ^[26].