How Moving and Crumbling Platforms Are Designed

A static platform is a promise: land here and you will be fine. Every special platform type modifies that promise, and the design problem is making sure the player knows about the modification before they commit.

Moving platforms

Platforms travel on a sine path with a visible range and period. On this site, ranges run 40 to 90 units and periods 0.8 to 1.6 cycles per second.

A sine path is chosen over linear back-and-forth movement for a specific reason: it has no sudden direction changes. A platform that reverses instantly at the end of its travel can throw a player off, where a sine path decelerates into the turn and accelerates out of it. The movement is therefore predictable roughly a second ahead, which is enough to plan a landing.

Two rules keep them fair:

• The path is always fully visible. A platform never travels off screen and returns, because a player cannot plan around something they cannot see.
• Range is capped relative to the gap. A platform whose travel exceeds the jump distance to it would make some cycles unreachable, which would mean waiting rather than playing.

Crumbling platforms

A crumbling platform collapses 550 milliseconds after you land on it. During that window it shakes visibly and hairline cracks are drawn across its surface.

550 milliseconds is the number that makes this fair. It is long enough to react to — comfortably above the roughly 250-millisecond simple reaction time — and short enough that standing still is not an option.

The important design point is that the platform is identifiable before you land on it, not just after. Crumbling platforms are drawn with crack marks from the moment they appear, so the shake is a countdown rather than a surprise.

Bounce platforms

Pancake Hopper's syrup platforms launch you at 1,180 units per second against a normal jump of 760 — about 55% more, which in practice clears three or four platforms instead of one.

The signalling problem here is the hardest of the three, because the modification is beneficial rather than dangerous. A player who misses a crumbling platform's warning loses a life; a player who misses a bounce platform's marking simply does not get the bonus, which is a much weaker feedback signal.

The solution is an amber band along the platform's top edge with three animated drips hanging beneath it. It is visible from across the screen, it animates so it catches peripheral attention, and it uses a colour that appears nowhere else in that game's palette.

One-way platforms

Every platform in the climbing games is one-way: you land on the top but pass through from below.

The implementation detail that makes this work is checking the player's previous position rather than their current one. The landing only registers if the player's bottom edge was above the platform's top edge in the previous frame and is below it now. Without that check, a player rising fast through a platform can be caught on it mid-ascent, which feels like the game grabbing you.

Gravity Kitchen extends this: under inverted gravity, the same check runs against the platform's bottom edge, so you land on the underside.

What makes a special platform fair

1. It is identifiable before you commit. Visual marking from the moment it appears, not from the moment it activates.
2. Its behaviour is predictable. A sine path, a fixed warning duration, a fixed bounce multiplier — never a random one.
3. The warning window exceeds reaction time. 550 milliseconds against a roughly 250-millisecond floor.
4. The marking is unique in the palette. Amber drips appear nowhere else; crack marks appear nowhere else.
5. It is used sparingly. Roughly one platform in five for bounce, one in seven for crumbling. A tower made entirely of special platforms has no baseline to contrast against.

That last point is the one most often missed. Special platforms derive their meaning from the static ones around them. If everything is special, nothing is.

Frequently Asked Questions