[kqr]

I also had performance issues in Firefox, so I tried something else: just holding the up key. It was surprisingly effective. Not that it didn't fail a lot, but it progressed through the levels at a fairly even pace.

Unless I misunderstand the maths, the hold-up strategy has the same probability of winning regardless of which level one is at, since the levels only increase the speed of the obstacles and not their density. I would have thought the difficulty would ramp up such that even stupid strategies get less effective at higher levels, but not this time!

[jstanley]

> the levels only increase the speed of the obstacles and not their density.

But your speed is the same at every level.

Instead of looking at the width of each obstacle, instead look at the amount of space that the obstacle covers during the time you are in its path. If it moves faster then it covers more space during the time it takes you to cross, so it is effectively wider.

Imagine if the obstacles moved so fast that they crossed from one side of the screen to the other in the time it takes you to move up one line. You would never be able to pass any obstacle.

[kqr]

I was under the impression my speed was one unit distance per frame. That would mean the speed of the obstacles is irrelevant becuse either they are in my location in that one frame or they are not -- and it doesn't matter how fast they go.

Edit: actually thanks to their double thickness it does matter! I didn't think of that.

[fweimer]

I suppose it depends on how collision detection is implemented. Maybe the cars tunnel through the frog at later levels? Although it does not seem to get easier at higher levels (got up to level 62 using the potato method).