Sorry if you already answered these questions, but did you give the solution for a speed of 1.25 and using a for loop in the tile_meeting function, doesn't that affect performance too much?
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I was hoping that the issue would sort of "auto resolve" with the new floating point collision detection. Though I haven't tested recently with those changes. I had a solution in the past, but it was very complicated, and it's much easier to set your speed to 1.251 or something.
And as a rule, we don't worry about performance until there is a tangible issue. So as far as I know, there is nothing to be concerned about performance wise.