Fix lack of slider encode-decode stability due to truncating control point coordinates on decode #33615
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…point coordinates Mostly closes ppy#33505. Compare https://github.com/ppy/osu/blob/97e6187f0d7c3dbee896596a623e34627135bf0e/osu.Game/Rulesets/Objects/Legacy/ConvertHitObjectParser.cs#L56-L59 I say "mostly" here because I'm rather skeptical that this is 100% rock solid still, for one reason - namely that the game stores path control point coordinates relative to the head, then turns them into absolute coordinates when encoding, and then on decoding turns them back into coordinates relative to the head, which in floating-point world is a Bad Idea because of round-off error. But I'm not fixing that without introducing a completely new beatmap format or rewriting half the editor to address that, so I'll just pretend that I don't know any of this until someone notices.
bdach
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bdach
commented
Jun 10, 2025
| { | ||
| string[] vertexSplit = value.Split(':'); | ||
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| Vector2 pos = new Vector2((int)Parsing.ParseDouble(vertexSplit[0], Parsing.MAX_COORDINATE_VALUE), (int)Parsing.ParseDouble(vertexSplit[1], Parsing.MAX_COORDINATE_VALUE)) - startPos; |
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I'm reasonably confident that ParseDouble() was gratuitous here because IHas[XY]?Position are all single precision-based anyway.
smoogipoo
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Jun 26, 2025
This was referenced Sep 5, 2025
This was referenced Oct 3, 2025
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Mostly closes #33505.
Compare
osu/osu.Game/Rulesets/Objects/Legacy/ConvertHitObjectParser.cs
Lines 56 to 59 in 97e6187
I say "mostly" here because I'm rather skeptical that this is 100% rock solid still, for one reason - namely that the game stores path control point coordinates relative to the head in memory, then turns them into absolute coordinates when encoding, and then on decoding turns them back into coordinates relative to the head, which in floating-point world is a Bad Idea because of round-off error. But I'm not fixing that without introducing a completely new beatmap format or rewriting half the editor to address that, so I'll just pretend that I don't know any of this until someone notices.
Not sure if we want to run any diffcalc here to validate this.