add feature to disable text-to-pixel snapping during layout #5057
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| ## The side effect of such rounding is that text layout will likely be inconsistent across | ||
| ## different values of `pixel_per_point`. Disabling such "snapping" will make the text fuzzy, | ||
| ## but the layout will remain constant across `pixels_per_point`. | ||
| disable_text_snapping = [] |
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I think this should be a runtime setting instead
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That makes sense. Let me revise it.
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To me, it makes the most sense to add this as a field of LayoutJob which would default to true for snapping. That would allow a user like myself to have, e.g., the UI elements all snap while retaining more granular control over a particular layout job. I'm not sure if adding a Struct field is considered a breaking change, so I'd welcome your thoughts on that. Thanks for a great library @emilk.
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I think adding it to LayoutJob is the right thing yes
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Note that we already have a setting for this, though maybe it is not by the actual text layout engine: https://docs.rs/epaint/latest/epaint/tessellator/struct.TessellationOptions.html#structfield.round_text_to_pixels |
My concerns are primarily around the layout of the text, so I haven't had a chance to investigate the interaction with tesselation, but I will. I'll come back to you. |
Recognizing that a switch to Cosmic Text is on the way per #56 , I also wanted to implement a temporary feature which disables what I call "text snapping"--i.e., where we round to the nearest pixel on the x and y axis when rendering text. This results in text being laid out in different ways across
pixel_per_pointvalues. Such snapping improves font rendering in the absence of other anti-aliasing approaches which will be provided by Cosmic Text. For some contexts, however, maintaining the layout is more important acrosspixel_per_pointvalues. This feature allows for that until Cosmic Text saves the day.