91674d5a49
Try to ensure that using "the width computed during an unconstrained layout" as the width constraint during a relayout produces the same layout. This is useful for certain UI layout algorithms. See https://github.com/pop-os/cosmic-text/issues/134 * Instead of computing the LayoutLine width from the positioned and aligned glyphs, we pass through width computed during line wrapping (unless justified alignment is used, in this case we use the old approach because the use case for measuring the width isn't really applicable to justified text since that will just expand to the provided width). For the produced width to later give the same wrapping results when passed in as the `line_width` it needs to use the same exact float arithmatic that was used to compute the width that is compared against `line_width` when making line wrapping choices. Passing this width through as the LayoutLine width is the most covenient option without making more major changse to the API. Nevertheless, I am imagining that if we get a dedicated measurement method (i.e. that doesn't do the final positioning and alignment of glyphs and which caches `Vec<VisualLine>`), then this width can just be exposed there instead of preservering it in LayoutLine. * Incidentally, this fixes https://github.com/pop-os/cosmic-text/issues/169. * Switch substraction from `fit_x` to checking whether potential addition to the current line width would exceed the `line_width`. This avoids the float error being dependent on the provided `line_width` value. * When eliminating trailing space from the line width, we avoid backtracking with subtraction (which would not give the same exact value due to float error) and instead save the previous width and use that. * If the previous word did not exceed the line_width, we now include a single blank word even if it would cross the width limit since its width won't be counted. This is necessary to get the same wrapping behavior when re-using the measured width (which doesn't count a single trailing blank word). Note, this whitespace logic may be reworked anyway if <https://github.com/pop-os/cosmic-text/issues/155> is addressed. * Change tests to use `opt-level=1` to keep test runtime down. * Add `fonts` folder for fonts used in tests. * Fix an issue where a non-breaking whitespace was assumed to be the start of a section of spaces which included characters that weren't even whitespace. * Add some TODOs about incongruencies between `is_whitespace`, justification, and line breaks.
93 lines
4.3 KiB
Text
93 lines
4.3 KiB
Text
Digitized data copyright (c) 2012-2015, The Mozilla Foundation and Telefonica S.A.
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This Font Software is licensed under the SIL Open Font License, Version 1.1.
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This license is copied below, and is also available with a FAQ at:
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http://scripts.sil.org/OFL
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-----------------------------------------------------------
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SIL OPEN FONT LICENSE Version 1.1 - 26 February 2007
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-----------------------------------------------------------
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PREAMBLE
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The goals of the Open Font License (OFL) are to stimulate worldwide
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development of collaborative font projects, to support the font creation
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efforts of academic and linguistic communities, and to provide a free and
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open framework in which fonts may be shared and improved in partnership
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with others.
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The OFL allows the licensed fonts to be used, studied, modified and
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redistributed freely as long as they are not sold by themselves. The
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fonts, including any derivative works, can be bundled, embedded,
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redistributed and/or sold with any software provided that any reserved
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names are not used by derivative works. The fonts and derivatives,
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however, cannot be released under any other type of license. The
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requirement for fonts to remain under this license does not apply
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to any document created using the fonts or their derivatives.
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DEFINITIONS
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"Font Software" refers to the set of files released by the Copyright
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Holder(s) under this license and clearly marked as such. This may
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include source files, build scripts and documentation.
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"Reserved Font Name" refers to any names specified as such after the
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copyright statement(s).
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"Original Version" refers to the collection of Font Software components as
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distributed by the Copyright Holder(s).
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"Modified Version" refers to any derivative made by adding to, deleting,
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or substituting -- in part or in whole -- any of the components of the
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Permission is hereby granted, free of charge, to any person obtaining
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in Original or Modified Versions, may be sold by itself.
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2) Original or Modified Versions of the Font Software may be bundled,
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redistributed and/or sold with any software, provided that each copy
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Software shall not be used to promote, endorse or advertise any
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distributed under any other license. The requirement for fonts to
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THE FONT SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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