4 ms·

Allsorts: font parser and shaping engine implemented in Rust

125 points by wezm 7y ago

j88439h84 7y ago
Cool. Are you in contact with the Runebender devs at all? https://github.com/linebender/runebender https://github.com/linebender/runebender
- chrismorgan 7y ago
  Yes, they’re in contact on https://xi.zulipchat.com/ https://xi.zulipchat.com/.
- raphlinus 7y ago
  Yes, we've been in touch, and I'm really excited to see this.
riquito 7y ago
So cool, I was going to ask what was the relationship with something like pathfinder [1], but you already addressed it in your github README. Thanks for contributing in this space [1] https://github.com/servo/pathfinder/blob/master/README.md https://github.com/servo/pathfinder/blob/master/README.md
imoldfella 7y ago
How does this compare to harfbuzz?
- mikeday 7y ago
  HarfBuzz is more complete (supports more scripts) and higher performance (we assume, haven't benchmarked yet), but the large C++ codebase can be a little intimidating to dive into. We plan to extend Allsorts to reach feature parity with HarfBuzz, so it will be an interesting comparison of tackling a complex problem in Rust!
xvilka 7y ago
This would certainly be beneficial for the XeTeX "oxidation" efforts[1] for fonts parsing and shaping[2]. There is also a number of existing alternatives: font-kit[3], Skribo[4], RustType[5], ttf-parser[6]. Some of them are just parsers, some - font shapers. Still all of them are relevant to the subject. [1] https://github.com/crlf0710/tectonic https://github.com/crlf0710/tectonic [2] https://github.com/crlf0710/tectonic/issues/117 https://github.com/crlf0710/tectonic/issues/117 [3] https://github.com/servo/font-kit https://github.com/servo/font-kit [4] https://github.com/linebender/skribo https://github.com/linebender/skribo [5] https://gitlab.redox-os.org/redox-os/rusttype/ https://gitlab.redox-os.org/redox-os/rusttype/ [6] https://github.com/RazrFalcon/ttf-parser https://github.com/RazrFalcon/ttf-parser
pcwalton 7y ago
Great to see more work in this space. Diversity of font parsing and shaping engines is important to make sure the ecosystem doesn't become reliant on bug-for-bug compatibility with the existing engines. (It's dangerously close already, due to the quirks of DirectWrite, GDI, and FreeType.)
- wezm 7y ago
  Yes, this was definitely part of the motivation for embarking on this project.
- bjz_ 7y ago
  Yeah! This was a big reason why we've invested in funding the work on https://github.com/n8willis/opentype-shaping-documents/ https://github.com/n8willis/opentype-shaping-documents/ - hopefully this makes the barrier to entry to building font shaping engines a little lower for newcomers, and gives us a place to document findings, separate from any single implementation.
  - jeltz 7y ago
    Have any bugs been discovered and reported in the other implementations due to this work?
    - adrianwongy 7y ago
      Not bugs per se, but a couple of improvements were fed back to HarfBuzz's Indic shaper. The first was a minor optimisation to the final reordering of pre-base matras; the second was an adjustment to the output of the Indic table generator.
pcr910303 7y ago
Obligatory article: Text Rendering Hates You [0][1] [0] https://gankra.github.io/blah/text-hates-you/ https://gankra.github.io/blah/text-hates-you/ [1] https://news.ycombinator.com/item?id=21105625 https://news.ycombinator.com/item?id=21105625
devit 7y ago
I'm curious about why they decided to develop Allsorts instead of just using Harfbuzz.
- wezm 7y ago
  pcwalton captures it pretty well in a comment above: https://news.ycombinator.com/item?id=21580718 https://news.ycombinator.com/item?id=21580718 that and wanting to have an implementation in a memory safe language that might prove useful to others.
earthboundkid 7y ago
I used Prince for everything I wrote in grad school. A truly beautiful PDF maker. It's cool that they're releasing part of it.

125 points by wezm 7y ago

Cool. Are you in contact with the Runebender devs at all? https://github.com/linebender/runebender https://github.com/linebender/runebender

chrismorgan 7y ago
Yes, they’re in contact on https://xi.zulipchat.com/ https://xi.zulipchat.com/.
raphlinus 7y ago
Yes, we've been in touch, and I'm really excited to see this.

riquito 7y ago

So cool, I was going to ask what was the relationship with something like pathfinder [1], but you already addressed it in your github README. Thanks for contributing in this space [1] https://github.com/servo/pathfinder/blob/master/README.md https://github.com/servo/pathfinder/blob/master/README.md

imoldfella 7y ago

How does this compare to harfbuzz?

mikeday 7y ago
HarfBuzz is more complete (supports more scripts) and higher performance (we assume, haven't benchmarked yet), but the large C++ codebase can be a little intimidating to dive into. We plan to extend Allsorts to reach feature parity with HarfBuzz, so it will be an interesting comparison of tackling a complex problem in Rust!

xvilka 7y ago

This would certainly be beneficial for the XeTeX "oxidation" efforts[1] for fonts parsing and shaping[2]. There is also a number of existing alternatives: font-kit[3], Skribo[4], RustType[5], ttf-parser[6]. Some of them are just parsers, some - font shapers. Still all of them are relevant to the subject. [1] https://github.com/crlf0710/tectonic https://github.com/crlf0710/tectonic [2] https://github.com/crlf0710/tectonic/issues/117 https://github.com/crlf0710/tectonic/issues/117 [3] https://github.com/servo/font-kit https://github.com/servo/font-kit [4] https://github.com/linebender/skribo https://github.com/linebender/skribo [5] https://gitlab.redox-os.org/redox-os/rusttype/ https://gitlab.redox-os.org/redox-os/rusttype/ [6] https://github.com/RazrFalcon/ttf-parser https://github.com/RazrFalcon/ttf-parser

pcwalton 7y ago

Great to see more work in this space. Diversity of font parsing and shaping engines is important to make sure the ecosystem doesn't become reliant on bug-for-bug compatibility with the existing engines. (It's dangerously close already, due to the quirks of DirectWrite, GDI, and FreeType.)

wezm 7y ago
Yes, this was definitely part of the motivation for embarking on this project.
bjz_ 7y ago
Yeah! This was a big reason why we've invested in funding the work on https://github.com/n8willis/opentype-shaping-documents/ https://github.com/n8willis/opentype-shaping-documents/ - hopefully this makes the barrier to entry to building font shaping engines a little lower for newcomers, and gives us a place to document findings, separate from any single implementation.
- jeltz 7y ago
  Have any bugs been discovered and reported in the other implementations due to this work?
  - adrianwongy 7y ago
    Not bugs per se, but a couple of improvements were fed back to HarfBuzz's Indic shaper. The first was a minor optimisation to the final reordering of pre-base matras; the second was an adjustment to the output of the Indic table generator.

pcr910303 7y ago

Obligatory article: Text Rendering Hates You [0][1] [0] https://gankra.github.io/blah/text-hates-you/ https://gankra.github.io/blah/text-hates-you/ [1] https://news.ycombinator.com/item?id=21105625 https://news.ycombinator.com/item?id=21105625

devit 7y ago

I'm curious about why they decided to develop Allsorts instead of just using Harfbuzz.

wezm 7y ago
pcwalton captures it pretty well in a comment above: https://news.ycombinator.com/item?id=21580718 https://news.ycombinator.com/item?id=21580718 that and wanting to have an implementation in a memory safe language that might prove useful to others.

earthboundkid 7y ago

I used Prince for everything I wrote in grad school. A truly beautiful PDF maker. It's cool that they're releasing part of it.