From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Lars Ingebrigtsen Newsgroups: gmane.emacs.devel Subject: Re: Ligature support Date: Fri, 05 Nov 2021 15:38:12 +0100 Message-ID: <878ry2k6qz.fsf@gnus.org> References: <87cznths5j.fsf@gnus.org> <8ff3b131c5fa370d9eaf@heytings.org> <83mtmttsxz.fsf@gnu.org> <8ff3b131c56b7b2d1d6f@heytings.org> <83bl39tqnl.fsf@gnu.org> <8ff3b131c531f5254799@heytings.org> <83a6ittp5r.fsf@gnu.org> <8ff3b131c53b9df49236@heytings.org> <834k91th5c.fsf@gnu.org> <8ff3b131c5fe09753ca0@heytings.org> <83mtmtru6l.fsf@gnu.org> <8ff3b131c57f741d04e5@heytings.org> <83lf2drqx6.fsf@gnu.org> <87lf2c3k0z.fsf@gnus.org> <83wnlwqocq.fsf@gnu.org> <87wnlwyox9.fsf@gnus.org> <83lf2cq7n5.fsf@gnu.org> <87wnlnkxbo.fsf@gnus.org> <83cznfdohr.fsf@gnu.org> <87zgqik9bk.fsf@gnus.org> <83v916d64z.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="13811"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux) Cc: mattiase@acm.org, raman@google.com, gregory@heytings.org, schwab@linux-m68k.org, stefankangas@gmail.com, emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Fri Nov 05 15:44:03 2021 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mj0Rm-0003KN-S9 for ged-emacs-devel@m.gmane-mx.org; Fri, 05 Nov 2021 15:44:02 +0100 Original-Received: from localhost ([::1]:43670 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mj0Rl-0000WJ-Qu for ged-emacs-devel@m.gmane-mx.org; Fri, 05 Nov 2021 10:44:01 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:49878) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mj0MU-0001pU-KD for emacs-devel@gnu.org; Fri, 05 Nov 2021 10:38:34 -0400 Original-Received: from quimby.gnus.org ([2a01:4f9:2b:f0f::2]:58156) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mj0MS-0007l8-9L; Fri, 05 Nov 2021 10:38:34 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnus.org; s=20200322; h=Content-Type:MIME-Version:Message-ID:In-Reply-To:Date: References:Subject:Cc:To:From:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=Y5oCoavH+P8yROBW53QdYnKXMfyj7gMbT4J00M8JgRA=; b=KuBy/naBJUTN3BIGADVhM92EUo fDYpVQViJO5tCO2Hy8dhZSnhtPBSx1MdwwP4kpztDEDIozdxBpzjYn5l/QbLd/zUtxSd5DB0ak13t FGzQuKdFdsPUlCeA42c90/L3Vh/jrcKvQILUUy3hvTR6mRDMFlbbsuUhdusiLAnB9H0I=; Original-Received: from [84.212.220.105] (helo=elva) by quimby.gnus.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mj0M9-0005ZN-O0; Fri, 05 Nov 2021 15:38:19 +0100 Face: iVBORw0KGgoAAAANSUhEUgAAADAAAAAwBAMAAAClLOS0AAAABGdBTUEAALGPC/xhBQAAACBj SFJNAAB6JgAAgIQAAPoAAACA6AAAdTAAAOpgAAA6mAAAF3CculE8AAAALVBMVEUXExQhGxwuKi1Z LzkpJ2QjGygrK4lkU4jVnXTOLiCuSDmiJRzbTDLoa07////QtD2nAAAAAWJLR0QOb70wTwAAAAd0 SU1FB+ULBQ4cN54HNOoAAAF7SURBVDjLnZQxTwIxFMdfD1i4pWdgcIMT4ooysUG8wCpGPoGE+AEw YXRwcHBzau5ucHJwYjDmxMXBoaG3QwLfxV69wqW0Ufwnl7T9vff+fbm2gAAwcrLCgDDCYGGoglXB R4AqcMpHAAlogJSDHP4hHrojlIQ6zi7AODFDoEnhxRxNKYP+HrmveOd6UP11EwduzatduK6rhpZG XGPP8zoacH2XBdYWXGVABdAG9NqFodftKHsojYaTRr437Go8JreXvfFIBXnu0W4d3zT7slQuBV7z uWG/nZGp7Dw1L7LFg28/tsIvxdxmMfUPic+eFI8iDanfiqLwUwE2iVeEkCDYZKSd236wYmtGJcDS nAO+vs6AVDkSxWsaU6YBi/t5uGRTdbtkFi/mH0vZ4NZ8NQuoH5Ft57LUy0zo/VVM0QaUkytTHtQH AzHVnPkfGc82Mh04fAIFfUbf5GEy/8d1qZtA1bC+v4VMsZKi/Lmp8xF/a4SHaAWlf1/EnYuMb6sp Z/wCmHAZAAAAJXRFWHRkYXRlOmNyZWF0ZQAyMDIxLTExLTA1VDE0OjI4OjU0KzAwOjAweco8mAAA ACV0RVh0ZGF0ZTptb2RpZnkAMjAyMS0xMS0wNVQxNDoyODo1NCswMDowMAiXhCQAAAAASUVORK5C YII= X-Now-Playing: Django Django's _Glowing In The Dark_: "Glowing In The Dark" In-Reply-To: <83v916d64z.fsf@gnu.org> (Eli Zaretskii's message of "Fri, 05 Nov 2021 16:33:16 +0200") Received-SPF: pass client-ip=2a01:4f9:2b:f0f::2; envelope-from=larsi@gnus.org; helo=quimby.gnus.org X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.io gmane.emacs.devel:278773 Archived-At: Eli Zaretskii writes: > So for having ligatures you need to set up composition-function-table > for the characters that could/should ligate. Yes. And to do that, we can parse the tables in the font, apparently. It's not obviously clear how, but it looks like harfbuzz has the functions needed. > But please read the TODO item: there are pitfalls here that we need to > solve before this could be considered a reasonable user-level > feature. Setting up composition-function-table to produce ligatures > for, say, "fi" and "ff" is easy for testing, but if you do that in > production, every word with these characters, everywhere on display in > Emacs, will display as that ligature, and that is hardly TRT. We need > to make this more fine-tunable. TODO has the details. I guess it needs some more customisation to be a per-font thing? But first we need to parse the Gsub/Gpos tables so that we can get started at all. -- (domestic pets only, the antidote for overdose, milk.) bloggy blog: http://lars.ingebrigtsen.no