xP: produce a custom font for IRC formatting

Given that the generated file needs a manual adjustment,
its small size, and the dependencies involved,
it will be checked in to the repository.

CMakeLists.txt

@@ -1,7 +1,7 @@
 # Ubuntu 18.04 LTS and OpenBSD 6.4
 cmake_minimum_required (VERSION 3.10)
 project (xK VERSION 1.5.0
-	DESCRIPTION "IRC daemon, bot, TUI client and X11/web frontends" LANGUAGES C)
+	DESCRIPTION "IRC daemon, bot, TUI client and its web frontend" LANGUAGES C)
 
 # Options
 option (WANT_READLINE "Use GNU Readline for the UI (better)" ON)

NEWS

@@ -27,9 +27,7 @@
 
  * xC: added a relay interface, enabled through the general.relay_bind option
 
- * Added an experimental X11 frontend for xC called xF
-
- * Added an experimental web frontend for xC called xP
+ * Added a web frontend for xC called xP
 
 
 1.5.0 (2021-12-21) "The Show Must Go On"

README.adoc

@@ -2,7 +2,7 @@ xK
 ==
 
 'xK' (chat kit) is an IRC software suite consisting of a daemon, bot, terminal
-client, and X11/web frontends for the client.  It's all you're ever going to
+client, and a web frontend for the client.  It's all you're ever going to
 need for chatting, so long as you can make do with slightly minimalist software.
 
 They're all lean on dependencies, and offer a maximally permissive licence.
@@ -26,16 +26,9 @@ As a unique bonus, you can launch a full text editor from within.
 xP
 --
 The web frontend for 'xC', making use of its networked relay interface.
-Fully usable, despite some rough edges.  It intentionally differs in that it
-uses a sans-serif font, and shows the list of all buffers in a side panel.
-Otherwise it aims to be a near replica.
-
-xF
---
-The X11 frontend for 'xC', making use of its networked relay interface.
-
-This subproject has been put on hold, partly because of its massive overlap
-with 'xP', and is hidden behind a CMake option.
+It intentionally differs in that it uses a sans-serif font, and it shows
+the list of all buffers in a side panel.  Otherwise it is a near replica,
+including keyboard shortcuts.
 
 xD
 --
@@ -78,7 +71,6 @@ Build-only dependencies:
 Common runtime dependencies: openssl +
 Additionally for 'xC': curses, libffi, readline >= 6.0 or libedit >= 2013-07-12,
  lua >= 5.3 (optional) +
-Additionally for 'xF': x11, xft
 
  $ git clone --recursive https://git.janouch.name/p/xK.git
  $ mkdir xK/build

xC.c

@@ -15025,6 +15025,7 @@ process_formatting_escape (const struct pollfd *fd, struct app_context *ctx)
 	case 'u':
 	case '_': CALL_ (ctx->input, insert, "\x1f"); break;
 	case 'v': CALL_ (ctx->input, insert, "\x16"); break;
+	case 'r':
 	case 'o': CALL_ (ctx->input, insert, "\x0f"); break;
 
 	default:

xP/Makefile

@@ -2,7 +2,7 @@
 .SUFFIXES:
 
 outputs = xP proto.go public/proto.js public/mithril.js
-all: $(outputs)
+all: $(outputs) public/ircfmt.woff2
 
 xP: xP.go proto.go
 	go build -o $@
@@ -10,6 +10,8 @@ proto.go: ../xC-gen-proto.awk ../xC-gen-proto-go.awk ../xC-proto
 	awk -f ../xC-gen-proto.awk -f ../xC-gen-proto-go.awk ../xC-proto > $@
 public/proto.js: ../xC-gen-proto.awk ../xC-gen-proto-js.awk ../xC-proto
 	awk -f ../xC-gen-proto.awk -f ../xC-gen-proto-js.awk ../xC-proto > $@
+public/ircfmt.woff2: gen-ircfmt.awk
+	awk -v Output=$@ -f gen-ircfmt.awk
 public/mithril.js:
 	curl -Lo $@ https://unpkg.com/mithril/mithril.js
 clean:

xP/gen-ircfmt.awk

@@ -0,0 +1,89 @@
+# gen-ircfmt.awk: generate a supplementary font for IRC formatting characters
+#
+# Copyright (c) 2022, Přemysl Eric Janouch <p@janouch.name>
+# SPDX-License-Identifier: 0BSD
+#
+# Usage: awk -v Output=static/ircfmt.woff2 -f gen-ircfmt.awk
+# Clean up SVG byproducts yourself.
+
+BEGIN {
+	if (!Output) {
+		print "Error: you must specify the output filename"
+		exit 1
+	}
+}
+
+function glyph(name, code, path,    filename, actions, cmd) {
+	filename = Output "." name ".svg"
+
+	# Inkscape still does a terrible job at the stroke-to-path conversion.
+	actions = \
+		"select-by-id:group;" \
+		"selection-ungroup;" \
+		"select-clear;" \
+		"select-by-id:path;" \
+		"object-stroke-to-path;" \
+		"select-by-id:clip;" \
+		"path-intersection;" \
+		"select-all;" \
+		"path-combine;" \
+		"export-overwrite;" \
+		"export-filename:" filename ";" \
+		"export-do"
+
+	# These dimensions fit FontForge defaults, and happen to work well.
+	cmd = "inkscape --pipe --actions='" actions "'"
+	print "<?xml version='1.0' encoding='UTF-8' standalone='no'?>\n" \
+		"<svg version='1.1' xmlns='http://www.w3.org/2000/svg'\n" \
+		" width='1000' height='1000' viewBox='0 0 1000 1000'>\n" \
+		"  <rect x='0' y='0' width='1000' height='1000' />\n" \
+		"  <g id='group' transform='translate(200 200) scale(60, 60)'>\n" \
+		"    <rect id='clip' x='0' y='0' width='10' height='10' />\n" \
+		"    <path id='path' stroke-width='2' fill='none' stroke='#fff'\n" \
+		"     d='" path "' />\n" \
+		"  </g>\n" \
+		"</svg>\n" | cmd
+	close(cmd)
+
+	print "Select(0u" code ")\n" \
+		"Import('" filename "')" | FontForge
+}
+
+BEGIN {
+	FontForge = "fontforge -lang=ff -"
+	print "New()" | FontForge
+
+	# Designed a 10x10 raster, going for maximum simplicity.
+	glyph("B", "02", "m 6,5 c 0,0 2,0 2,2 0,2 -2,2 -2,2 h -3 v -8 h 2.5 c 0,0 2,0 2,2 0,2 -2,2 -2,2 h -2 Z")
+	glyph("C", "03", "m 7.6,7 A 3,4 0 0 1 4.25,8.875 3,4 0 0 1 2,5 3,4 0 0 1 4.25,1.125 3,4 0 0 1 7.6,3")
+	glyph("I", "1D", "m 3,9 h 4 m 0,-8 h -4 m 2,-1 v 10")
+	glyph("M", "11", "m 2,10 v -10 l 3,6 3,-6 v 10")
+	glyph("O", "0F", "m 1,9 l 8,-8 M 2,5 a 3,3 0 1 0 6,0 3,3 0 1 0 -6,0 z")
+	#glyph("R", "0F", "m 3,10 v -9 h 2 c 0,0 2.5,0 2.5,2.5 0,2.5 -2.5,2.5 -2.5,2.5 h -2 2.5 l 2.5,4.5")
+	glyph("S", "1E", "m 7.5,3 c 0,-1 -1,-2 -2.5,-2 -1.5,0 -2.5,1 -2.5,2 0,3 5,1 5,4 0,1 -1,2 -2.5,2 -1.5,0 -2.5,-1 -2.5,-2")
+	glyph("U", "1F", "m 2.5,0 v 6.5 c 0,1.5 1,2.5 2.5,2.5 1.5,0 2.5,-1 2.5,-2.5 v -6.5")
+	glyph("V", "16", "m 2,-1 3,11 3,-11")
+
+	# In practice, your typical browser font will overshoot its em box,
+	# so to make the display more cohesive, we need to do the same.
+	# Sadly, sf->use_typo_metrics can't be unset from FontForge script--
+	# this is necessary to prevent the caret from jumping upon the first
+	# inserted non-formatting character in xP's textarea.
+	# https://iamvdo.me/en/blog/css-font-metrics-line-height-and-vertical-align
+	print "SelectAll()\n" \
+		"Scale(115, 115, 0, 0)\n" \
+		"SetOS2Value('WinAscentIsOffset', 1)\n" \
+		"SetOS2Value('WinDescentIsOffset', 1)\n" \
+		"SetOS2Value('HHeadAscentIsOffset', 1)\n" \
+		"SetOS2Value('HHeadDescentIsOffset', 1)\n" \
+		"CorrectDirection()\n" \
+		"AutoWidth(100)\n" \
+		"AutoHint()\n" \
+		"AddExtrema()\n" \
+		"RoundToInt()\n" \
+		"SetFontNames('IRCFormatting-Regular'," \
+		" 'IRC Formatting', 'IRC Formatting Regular', 'Regular'," \
+		" 'Copyright (c) 2022, Premysl Eric Janouch')\n" \
+		"Generate('" Output "')\n" | FontForge
+	close(FontForge)
+}

xP/public/xP.css

@@ -1,7 +1,14 @@
+@font-face {
+	src: url('ircfmt.woff2') format('woff2');
+	font-family: 'IRC Formatting';
+	font-weight: normal;
+	font-style: normal;
+}
 body {
 	margin: 0;
 	padding: 0;
-	font-family: sans-serif;
+	/* Firefox only renders C0 within the textarea, why? */
+	font-family: 'IRC Formatting', sans-serif;
 	font-size: clamp(0.5rem, 2vw, 1rem);
 }
 .xP {
@@ -133,7 +140,7 @@ button:hover:active {
 	font-family: monospace;
 	overflow-y: auto;
 }
-.log, .content {
+.log, .content, .completions {
 	/* Note: https://bugs.chromium.org/p/chromium/issues/detail?id=1261435 */
 	white-space: break-spaces;
 	overflow-wrap: break-word;