From 6c6240c46c33a85f3c78f752d25416413a83e201 Mon Sep 17 00:00:00 2001
From: Mischa POSLAWSKY <perl@shiar.org>
Date: Tue, 2 Nov 2021 01:02:43 +0100
Subject: [PATCH] codec: derive column groups from generation sequence

Not specific to hardcoded image formats.
---
 codec-audio.inc.pl |  5 +++++
 codec-image.inc.pl |  9 +++++++++
 codec.plp          | 16 +++++++++++-----
 3 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/codec-audio.inc.pl b/codec-audio.inc.pl
index 5bd336d..4d14f9b 100644
--- a/codec-audio.inc.pl
+++ b/codec-audio.inc.pl
@@ -4,22 +4,27 @@ codec => {
 	mp3 => {
 		name => '<abbr title="MPEG-1 Audio Layer III">MP3</abbr>',
 		available => 1991,
+		generation => 0,
 	},
 	vorbis => {
 		name => 'Vorbis',
 		available => 2000,
+		generation => 1,
 	},
 	opus => {
 		name => 'Opus',
 		available => 2012,
+		generation => 1,
 	},
 	aac => {
 		name => '<abbr title="Advanced Audio Coding">AAC</abbr>',
 		available => 1997,
+		generation => 1,
 	},
 	atrac => {
 		name => '<abbr title="Adaptive Transform Acoustic Coding">ATRAC</abbr>',
 		available => 1992,
+		generation => 0,
 	},
 },
 feature => {
diff --git a/codec-image.inc.pl b/codec-image.inc.pl
index 92e17d5..f9a544c 100644
--- a/codec-image.inc.pl
+++ b/codec-image.inc.pl
@@ -4,38 +4,47 @@ codec => {
 	jpeg => {
 		name => '<abbr title="Joint Photographic Experts Group">JPEG</abbr>',
 		available => 1992,
+		generation => 0,
 	},
 	gif => {
 		name => '<abbr title="Graphics Interchange Format">GIF</abbr>',
 		available => 1987,
+		generation => 0,
 	},
 	png => {
 		name => '<abbr title="Portable Network Graphics">PNG</abbr>',
 		available => 1996,
+		generation => 1,
 	},
 	jp2k => {
 		name => 'JPEG 2000',
 		available => 2000,
+		generation => 1,
 	},
 	webp => {
 		name => 'WebP',
 		available => 2010,
+		generation => 1,
 	},
 	heic => {
 		name => '<abbr title="High Efficiency Image Container (HEVC in HEIF)">HEIC</abbr>',
 		available => 2015,
+		generation => 2,
 	},
 	avif => {
 		name => '<abbr title="AV1 Image File Format">AVIF</abbr>',
 		available => 2019,
+		generation => 2,
 	},
 	jxl => {
 		name => 'JPEG XL',
 		available => 2021,
+		generation => 2,
 	},
 	pnm => {
 		name => '<abbr title="Portable aNyMap">PNM</abbr>',
 		available => 1988,
+		generation => 0,
 	},
 },
 feature => {
diff --git a/codec.plp b/codec.plp
index b2c3407..4251df9 100644
--- a/codec.plp
+++ b/codec.plp
@@ -31,16 +31,22 @@ my %BOOLSCORE = (y => [5, '✔'], n => [1, '✘'], 0 => [0, 'n/a']);
 
 <div class="section">
 <table class="mapped">
-	<col><colgroup span=3><colgroup span=2><colgroup span=3>
-<thead><tr><th rowspan=2>feature
 <:
 my @codecs = sort {
 	$info->{codec}->{$a}->{available} <=> $info->{codec}->{$b}->{available}
 } keys $info->{codec}->%*;
+my @codeccols = @{$info->{codec}}{@codecs};
 
-print '<th>', $_->{name} for @{$info->{codec}}{@codecs};
-print "\n<tr>";
-print '<td>', $_->{available} for @{$info->{codec}}{@codecs};
+{
+	print '<col>';
+	my @spans;
+	$spans[ $_->{generation} ]++ for @codeccols;
+	print "<colgroup span=$_>" for @spans;
+}
+say '<thead><tr><th rowspan=2>';
+say "\t", '<th>', $_->{name} for @codeccols;
+print '<tr>';
+print '<td>', $_->{available} for @codeccols;
 say '</thead>';
 
 while (defined (my $feat = shift @feat)) {
-- 
2.30.0