928.txt

[8]
[[HTML]]の[DFN[[CODE(HTMLe)@en[[[canvas]]]][[要素]]]]は、[[Web応用]]が[[図形]]を描くことができる、[[解像度]]依存の[[ビットマップ]][RUBY[[[画布]]] [キャンバス]]です。[[グラフ]]、[[ゲーム]]その他の[[画像]]を[[実行時]]に描画することを想定しています。

* 仕様書

[REFS[
- [9] [[HTML 5]] <http://www.whatwg.org/specs/web-apps/current-work/#canvas>
-- [93] [CITE@en-GB-x-hixie[HTML Standard]] ([TIME[2015-01-16 08:47:54 +09:00]] 版) <https://html.spec.whatwg.org/#dom-canvas-getcontext>
]REFS]

* DOM インターフェイス

[95] [CODE(HTMLe)@en[[[canvas]]]] [[要素]]の[[要素インターフェイス]]は、
[DFN[[CODE(DOMi)@en[[[HTMLCanvasElement]]]]]] [[インターフェイス]]です。

[96] [CODE(DOMi)@en[[[HTMLCanvasElement]]]] は、
[CODE(DOMi)@en[[[HTMLElement]]]] を[[継承]]しています。

* 属性

[10] 次の[[内容属性]]があります。
[FIG(short list)[
- [[大域属性]]
- [CODE(HTMLa)@en[[[alt]]]]
- [CODE(HTMLa)@en[[[height]]]]
- [CODE(HTMLa)@en[[[width]]]]
- [CODE(HTMLa)@en[[[moz-opaque]]]]
]FIG]

[100] 次の [[IDL属性]]があります。
[FIG(short list)[
- [CODE(DOMa)@en[[[height]]]]
- [CODE(DOMa)@en[[[width]]]]
- [CODE(DOMa)@en[[[mozOpaque]]]]
]FIG]

* 内容と終了タグ

[6] '''終了タグ'''
当初 [[Safari]] の実装では[[強制空要素]]で、
[[終了タグ]]はありませんでしたが、 [[HTML 5]]
では[[終了タグ]]が存在し、[[内容]]は[[代替内容]]とされています。
[[Firefox]]、[[Opera]] もこれに従っています。

@@ [[Safari 2]] は??

[16] '''代替内容'''
[[著者]]は、[[画布]]と機能・目的が同じ代わりのものも用意するべきです。
その代替物は [CODE(HTMLe)@en[[[canvas]]]][[要素]]の[[内容]]とすることができます。

;; [[代替内容]]の[[レンダリング]]: >>17

[416] [[canvasフォールバック内容]]の項を参照。

[42]
[CITE[Working with the WebKit Nightly Builds]] <http://developer.apple.com/opensource/internet/nightlywebkit.html>
([[名無しさん]] [WEAK[2006-11-05 02:47:03 +00:00]])

[43]
[CITE[Surfin’ Safari - Blog Archive &#187; Understanding HTML, XML and XHTML]] <http://webkit.org/blog/?p=68>
([[名無しさん]])

[[#comment]]

* レンダリング

[17] '''代替内容'''
- [[視覚]][[媒体]]で[[スクリプト]]が有効なら、[[置換ブロック水準要素]]として[[レンダリング]]するべきです。[[内容]]は[[レンダリング]]しません。
- それ以外の場合は、通常の[[ブロック水準要素]]として[[内容]]も[[レンダリング]]するべきです。
- 前者から後者へ移す場合 (例えば対話的画面に表示した[[文書]]を[[印刷]]する場合)
は、元の[[画像]]と[[大きさ]]を持った[[置換ブロック水準要素]]として[[レンダリング]]するべきです。

;; [97] 当初の [[Apple]] の実装では [CODE(HTMLa)@en[[[alt]]]] [[属性]]が規定されていたようですが、
これが[[レンダリング]]に用いられていたのかは不明です。

[18] '''大きさと座標空間'''
- [[座標空間]]は、[CODE(HTMLa)@en[[[width]]]][[属性]]と[CODE(HTMLa)@en[[[height]]]][[属性]]によって大きさが決まります。[[既定値]]はそれぞれ[CODE(HTML)[300]]と[CODE(HTMLa)[150]]です。
- [[CSS]]で[[置換要素]]の[[大きさ]]として使われる[[内在次元]]の大きさは、[[座標空間]]の大きさに[[CSS]]の[[単位]][CODE(CSS)@en[[[px]]]]を付けた[[値]]となります。
- [[CSS]][[画布]]上の[CODE(HTMLe)@en[[[canvas]]]][[要素]]の大きさは、[[CSS]]の[[特性]]の指定と[[内在次元]]に基づいて決まります。[[座標空間]]の大きさと関係なく拡大・縮小できます。
- [[利用者エージェント]]が内部で保持するデータの大きさ([[解像度]])は、[[利用者エージェント]]の実装と[[媒体]]の性質で決めます。1つの[[CSS]][[画素]]が複数の[[装置]][[画素]]であらわされる[[媒体]]では、それ相応の細かさで記述されたデータを内部で持つことになります。

[19] [CODE(HTMLa)@en[[[width]]]][[属性]]と[CODE(HTMLa)@en[[[height]]]][[属性]]は[[動的]]に書き換えられますが、その場合[[画布]]は初期状態に再設定(描画内容は消去)されます。

[20] '''背景'''
初期状態では、[[背景]]は[[黒]]の[[透明]]([CODE(CSS)@en[[[rgba]](0, 0, 0, 0)]])になります。[[CSS]]の[[背景]]も、その更に後ろに通常通り[[レンダリング]]されます。

* レンダリング文脈

[98] 次の[RUBYB[[[レンダリング文脈]]]@en[rendering context]]があります。
[FIG(short list)[
- [CODE(HTML)@en[[[2d]]]]
- [CODE(HTML)@en[bitmaprenderer]]
- [CODE(HTML)@en[[[webgl]]]]
- [CODE(HTML)@en[[[experimental-webgl]]]]
- [CODE(HTML)@en[[[opera-3d]]]]
- [CODE(HTML)@en[[[moz-gles11]]]]
- [CODE(HTML)@en[[[moz-glweb20]]]]
]FIG]

;; [99] [CODE(HTML)@en[[[moz-3d]]]] はかつて [[HTML5]] で拡張例として示されていましたが、
規定も実装もされていません。

* [CODE(DOMi)@en[HTMLCanvasElement]] インターフェイス [CODE(DOMm)@en[getContext]] メソッド

[94] [CODE(DOMi)@en[[[HTMLCanvasElement]]]] [[インターフェイス]]の
[DFN[[CODE(DOMm)@en[[[getContext]]]]]] [[メソッド]]は、
[[レンダリング文脈]]オブジェクトを返します。

* 歴史

[11]
はじめ、 [[Apple]] が [[Safari]] に (主として [[Dashboard]]
のために) [CODE(HTMLe)@en[[[canvas]]]] を考案・実装しました。

[12]
[[WHATWG]] の [[Web Applications 1.0]] 作業原案 ([[HTML 5]])
ははやくから [CODE(HTMLe)@en[[[canvas]]]] を仕様に取り込んでいます。

[13]
[[Gecko]] 1.8 ([[Firefox]] 1.5 ([[Deer Park]] 2 以降))、 [[Opera 9]]
(Preview 1 以降) も相次いでこれを実装しました。

[312] [[HTML5]] の中ではじめて Status が「Implemented and widely deployed」 ([[勧告]]相当)
に到達しました。

;; 当時はまだ [[HTML4]] 以来の機能に status が設定されていませんでした。

[1]
''Hixie's Natural Log: Extending HTML'' <http://ln.hixie.ch/?start=1089635050&count=1>

[[Apple]] が導入した [[HTML]] の拡張、
[CODE(HTMLe)[canvas]] 要素型などを通した、 HTML の拡張についての考察。
([[名無しさん]] [WEAK[2004-08-23 06:30:29 +00:00]])

[2]
[CITE[mozillaZine 日本語版 - mozillaZine 和訳]] <http://ryuzi.dyndns.org/mozillazine/html/modules/news/article.php?storyid=1017>

[[Gecko]] が [CODE(HTMLe)[[[canvas]]]]
を実装。
([[名無しさん]] [WEAK[2005-04-23 01:01:00 +00:00]])

[3]
[CITE[Evil Thoughts: Canvas and XUL]] <http://pavlov.net/blog/archives/2005/04/canvas_and_xul.html>
([[名無しさん]] [WEAK[2005-04-23 01:02:46 +00:00]])

[4]
[CITE[Drawing Graphics with Canvas - Devmo Ja]] <http://developer.mozilla.org/ja/docs/Drawing_Graphics_with_Canvas>

[CITE@en[Category:HTML:Canvas - MDC]] 
<http://developer.mozilla.org/ja/docs/Category:HTML:Canvas>

[7]
[CITE[blogfour: <canvas> support for IE]] <http://www.beaufour.dk/blog-archives/2005/06/canvas_support.html>
([[名無しさん]] [WEAK[2005-08-23 00:25:26 +00:00]])

[14]
[CITE[ブラウザ上でお絵かき: Days on the Moon]] <http://nanto.asablo.jp/blog/2005/09/27/89628>
([[名無しさん]] [WEAK[2005-11-18 13:28:02 +00:00]])

[15]
[CITE[Bug 288714 - HTML canvas impl]] <https://bugzilla.mozilla.org/show_bug.cgi?id=288714>
([[名無しさん]])

[21]
[CITE[Emil’s Chronicle &#187; Canvas in IE]] <http://me.eae.net/archive/2005/12/29/canvas-in-ie/>

[[HTC]]による実装。
([[名無しさん]] [WEAK[2006-01-04 01:09:27 +00:00]])

[22]
[CITE[Canvascape - 3D walker]] <http://www.abrahamjoffe.com.au/ben/canvascape/index.htm>

[[3D]][[迷路]]すげー
([[名無しさん]] [WEAK[2006-01-31 07:04:19 +00:00]])

[24]
[CITE[canvas-developers : Canvas Developers]] <http://groups.yahoo.com/group/canvas-developers/>
([[名無しさん]] [WEAK[2006-03-28 00:10:11 +00:00]])

[25]
[CITE[Canvas:3D - MozillaWiki]] <http://wiki.mozilla.org/Canvas:3D>
([[名無しさん]] [WEAK[2006-03-28 00:11:18 +00:00]])

[26]
[CITE[Canvas:Text - MozillaWiki]] <http://wiki.mozilla.org/Canvas:Text>
([[名無しさん]] [WEAK[2006-03-28 00:14:20 +00:00]])

[27]
[CITE[XUL:Canvas Tag - MozillaWiki]] <http://wiki.mozilla.org/XUL:Canvas_Tag>
([[名無しさん]])

[28]
[CITE[Vladimir Vuki&#263;evi&#263; &#187; Canvas Future]] <http://blog.vlad1.com/archives/2006/03/03/95/>
([[名無しさん]] [WEAK[2006-03-28 00:17:12 +00:00]])

[29]
[CITE[The 'Opera-2dgame' Canvas Context - Web Applications Blog - by Web Applications]] <http://my.opera.com/WebApplications/blog/show.dml/200788>
([[名無しさん]] [WEAK[2006-03-31 02:15:54 +00:00]])

[30]
[CITE[ExplorerCanvas]] <http://excanvas.sourceforge.net/>
([[名無しさん]] [WEAK[2006-05-27 03:52:48 +00:00]])

[31]
[CITE[Canvas tutorial - MDC]] <http://developer.mozilla.org/en/docs/Canvas_tutorial>
([[名無しさん]] [WEAK[2006-05-27 03:53:13 +00:00]])

[32]
[CITE[SVG & Canvas: Graphics for the Web]] <http://people.mozilla.com/~vladimir/xtech2006/>
([[名無しさん]] [WEAK[2006-05-27 03:53:32 +00:00]])

[33]
[CITE[Taken SPC : カテゴリー : canvas]] <http://taken.s101.xrea.com/blog/category.php?k=canvas>
([[名無しさん]])

[34]
[CITE[SourceForge.jp: Project Info - WebGL]] <http://sourceforge.jp/projects/webgl/>
([[名無しさん]])

[35]
[CITE[Taken SPC : canvas 要素のサンプル]] <http://taken.s101.xrea.com/blog/var/canvas/>
([[名無しさん]])

[36]
[CITE[Canvas shell]] <http://mozilla.doslash.org/stuff/canvas/shell.html>
([[名無しさん]])

[37]
[CITE[Canvex - canvas-based FPS game]] <http://canvex.lazyilluminati.com/>
([[名無しさん]])

[38]
[CITE[Paintr 2.1 Beta]] <http://annevankesteren.nl/2006/08-paintr21>
([[名無しさん]] [WEAK[2006-08-29 23:31:25 +00:00]])

[39]
[CITE[Taken SPC : Mozilla が canvas3d を実装]] <http://taken.s101.xrea.com/blog/article.php?id=629>
([[名無しさん]] [WEAK[2006-09-10 03:51:46 +00:00]])

[40]
[CITE[Perf-o-matic]] <http://graphs.mozilla.org/>
([[名無しさん]] [WEAK[2006-09-25 23:25:53 +00:00]])

[41]
[CITE[New Canvas Script]] <http://abrahamjoffe.com.au/ben/opera_canvas_bugs/index.htm>
([[名無しさん]] [WEAK[2006-10-01 00:33:32 +00:00]])

[44]
[CITE[Graraph - mz.skr.jp]] <http://mz.skr.jp/graraph/>
([[名無しさん]])

[45]
[CITE[Rhino Canvas]] <http://rhino-canvas.sourceforge.net/www/drawstring.html>
([[名無しさん]] [WEAK[2006-11-14 00:07:56 +00:00]])

[46]
[CITE[Rhino Canvas]] <http://rhino-canvas.sourceforge.net/>
([[名無しさん]] [WEAK[2006-11-14 00:09:07 +00:00]])

[48]
[CITE@ja[Bug 5522 - '''['''canvas''']'''transform, setTransform の実装]] ([CODE[2007-02-05 08:56:08 +09:00]] 版) <http://bugzilla.mozilla.gr.jp/show_bug.cgi?id=5522>
([[名無しさん]] [WEAK[2007-02-04 23:59:39 +00:00]])

[49]
[CITE[Bug 365886 &#8211; Implement canvas transform() and setTransform()]] ([CODE[2007-02-05 08:58:17 +09:00]] 版) <https://bugzilla.mozilla.org/show_bug.cgi?id=365886>
([[名無しさん]] [WEAK[2007-02-05 00:00:54 +00:00]])

[50]
[CITE[Bug 365886 &#8211; Implement canvas transform() and setTransform()]] ([CODE[2007-02-05 08:58:17 +09:00]] 版) <https://bugzilla.mozilla.org/show_bug.cgi?id=365886>
([[名無しさん]] [WEAK[2007-02-05 00:01:15 +00:00]])

[51]
[CITE[X3D Community Blog: 3D capable <canvas> HTML Tag by Opera & Mozilla]] ([CODE[2007-02-10 18:45:10 +09:00]] 版) <http://www.web3d.org/community/blog/archives/2006/10/3d_capable_canvas_html_tag_by/>
([[名無しさん]])

[52]
[CITE[canvas 3D - Anne’s Weblog]] ([CODE[2006-05-21 17:08:54 +09:00]] 版) <http://annevankesteren.nl/2006/05/canvas-3d>
([[名無しさん]])

[53]
[CITE@en[Vector graphic animation with JavaScript | ara pehlivanian—Web Standards, Web Culture, Web Everything.&#8482;]] ([CODE[2007-02-24 16:11:17 +09:00]] 版) <http://arapehlivanian.com/2007/02/19/vector-graphic-animation-with-javascript/>
([[名無しさん]] [WEAK[2007-02-24 07:12:26 +00:00]])

[54]
[CITE@ja[地図とHTML Canvas - Torisugari の日記]] ([CODE[2007-03-07 13:38:22 +09:00]] 版) <http://slashdot.jp/~Torisugari/journal/395817?from=rss>
([[名無しさん]] [WEAK[2007-03-07 12:23:07 +00:00]])

[56]
[CITE[A blog? with Σαιτω - CANVAS - Apple が特許を主張]] ([CODE[2007-03-16 15:17:30 +09:00]] 版) <http://d.hatena.ne.jp/saiton/20070316/1174010163>
([[名無しさん]] [WEAK[2007-03-16 08:58:21 +00:00]])

[57]
[CITE@en[I see a shitstorm coming - Arve Bersvendsen]] ([CODE[2007-03-16 07:58:13 +09:00]] 版) <http://virtuelvis.com/archives/2007/03/shitstorm-coming>
([[名無しさん]] [WEAK[2007-03-16 09:04:31 +00:00]])

[58]
[CITE@en[I see a shitstorm coming - Arve Bersvendsen]] ([CODE[2007-03-16 07:58:13 +09:00]] 版) <http://virtuelvis.com/archives/2007/03/shitstorm-coming>
([[名無しさん]] [WEAK[2007-03-16 09:10:17 +00:00]])

[59]
[CITE@en[I see a shitstorm coming - Arve Bersvendsen]] ([CODE[2007-03-16 07:58:13 +09:00]] 版) <http://virtuelvis.com/archives/2007/03/shitstorm-coming>
([[名無しさん]] [WEAK[2007-03-16 09:12:09 +00:00]])

[60]
[CITE@ja[【レポート】JavaScript + Canvasでレイトレを! - "Flog.RayTracer Canvas"の使い心地 (MYCOMジャーナル)]] ([CODE[2007-03-21 12:27:55 +09:00]] 版) <http://journal.mycom.co.jp/articles/2007/03/19/flog/>
([[名無しさん]] [WEAK[2007-03-21 03:29:29 +00:00]])

[61]
[CITE[A blog? with Σαιτω - canvas のデモ]] ([CODE[2007-03-21 01:22:01 +09:00]] 版) <http://d.hatena.ne.jp/saiton/20070320/1174360479>
([[名無しさん]])

[62]
[CITE[Canvas Raytracer @ Flog]] ([CODE[2007-03-11 17:55:54 +09:00]] 版) <http://labs.flog.co.nz/raytracer/>
([[名無しさん]])

[63]
[CITE@ja[【レポート】Canvas 3D Renderer & 3D WalkerでHTML Canvasの実力を知る (MYCOMジャーナル)]] ([CODE[2007-03-21 12:29:14 +09:00]] 版) <http://journal.mycom.co.jp/articles/2007/03/06/canvas/>
([[名無しさん]])

[64]
[CITE[Canvas tests - index]] ([CODE[2007-03-26 07:06:38 +09:00]] 版) <http://canvex.lazyilluminati.com/tests/tests/>
([[名無しさん]] [WEAK[2007-03-28 07:04:07 +00:00]])

[65]
[CITE[Latest topics > 多数のHTML Canvasを使用する時の、反応速度向上テクニック - outsider reflex]] ([[Piro(SHIMODA Hiroshi)]] 著, [CODE[2007-04-04 08:43:36 +09:00]] 版) <http://piro.sakura.ne.jp/latest/blosxom/mozilla/xul/2007-04-03_tabcatalog.htm>
([[名無しさん]] [WEAK[2007-04-03 23:46:42 +00:00]])

[66]
[CITE[Racing]] ([CODE[2007-02-27 12:26:31 +09:00]] 版) <http://tapper-ware.net/canvas3d/>
([[名無しさん]] [WEAK[2007-04-12 12:56:42 +00:00]])

[67]
[CITE[canvas-developers : Message: Re: Apple is asserting it's IP rights over canvas - what does that mean for canv]] ([CODE[2007-04-14 10:10:04 +09:00]] 版) <http://tech.groups.yahoo.com/group/canvas-developers/message/371>
([[名無しさん]] [WEAK[2007-04-14 01:12:47 +00:00]])

[68]
[CITE@en[canvas Support in Opera]] ([CODE[2007-05-01 10:47:19 +09:00]] 版) <http://www.opera.com/docs/specs/canvas/>
([[名無しさん]] [WEAK[2007-05-01 02:01:58 +00:00]])

[69]
[CITE[ExplorerCanvas]] ([CODE[2006-03-31 09:37:29 +09:00]] 版) <http://excanvas.sourceforge.net/>
([[名無しさん]] [WEAK[2007-05-05 23:29:46 +00:00]])

[70]
[CITE@ja[グラフを描く(canvas編)]] ([CODE[2007-05-05 22:18:48 +09:00]] 版) <http://oku.edu.mie-u.ac.jp/~okumura/javascript/graph-canvas.html>
([[名無しさん]] [WEAK[2007-05-05 23:30:39 +00:00]])

[71]
[CITE@en[PlotKit - Javascript Chart Plotting | liquidx]] ([CODE[2007-05-07 20:26:05 +09:00]] 版) <http://www.liquidx.net/plotkit/>
([[名無しさん]] [WEAK[2007-05-07 11:33:48 +00:00]])

[73]
[CITE@en[CanvasPaint]] ([CODE[2007-05-12 19:23:02 +09:00]] 版) <http://canvaspaint.org/>
([[名無しさん]])

[74]
[CITE@ja[Taken SPC : canvas で描画を save/resotre する]] ([CODE[2007-06-02 22:14:44 +09:00]] 版) <http://taken.s101.xrea.com/blog/article.php?id=750>
([[名無しさん]] [WEAK[2007-06-02 13:16:28 +00:00]])

[75]
[CITE@ja[Taken SPC : canvas でドロップシャドウ]] ([CODE[2007-06-24 16:01:11 +09:00]] 版) <http://taken.s101.xrea.com/blog/article.php?id=759>
([[名無しさん]] [WEAK[2007-06-24 07:03:51 +00:00]])

[76] [[三次元図形]]への対応は2007年頃から検討されはじめ、実験的な実装を経て
[[WebGL]] となりました。

;; [[WebGL]] の項を参照。

[77]
[CITE[public-canvas-api@w3.org Mail Archives]] ([CODE[2008-03-12 12:36:01 +09:00]] 版) <http://lists.w3.org/Archives/Public/public-canvas-api/>
([[名無しさん]])

[78]
[CITE[Usemap and ismap for canvas tag]] ([[Greg Houston <gregory.houston@...>]] 著, [CODE[2008-03-03 22:54:14 +09:00]] 版) <http://permalink.gmane.org/gmane.org.w3c.whatwg.discuss/13426>
([[名無しさん]])

[79]
いつのまにか、[[HTML 5]] の [CODE(HTMLe)@en[[[canvas]]]] [[要素]]の[[章]]の状態が最高の
[Q@en[Implemented and widely deployed]] になってます。
(各 [[API]] の[[節]]にも個別に状態が設定されています。)
([[名無しさん]])

[81]
[CITE[Timepedia Chronoscope]] ([CODE[2008-09-13 14:10:54 +09:00]] 版) <http://timepedia.org/chronoscope/>
([[名無しさん]])

[82]
[CITE@ja[HTML Canvasの3D対応への道を探る:CodeZine]] ([CODE[2008-10-24 20:40:02 +09:00]] 版) <http://codezine.jp/article/detail/3113>

[301] [CITE[Canvas Tutorial - Introduction]] ([TIME[2008-11-26 06:21:48 +09:00]] 版) <http://billmill.org/static/canvastutorial/>

[47]
[CITE@ja[JavaScriptで図形を描くHTML要素「Canvas」の実例 - GIGAZINE]] ([CODE[2007-01-13 01:27:39 +09:00]] 版) <http://gigazine.net/index.php?/news/comments/20070111_canvas/>
([[名無しさん]] [WEAK[2007-01-12 17:02:04 +00:00]])

[72]
[CITE[]] ([CODE[2005-05-25 19:04:44 +09:00]] 版) <http://www.sylloge.com/5k/entries/232/domaze5k.htm>

[CODE(HTMLe)@en[[[canvas]]]] を使わないこれもこれですごい。
([[名無しさん]])

[80]
[CITE@en[Mootools Mocha UI]] ([CODE[2008-06-17 07:07:03 +09:00]] 版) <http://mochaui.com/demo/>

[302] [CITE[気がついたらドット打ってた。 - uupaaの開発日記]] ([TIME[2008-12-27 13:39:28 +09:00]] 版) <http://d.hatena.ne.jp/uupaa/20081208/1228744833>

[304] [CITE[Silverlight で HTML5::Canvas を実装した - uupaaの開発日記]] ([TIME[2008-12-27 14:53:09 +09:00]] 版) <http://d.hatena.ne.jp/uupaa/20081118/1226938498>

[303] [CITE[excanvas.js にさようなら。 - uupaaの開発日記]] ([TIME[2008-12-27 13:40:07 +09:00]] 版) <http://d.hatena.ne.jp/uupaa/20081206/1228494722>

[305] [CITE['''['''Think IT''']''' 第2回:HTML 5+JavaScriptでCanvasアプリを作る (1/3)]] ([TIME[2009-01-13 14:18:36 +09:00]] 版) <http://thinkit.jp/article/773/1/>

情報が古いので注意。

[306] [CITE@en[Canvas]] ([TIME[2009-01-17 17:53:01 +09:00]] 版) <http://suika.fam.cx/www/canvas/cis/cis>

デバッグ用。

[307] [CITE@ja[スラッシュドット・ジャパン | Mozillaプロジェクト、IE向けのCanvasプラグインを開発中]] ([TIME[2009-01-27 20:49:49 +09:00]] 版) <http://slashdot.jp/it/article.pl?sid=08/08/21/1023205>

[308] [CITE@en-us[Firefox 3.1 for developers - MDC]] ([TIME[2009-02-08 18:25:06 +09:00]] 版) <https://developer.mozilla.org/ja/Firefox_3.1_for_developers#.E6.96.B0.E3.81.97.E3.81.8F.E3.82.B5.E3.83.9D.E3.83.BC.E3.83.88.E3.81.95.E3.82.8C.E3.81.9F.E6.A9.9F.E8.83.BD_3>

>
:HTML 5 text API for canvas elements:    canvas 要素のための HTML 5 text API がサポートされました。 
:Shadow effects:    Canvas shadow effects がサポートされました。 
:-moz-opaque 属性:    -moz-opaque 属性が追加されました。これは canvas に半透明な要素があるかどうかを知らせます。canvas が半透明な要素がないことを知った場合、ペインティングパフォーマンスは最適化されます。 bug 430906  を参照してください。

[309] [CITE[2009-02-11 - 最速チュパカブラ研究会]] ([TIME[2009-02-17 10:44:07 +09:00]] 版) <http://d.hatena.ne.jp/gyuque/20090211#1234364019>

[310] [CITE@en[ISSUE-15 immediate-mode-graphics proposal carries over objections]] ([[Dan Connolly]] 著, [TIME[2007-12-07 07:06:09 +09:00]] 版) <http://lists.w3.org/Archives/Public/public-html/2007Dec/0094.html>

[311] [CITE[Opera で HTML5::Canvas の fillText() をサポートできないかな - latest log]] ([TIME[2009-05-02 17:25:49 +09:00]] 版) <http://d.hatena.ne.jp/uupaa/20090427/1240801352>

[313] [CITE[スクショ拡張と Canvas でお絵かきツール実装したよという話 - 8時40分が超えられない - subtech]]
([TIME[2009-09-18 08:09:02 +09:00]] 版)
<http://subtech.g.hatena.ne.jp/secondlife/20090917/1253176532>

[314] [CITE[Firefoxではcanvasとsvgの両方に対応していますが、なぜ両方とも実装されたのでしょうか。また、canvasとsvgを比較したときのそれぞれのメリットとデメリットを詳しく教え.. - 人力検索はてな]]
([TIME[2009-09-19 17:21:23 +09:00]] 版)
<http://q.hatena.ne.jp/1187281995>

[315] [CITE@en[(X)HTML5 Tracking]]
([TIME[2009-09-22 01:01:34 +09:00]] 版)
<http://html5.org/tools/web-apps-tracker?from=3927&to=3928>

[316] [CITE@en[The Canvas 2D API 1.0 Specification]]
([TIME[2009-08-18 02:04:06 +09:00]] 版)
<http://dev.w3.org/html5/canvas-api/canvas-2d-api.html>

[317] [CITE[MicrosoftがHTML5からcanvas 2Dの仕様からの分離を提案。 - k3akinoriのWebデザインの日々日記]]
([TIME[2009-10-25 18:22:07 +09:00]] 版)
<http://d.hatena.ne.jp/k3akinori/20091024/1256404123>

[318] [CITE@en[Microsoft Wants to Separate the Canvas 2D API from HTML5 - Webmonkey]]
([[user generated]] 著, [TIME[2009-10-25 18:24:17 +09:00]] 版)
<http://www.webmonkey.com/blog/Microsoft_Wants_to_Separate_the_Canvas_2D_API_from_HTML5>

[319] [CITE@en[Ajaxian » Microsoft to help move Canvas 2D API out of HTML5 spec?]]
([TIME[2009-10-25 18:24:13 +09:00]] 版)
<http://ajaxian.com/archives/microsoft-to-help-move-canvas-2d-api-out-of-html5-spec>

[320] [CITE@en[Separate Draft of Canvas API Uploaded to CVS]]
([[Doug Schepers]] 著, [TIME[2009-08-18 02:49:20 +09:00]] 版)
<http://lists.w3.org/Archives/Public/public-canvas-api/2009JulSep/0002.html>

[321] [CITE@en[Re: Separate Draft of Canvas API Uploaded to CVS]]
([[Maciej Stachowiak]] 著, [TIME[2009-08-18 06:28:14 +09:00]] 版)
<http://lists.w3.org/Archives/Public/public-canvas-api/2009JulSep/0007.html>

[322] [CITE@en[Normative Dependency and the Seven Drafts (was: Canvas API Editors)]]
([[Doug Schepers]] 著, [TIME[2009-08-18 12:46:37 +09:00]] 版)
<http://lists.w3.org/Archives/Public/public-canvas-api/2009JulSep/0015.html>

[323] [CITE@en[Minutes: HTML Canvas Accessibility Meeting August 21, 2009]]
([[Richard Schwerdtfeger]] 著, [TIME[2009-08-22 04:51:02 +09:00]] 版)
<http://lists.w3.org/Archives/Public/public-canvas-api/2009JulSep/0026.html>

[324] [CITE@en[Minutes: Canvas Accessibility Call August 28, 2009]]
([[Richard Schwerdtfeger]] 著, [TIME[2009-08-29 03:53:05 +09:00]] 版)
<http://lists.w3.org/Archives/Public/public-canvas-api/2009JulSep/0054.html>

[325] [CITE@en[Re: Canvas 2D API specification update - defining the element or not]]
([[Maciej Stachowiak]] 著, [TIME[2009-10-22 07:25:16 +09:00]] 版)
<http://lists.w3.org/Archives/Public/public-canvas-api/2009OctDec/0005.html>

[326] [CITE@en[Re: Canvas 2D API specification update - defining the element or   not]]
([[Philip Taylor]] 著, [TIME[2009-10-23 21:55:20 +09:00]] 版)
<http://lists.w3.org/Archives/Public/public-canvas-api/2009OctDec/0011.html>

[327] [CITE@en[Re: Canvas 2D API specification update - defining the element or not]] ([[Shelley Powers]] 著, [TIME[2009-10-24 00:15:27 +09:00]] 版) <http://lists.w3.org/Archives/Public/public-canvas-api/2009OctDec/0015.html>

>The additional work to ensure the split
happens cleanly probably won't take more (as has been estimated) 8-10
hours.

こいつなめまくってるなwwwwwwwwwwwwwwwwwwwwwwwwwwww

[328] [CITE@en[RE: Canvas 2D API specification update - defining the element or not]]
([[Adrian Bateman]] 著, [TIME[2009-10-23 04:58:55 +09:00]] 版)
<http://lists.w3.org/Archives/Public/public-canvas-api/2009OctDec/0008.html>

[329] [CITE@en[RE: Canvas 2D API specification update - defining the element or not]]
([[Adrian Bateman]] 著, [TIME[2009-10-22 05:05:01 +09:00]] 版)
<http://lists.w3.org/Archives/Public/public-canvas-api/2009OctDec/0003.html>

[330] [CITE@en[<canvas> and the 2D context API (was RE: Begin discussions for  pushing Last Call into 2010)]]
([[Adrian Bateman]] 著, [TIME[2009-08-13 09:09:56 +09:00]] 版)
<http://lists.w3.org/Archives/Public/public-html/2009Aug/0628.html>

[331] [CITE@en[The Canvas 2D API 1.0 Specification]]
([TIME[2009-08-17 16:08:27 +09:00]] 版)
<http://dev.w3.org/cvsweb/~checkout~/2006/canvas-api/canvas-2d-api.html?rev=1.1&content-type=text/html;%20charset=utf-8>

[332] [CITE@en[The Canvas 2D API 1.0 Specification]]
([TIME[2009-10-22 06:27:06 +09:00]] 版)
<http://dev.w3.org/cvsweb/~checkout~/html5/canvas-api/canvas-2d-api.html?content-type=text/html;%20charset=utf-8>

[333] [CITE@ja[マイクロソフトがHTML5仕様からCanvas要素を外すように提案、しかし一刀両断に... - Publickey]]
([TIME[2009-10-27 22:29:10 +09:00]] 版)
<http://www.publickey.jp/blog/09/html5canvas.html>

[334] [CITE@en[Re: Canvas 2D API specification update]]
([[Ian Hickson]] 著, [TIME[2009-10-22 17:25:17 +09:00]] 版)
<http://lists.w3.org/Archives/Public/public-html/2009Oct/0782.html>

[335] [CITE@en[Re: Canvas 2D API specification update]]
([[Maciej Stachowiak]] 著, [TIME[2009-10-22 07:52:26 +09:00]] 版)
<http://lists.w3.org/Archives/Public/public-html/2009Oct/0756.html>

[336] [CITE@en[Separate Draft of Canvas API Uploaded to CVS]] ([[Doug Schepers]] 著, [TIME[2009-08-18 02:49:20 +09:00]] 版) <http://lists.w3.org/Archives/Public/public-canvas-api/2009JulSep/0002.html>

[337] [CITE[IRC logs: freenode / #whatwg / 20091024]]
([TIME[2009-12-13 10:08:59 +09:00]] 版)
<http://krijnhoetmer.nl/irc-logs/whatwg/20091024#l-260>

[338] [CITE@en[(X)HTML5 Tracking]]
([TIME[2010-01-05 15:47:52 +09:00]] 版)
<http://html5.org/tools/web-apps-tracker?from=4464&to=4465>

[339] [CITE@en[(X)HTML5 Tracking]]
([TIME[2010-01-09 14:11:10 +09:00]] 版)
<http://html5.org/tools/web-apps-tracker?from=4543&to=4544>

[340] [CITE@en-US-x-Hixie[HTML5 2D Context]]
([TIME[2010-01-09 10:10:49 +09:00]] 版)
<http://dev.w3.org/html5/2dcontext/Overview.html>

[341] [CITE[IRC logs: freenode / #whatwg / 20100503]]
([TIME[2010-05-31 06:35:58 +09:00]] 版)
<http://krijnhoetmer.nl/irc-logs/whatwg/20100503#l-299>

[342] [CITE@en[HTML Accessibility Task Force Teleconference -- 03 May 2010]]
([TIME[2010-05-04 04:31:21 +09:00]] 版)
<http://www.w3.org/2010/05/03-html-a11y-minutes.html>

[343] [CITE[IRC logs: freenode / #whatwg / 20100715]]
([TIME[2010-08-03 08:03:40 +09:00]] 版)
<http://krijnhoetmer.nl/irc-logs/whatwg/20100715>

[101] 2010年8月には、それまで [[WHATWG Wiki]] [SRC[>>85]]
を参照する形になっていた[[レンダリング文脈]]
([CODE(DOMm)@en[[[getContext]]]] [[メソッド]]の[[引数]]) を、挙動をより厳密に規定するため
[[HTML5]] 本体で直接定義する形に改めました [SRC[>>84]]。

[103] なお [[W3C]] [[HTML 5.0]] はすぐには追随しませんでした [SRC[>>85]] が、
結局は [[WHATWG]] 版と同じ形になっています [SRC[>>102]]。しかし [[WHATWG]]
版をそのまま採用せず独自に編集しているためか、[[参考]]として古い [[WHATWG Wiki]]
のページへのリンクが [[W3C勧告]]版に至ってもなお残っています [SRC[>>102]]。

;; [104] [[W3C]] ではよくあることなので、深く気にすることではなさそうです。

[REFS[
- [84] [CITE@en[Web Applications 1.0 r5227  Redefine getContext() so that the handling of multple context types is defined.]] ([TIME[2010-08-03 07:16:00 +09:00]] 版) <https://html5.org/r/5227>
- [85] [CITE@en[CanvasContexts - WHATWG Wiki]]
([TIME[2010-08-03 07:03:28 +09:00]] 版)
<http://wiki.whatwg.org/wiki/CanvasContexts>
- [102] [CITE@en-US-x-Hixie[HTML5]] ([TIME[2014-10-25 01:15:24 +09:00]] 版) <http://www.w3.org/TR/2014/REC-html5-20141028/single-page.html#the-canvas-element>
]REFS]

[344] [CITE['''['''whatwg''']''' Canvas feedback (various threads)]]
([TIME[2010-08-12 07:52:32 +09:00]] 版)
<http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2010-August/027879.html>

[345] [CITE@en-US-x-Hixie[HTML Canvas 2D Context]]
( ([TIME[2010-10-20 12:15:06 +09:00]] 版))
<http://www.w3.org/TR/2010/WD-2dcontext-20101019/>

[346] [CITE['''['''whatwg''']''' Canvas feedback (various threads)]]
([TIME[2010-11-16 17:09:14 +09:00]] 版)
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2010-November/029043.html>

[347] [CITE[''''''[''''''whatwg'''''']'''''' Attitude and Direction of the WHATWG]]
( ([TIME[2010-11-27 20:19:46 +09:00]] 版))
<http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2010-November/029198.html>

[348] [CITE[スマートフォンのcanvasタグのバグのまとめ - yukobaのブログ]]
([TIME[2010-12-12 13:14:54 +09:00]] 版)
<http://d.hatena.ne.jp/yukoba/20100322/p1>

[349] [CITE@en-US-x-Hixie[HTML Canvas 2D Context]]
( ([TIME[2011-01-15 03:48:13 +09:00]] 版))
<http://www.w3.org/TR/2011/WD-2dcontext-20110113/>

[350] [CITE[The whatwg April 2005 Archive by thread]]
( ([TIME[2011-01-19 23:27:11 +09:00]] 版))
<http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2005-April/thread.html>

[351] [CITE[CANVAS element in Mozilla — Anne’s Blog]]
( ([TIME[2011-01-19 23:54:29 +09:00]] 版))
<http://annevankesteren.nl/2005/04/canvas-element>

[352] [CITE@en[Web Applications 1.0 r5873     Make sure cross-origin fonts can't leak data via <canvas>.]]
( ([TIME[2011-02-11 10:48:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=5872&to=5873>

[353] [CITE[''''''[''''''whatwg'''''']'''''' Canvas feedback (various threads)]]
( ([TIME[2011-02-11 11:31:59 +09:00]] 版))
<http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2011-February/030381.html>

[354] [CITE@en-US-x-Hixie[HTML Canvas 2D Context]]
( ([TIME[2011-04-06 00:16:27 +09:00]] 版))
<http://www.w3.org/TR/2011/WD-2dcontext-20110405/>

[355] [CITE@en[Bug 11239 proposed patch]]
( ([[Ian Hickson]] 著, [TIME[2011-04-28 12:26:21 +09:00]] 版))
<http://lists.w3.org/Archives/Public/public-html/2011Apr/0700.html>

[356] [CITE@en-US-x-Hixie[HTML Canvas 2D Context]]
( ([TIME[2011-05-26 05:55:12 +09:00]] 版))
<http://www.w3.org/TR/2011/WD-2dcontext-20110525/>

[357] [CITE@en[Web Applications 1.0 r6201 apply chair revert request]]
( ([TIME[2011-06-09 15:57:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=6200&to=6201>

[358] [CITE[Introduction – SVG 1.1 (Second Edition)]]
( ([TIME[2011-08-10 12:35:27 +09:00]] 版))
<http://www.w3.org/TR/2011/REC-SVG11-20110816/intro.html#TermCanvas>

[359] [CITE[IRC logs: freenode / #whatwg / 20111112]]
( ([TIME[2011-11-14 08:18:03 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20111112>

[360] [CITE[IRC logs: freenode / #whatwg / 20111208]]
( ([TIME[2011-12-10 00:35:44 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20111208>

[361] [CITE[''''''[''''''whatwg'''''']'''''' Canvas ScrollBar]]
( ([TIME[2012-01-28 11:22:18 +09:00]] 版))
<http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2012-January/034555.html>

[362] [CITE@en[Web Applications 1.0 r7011 Update notes in canvas source regarding upcoming new features.]]
( ([TIME[2012-03-01 08:39:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=7010&to=7011>

[363] [CITE@en[Canvas - WHATWG Wiki]]
( ([TIME[2012-03-03 08:48:23 +09:00]] 版))
<http://wiki.whatwg.org/wiki/Canvas>

[364] [CITE[IRC logs: freenode / #whatwg / 20120228]]
( ([TIME[2012-03-08 00:01:17 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20120228>

[365] [CITE[IRC logs: freenode / #whatwg / 20120301]]
( ([TIME[2012-03-08 21:48:13 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20120301>

[366] [CITE@en[Web Applications 1.0 r7023     Path objects and drawing text to a path or along a path. Note that there's not yet any way to _use_ the Path objects. That's next...]]
( ([TIME[2012-03-10 08:58:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=7022&to=7023>

[367] [CITE@en[Web Applications 1.0 r7024     Make it possible to draw Path primitives to the canvas.]]
( ([TIME[2012-03-10 09:31:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=7023&to=7024>

[368] [CITE[IRC logs: freenode / #whatwg / 20120306]]
( ([TIME[2012-03-11 20:49:03 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20120306>

[369] [CITE@en[Web Applications 1.0 r7025     Add ellipse support to canvas.]]
( ([TIME[2012-03-14 04:33:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=7024&to=7025>

[370] [CITE@en[Web Applications 1.0 r7026     Add SVG paths to Path objects in canvas.]]
( ([TIME[2012-03-14 07:46:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=7025&to=7026>

[371] [CITE@en[Web Applications 1.0 r7028     add dashed lines and change how Path objects work to instead use external line and font styles and transformation objects]]
( ([TIME[2012-03-20 07:29:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=7027&to=7028>

[372] [CITE[IRC logs: freenode / #whatwg / 20120314]]
( ([TIME[2012-03-18 01:33:50 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20120314>

[373] [CITE[IRC logs: freenode / #whatwg / 20120315]]
( ([TIME[2012-03-21 08:57:20 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20120315#l-988>

[374] [CITE@en[Web Applications 1.0 r7029     Make it easier to do hit testing on canvas]]
( ([TIME[2012-03-26 14:11:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=7028&to=7029>

[375] [CITE@en[Web Applications 1.0 r7030     Pattern transforms, first draft]]
( ([TIME[2012-03-27 07:57:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=7029&to=7030>

[376] [CITE[''''''[''''''whatwg'''''']'''''' Canvas v5 API additions]]
( ([TIME[2012-03-29 07:54:46 +09:00]] 版))
<http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2012-March/035239.html>

[377] [CITE@en-US-x-Hixie[HTML Canvas 2D Context]]
( ([TIME[2012-03-30 02:48:04 +09:00]] 版))
<http://www.w3.org/TR/2012/WD-2dcontext-20120329/>

[378] [CITE[IRC logs: freenode / #whatwg / 20120328]]
( ([TIME[2012-04-09 21:56:14 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20120328>

[379] [CITE[IRC logs: freenode / #whatwg / 20120328]]
( ([TIME[2012-04-09 21:56:14 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20120328#l-991>

[380] [CITE[''''''[''''''whatwg'''''']'''''' Canvas v5 API additions]]
( ([TIME[2012-06-23 08:56:39 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2012-June/036475.html>

[381] [CITE@en[Web Applications 1.0 r7178     Try to introduce 'HD' versions of the ImageData API. PLEASE DO NOT IMPLEMENT THESE IF YOU DO NOT HAVE VARIABLE-RESOLUTION CANVASES.]]
( ([TIME[2012-07-17 16:45:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=7177&to=7178>

[382] [CITE@en[Editorial team for Canvas 2D Context]]
( ([[Paul Cotton]] 著, [TIME[2012-08-03 02:28:48 +09:00]] 版))
<http://lists.w3.org/Archives/Public/public-html/2012Aug/0060.html>

[383] [CITE[''''''[''''''whatwg'''''']'''''' Canvas roundedRect]]
( ([TIME[2012-09-04 00:08:43 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2012-September/037109.html>

[384] [CITE[''''''[''''''whatwg'''''']'''''' <canvas> and high-density displays]]
( ([TIME[2012-09-25 00:42:04 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2012-September/037406.html>

[385] [CITE[''''''[''''''whatwg'''''']'''''' Blending, filtering]]
( ([TIME[2012-09-26 06:11:22 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2012-September/037432.html>

[386] [CITE[IRC logs: freenode / #whatwg / 20120925]]
( ([TIME[2012-09-29 18:41:27 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20120925>

[387] [CITE@en-US-x-Hixie[HTML Canvas 2D Context]]
( ([TIME[2012-10-25 03:34:00 +09:00]] 版))
<http://www.w3.org/TR/2012/WD-2dcontext-20121025/>

[388] [CITE[''''''[''''''whatwg'''''']'''''' Canvas in Workers]]
( ([TIME[2012-11-17 11:03:16 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2012-November/037965.html>

[389] [CITE@en[Web Applications 1.0 r7509      First draft of a way to do canvas in workers.]]
( ([TIME[2012-11-17 05:26:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=7508&to=7509>

[390] [CITE[''''''[''''''whatwg'''''']'''''' '''['''canvas''']''' inner shadows]]
( ([TIME[2012-11-24 08:38:45 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2012-November/038079.html>

[391] [CITE[''''''[''''''whatwg'''''']'''''' <canvas> and high-density displays]]
( ([TIME[2012-11-24 08:04:14 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2012-November/038078.html>

[392] [CITE[IRC logs: freenode / #whatwg / 20121106]]
( ([TIME[2012-11-25 00:23:33 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20121106#l-939>

[393] [CITE@en-US-x-Hixie[HTML Canvas 2D Context]]
( ([TIME[2012-11-02 22:15:54 +09:00]] 版))
<http://htmlwg.org/cr/2dcontext/Overview.html>

[394] [CITE[''''''[''''''whatwg'''''']'''''' Canvas-related feedback]]
( ([TIME[2012-12-18 05:57:51 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2012-December/038380.html>

[395] [CITE@en-US-x-Hixie[HTML Canvas 2D Context]]
( ([TIME[2012-12-13 00:03:03 +09:00]] 版))
<http://www.w3.org/TR/2012/CR-2dcontext-20121217/>

[396] [CITE@en-US-x-Hixie[HTML Canvas 2D Context, Level 2]]
( ([TIME[2012-12-15 06:34:31 +09:00]] 版))
<http://www.w3.org/TR/2012/WD-2dcontext2-20121217/>

[397] [CITE[''''''[''''''whatwg'''''']'''''' Proposal: Add CanvasRenderingContext2D.fillRule with "nonzero" (default) and "evenodd" options]]
( ([TIME[2013-01-04 09:44:11 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2013-January/038503.html>

[398] [CITE[''''''[''''''whatwg'''''']'''''' Canvas in Workers]]
( ([TIME[2013-01-08 19:30:37 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2013-January/038556.html>

[399] [CITE@en[Web Applications 1.0 r7853     Try to match reality, and adapt not-yet-implemented features to match.]]
( ([TIME[2013-04-26 09:23:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=7852&to=7853>

[400] [CITE@en-US-x-Hixie[HTML Canvas 2D Context, Level 2]]
( ([TIME[2013-06-04 19:48:08 +09:00]] 版))
<http://www.w3.org/TR/2013/WD-2dcontext2-20130528/>

[401] [CITE[''''''[''''''whatwg'''''']'''''' Adding 2D Canvas features (Was: Grouping in canvas 2d)]]
( ([TIME[2013-06-15 02:42:44 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2013-June/039745.html>

[402] [CITE[''''''[''''''whatwg'''''']'''''' Enabling LCD Text and antialiasing in canvas]]
( ([TIME[2013-07-16 22:41:49 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2013-July/040103.html>

[403] [CITE[IRC logs: freenode / #whatwg / 20130718]]
( ([TIME[2013-07-20 20:33:23 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20130718#l-585>

[404] [CITE[''''''[''''''whatwg'''''']'''''' High-density canvases]]
( ([TIME[2013-09-10 00:07:53 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2013-September/040735.html>

[405] [CITE[IRC logs: freenode / #whatwg / 20130930]]
( ([TIME[2013-10-02 09:02:45 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20130930>

[406] [CITE[IRC logs: freenode / #whatwg / 20130930]]
( ([TIME[2013-10-02 09:02:45 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20130930>

[407] [CITE@en[Bug 23515 – <canvas>: opaque backing stores]]
( ([TIME[2013-10-14 22:59:01 +09:00]] 版))
<https://www.w3.org/Bugs/Public/show_bug.cgi?id=23515>

[408] [CITE@en[Bug 23514 – Manual memory management for image assets used in canvas games]]
( ([TIME[2013-10-14 22:59:18 +09:00]] 版))
<https://www.w3.org/Bugs/Public/show_bug.cgi?id=23514>

[409] [CITE@en[Bug 23510 – <canvas>: Allow EXIF data to be passed to toBlob()]]
( ([TIME[2013-10-14 22:59:28 +09:00]] 版))
<https://www.w3.org/Bugs/Public/show_bug.cgi?id=23510>

[410] [CITE@en[Bug 23516 – <canvas>: controlling whether text is anti-aliased]]
( ([TIME[2013-10-14 22:59:59 +09:00]] 版))
<https://www.w3.org/Bugs/Public/show_bug.cgi?id=23516>

[411] [CITE@en[Canvas Context Loss and Restoration - WHATWG Wiki]]
( ([TIME[2013-10-21 15:37:18 +09:00]] 版))
<http://wiki.whatwg.org/wiki/Canvas_Context_Loss_and_Restoration>

[412] [CITE@en-US-x-Hixie[HTML Canvas 2D Context, Level 2]]
( ([TIME[2013-10-30 01:02:02 +09:00]] 版))
<http://www.w3.org/TR/2013/WD-2dcontext2-20131029/>

[413] [CITE@en[709490 – Run WebGL on Web Worker with Off-Main-Thread-Compositing]]
( ([TIME[2013-11-26 21:08:28 +09:00]] 版))
<https://bugzilla.mozilla.org/show_bug.cgi?id=709490>

[414] [CITE[''''''[''''''whatwg'''''']'''''' hit regions: limited set of elements for fallback content]]
( ([TIME[2014-02-18 21:44:10 +09:00]] 版))
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2014-February/042031.html>

[415] [CITE[IRC logs: freenode / #whatwg / 20140312]]
( ([TIME[2014-03-13 21:49:14 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20140312>

[417] ( ([TIME[2014-04-11 22:37:43 +09:00]] 版))
<http://damowmow.com/temp/canvas-specs>

[86] [CITE[''''''[''''''whatwg'''''']'''''' Canvas.getContext error handling]]
( ([TIME[2011-04-13 08:37:48 +09:00]] 版))
<http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2011-April/031192.html>

[87] [CITE[IRC logs: freenode / #whatwg / 20110413]]
( ([TIME[2011-04-16 20:17:13 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20110413>

[88] [CITE['''['''whatwg''']''' Canvas.getContext error handling]]
([TIME[2011-05-13 13:47:03 +09:00]] 版)
<http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2011-May/031553.html>

[89] [CITE@en[Web Applications 1.0 r6130 Mention the case of getContext('webgl') returning null due to hardware limitations.]]
( ([TIME[2011-05-12 15:58:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=6129&to=6130>

[90] [CITE[IRC logs: freenode / #whatwg / 20121110]]
( ([TIME[2012-11-28 01:01:44 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20121110#l-411>

[91] [CITE[Well, I'm Back: The Canvas getContext() Mistake]]
( ([TIME[2014-08-18 23:06:08 +09:00]] 版))
<http://robert.ocallahan.org/2012/05/canvas-getcontext-mistake.html>

[92] [CITE@en[Web Applications 1.0 r8755     Define getContext('2d', {alpha:false}).]]
( ([TIME[2014-09-09 07:53:00 +09:00]] 版))
<http://html5.org/r/8755>

* メモ

[18] '''他に適当な要素型がないか'''
他に適当な[[要素型]]があるときに[CODE(HTMLe)@en[[[canbas]]]]を使うのは不適切です。例えば、[[見出し]]を凝った装飾付き文字にしたい時は、[CODE(HTMLe)@en[[[h1]]]]で[[マーク付け]]し、装飾は[[CSS]]と[[XBL]]で行うべきです。

[5] '''[CODE(HTMLe)@en[canvas]] vs SVG'''
,	,[CODE(HTMLe)@en[canvas]] ([CODE(HTML)@en[[[2d]]]])	,[[SVG]]
,記述方法	,[[スクリプト]]で[[手続き的]]	,[[XML]] で[[宣言的]]
,文字列の描画	,×	,○
,動的な変更	,○ ([[スクリプト]])	,"○ ([[スクリプト]], [[アニメーション]])"
,描画の [[DOM]] への反映	,×	,○
,[[CSS]]	,×	,○
,[[HTML]] に埋込み	,○ ([CODE(HTMLe)@en[canvas]] + [CODE(HTMLe)@en[[[script]]]])	,×
,[[XHTML]] に埋込み	,○ ([CODE(HTMLe)@en[canvas]] + [CODE(HTMLe)@en[[[script]]]])	,○ ([CODE(XMLe)@en[[[svg]]]])
,[[HTML]] から参照	,○ ([CODE(HTMLe)@en[canvas]] + [CODE(HTMLe)@en[[[script]]]] [CODE(HTMLa)@en[[[src]]]])	,○ ([CODE(HTMLe)@en[[[object]]]])
,[[XHTML]] から参照	,○ ([CODE(HTMLe)@en[canvas]] + [CODE(HTMLe)@en[[[script]]]] [CODE(HTMLa)@en[[[src]]]])	,○ ([CODE(HTMLe)@en[[[object]]]])
,[[ラスタ画像]]データに変換	,○ ([CODE(DOMm)@en[[[toDataURL]]]])	,△
,標準化団体	,[[WHATWG]]	,[[W3C]] [[SVG WG]]
,[[Mozilla Firefox]]	,1.5 Alpha 2 以降	,1.5 Alpha 2 以降 (一部のみ)
,[[Safari]]	,○	,○
,[[Opera]]	,9.0 Preview 1 以降	,8 以降 ([[SVG Tiny]])
,[[携帯電話]]	,×	,○ ([[SVG Tiny]])

[23]
[[SVG]]より[CODE(HTMLa)@en[[[canvas]]]]の方がよさそうなもの:
- [[手書き入力]]の描画部
- [[モンテカルロ法]]の図示
- [[速度]]が求められる[[ゲーム]]

[55]
[CITE[Christian Simms’s Weblog &#187; Blog Archive &#187; SVG vs. Canvas: Tastes Great, or Less Filling?]] ([CODE[2007-03-15 09:20:22 +09:00]] 版) <http://csimms.botonomy.com/2006/02/12/svg-vs-canvas-tastes-great-or-less-filling/>


[83] [CITE@en[60fps on the mobile web — Flipboard Engineering]]
([TIME[2015-02-12 04:35:50 +09:00]] 版)
<http://engineering.flipboard.com/2015/02/mobile-web/>

[105] [CITE@en[Re: ''''''[''''''whatwg'''''']'''''' Canvas image to blob/dataurl within Worker]]
([[Kenneth Russell]] 著, [TIME[2015-04-08 08:41:01 +09:00]] 版)
<https://lists.w3.org/Archives/Public/public-whatwg-archive/2015Apr/0050.html>

[106] [CITE@en[''''''[''''''embedded'''''']'''''' As discussed during the Paris F2F, rewrite the use of HTML5 · w3c/svgwg@bda84ee]]
([TIME[2015-09-02 11:23:17 +09:00]] 版)
<https://github.com/w3c/svgwg/commit/bda84ee3ce02bdf810a7feeecd9f31f5634e39b9>

[107] [CITE@en[Fix #345: Remove table sorting model · whatwg/html@59b7e24]]
([TIME[2016-01-29 23:29:27 +09:00]] 版)
<https://github.com/whatwg/html/commit/59b7e2466c2b7c5c408a4963b05b13fd808aa07a>

[108] [CITE@en[Add new canvas rendering context: ImageBitmapRenderingContext · whatwg/html@4c59797]]
([TIME[2016-04-13 15:01:58 +09:00]] 版)
<https://github.com/whatwg/html/commit/4c59797403ca6545ca54ec2808264f5723727e7a>

[109] [CITE@en[<canvas> hit region API]]
([[Anne van Kesteren]] 著, [TIME[2016-04-18 23:24:05 +09:00]] 版)
<https://lists.w3.org/Archives/Public/www-archive/2016Apr/0000.html>

[110] [CITE@en[Remove old-fashioned vendor-specific extension advice]]
([[annevk]]著, [TIME[2016-10-13 02:28:15 +09:00]])
<https://github.com/whatwg/html/commit/76f88a4015d55273749c34238d250b7bdb1aff62>

[111] [CITE@en[Remove canvas element's hit region feature (for now)]]
([[annevk]]著, [TIME[2016-10-21 18:01:07 +09:00]])
<https://github.com/whatwg/html/commit/9d493a37ed7e49c58522a3fed05d14bde1a8913c>