** 属性値
[3] この属性の値は [CODE(SGML)[%[[Coords]]]] です。
[[SGML]] 的には [CODE(SGML)[[[CDATA]]]] です。
[4] この属性は省略可能です。
仕様書には明記されていませんが、 [CODE(HTMLe)[area]]
の場合 [CODE(HTMLa)[[[shape]]]] が [CODE(HTML)[[[default]]]]
以外なら必須、 [CODE(HTMLe)[a]] の場合 [CODE(HTML)[default]]
の場合と画像写像の領域にしない場合以外は必須と思われます。
(そうしなければ意味を成しません。)
** 歴史
*** 大域属性としての使用
[9] [[XHTML2]] では [CODE(HTMLa)@en[[[src]]]] の[[大域属性]]化に伴い
[CODE(HTMLa)@en[[[coords]]]] [[属性]]も[[大域属性]]となりました。
;; [CITE@en[- XHTML Attribute Collections]] ([TIME[2002-12-12 23:58:38 +09:00]] 版)
[10]
[PRE(HTML example code)[
The cool site!
]PRE]
;; >>9 仕様案より
** メモ
[5]
[CITE@en-us[coords Property (A, AREA)]] ([CODE[2007-05-02 10:44:26 +09:00]] 版)
([[名無しさん]])
[6]
>>5
> For [CODE(HTMLe)@en[[[a]]]] objects, you must set the value of this property before you can retrieve it. This satisfies the requirements of World Wide Web Consortium (W3C) Document Object Model (DOM) Level 1 World Wide Web link. The page author is responsible for implementing the functionality defined in HTML 4.0 World Wide Web link for [CODE(HTMLe)@en[[[a]]]] objects, if desired.
意味がわからない。
([[名無しさん]] [WEAK[2007-05-02 01:49:01 +00:00]])
[7]
[CITE[Re: Image maps: should we drop ?]] ([[Ian Hickson]] 著, [CODE[2007-08-06 21:22:19 +09:00]] 版)
> Regarding , I don't think it's used any more now than when I
decided not to include it in HTML5, so I'm still of the opinion that not
including it is a good thing.
[8] [CITE[The SMIL 3.0 Linking Modules]] ([TIME[2008-12-02 00:45:09 +09:00]] 版)
[[#comment]]
* メモ
[11] [CITE[''''''[''''''whatwg'''''']'''''' Image maps: should we drop ?]]
( ([TIME[2011-01-19 23:53:23 +09:00]] 版))
[12] [CITE@en[Revamp coords parsing to be more compatible and less insane · whatwg/html@ead6cfe]]
([TIME[2016-01-30 20:58:07 +09:00]] 版)
[FIG(quote)[
[FIGCAPTION[
[13] [CITE@en[Google Maps JavaScript API V3 Reference | Google Maps JavaScript API | Google Developers]]
( ([TIME[2016-06-01 10:39:27 +09:00]]))
]FIGCAPTION]
> Type: Array
> The format of this attribute depends on the value of the type and follows the w3 AREA coords specification found at http://www.w3.org/TR/REC-html40/struct/objects.html#adef-coords.
> The coords attribute is an array of integers that specify the pixel position of the shape relative to the top-left corner of the target image. The coordinates depend on the value of type as follows:
> - circle: coords is '''['''x1,y1,r''']''' where x1,y2 are the coordinates of the center of the circle, and r is the radius of the circle.
> - poly: coords is '''['''x1,y1,x2,y2...xn,yn''']''' where each x,y pair contains the coordinates of one vertex of the polygon.
> - rect: coords is '''['''x1,y1,x2,y2''']''' where x1,y1 are the coordinates of the upper-left corner of the rectangle and x2,y2 are the coordinates of the lower-right coordinates of the rectangle.
]FIG]
[14] [CITE@en[Editorial: always state invalid value default]]
([[GloverDonovan]]著, [TIME[2018-03-05 13:36:29 +09:00]])