map elementnameinterface HTMLMapElement : HTMLElement {
attribute DOMString name;
readonly attribute HTMLCollection areas;
readonly attribute HTMLCollection images;
};
The map element, in conjunction with any
area element descendants, defines an image
map. The element represents its children.
The name attribute
gives the map a name so that it can be referenced. The attribute
must be present and must have a non-empty value with no space characters. The value of the
name attribute must not be a
compatibility-caseless
match for the value of the name
attribute of another map element in the same
document. If the id attribute is also
specified, both attributes must have the same value.
areasReturns an HTMLCollection of the area elements in the map.
imagesReturns an HTMLCollection of the img and object elements that use the map.
Image maps can be defined in conjunction with other content on the page, to ease maintenance. This example is of a page with an image map at the top of the page and a corresponding set of text links at the bottom.
<!DOCTYPE HTML>
<TITLE>Babies™: Toys</TITLE>
<HEADER>
<H1>Toys</H1>
<IMG SRC="/images/menu.gif"
ALT="Babies™ navigation menu. Select a department to go to its page."
USEMAP="#NAV">
</HEADER>
...
<FOOTER>
<MAP NAME="NAV">
<P>
<A HREF="/clothes/">Clothes</A>
<AREA ALT="Clothes" COORDS="0,0,100,50" HREF="/clothes/"> |
<A HREF="/toys/">Toys</A>
<AREA ALT="Toys" COORDS="0,0,100,50" HREF="/toys/"> |
<A HREF="/food/">Food</A>
<AREA ALT="Food" COORDS="0,0,100,50" HREF="/food/"> |
<A HREF="/books/">Books</A>
<AREA ALT="Books" COORDS="0,0,100,50" HREF="/books/">
</MAP>
</FOOTER>
area elementmap element ancestor.altcoordsshapehreftargetrelmediahreflangtypeinterface HTMLAreaElement : HTMLElement {
attribute DOMString alt;
attribute DOMString coords;
attribute DOMString shape;
stringifier attribute DOMString href;
attribute DOMString target;
attribute DOMString rel;
readonly attribute DOMTokenList relList;
attribute DOMString media;
attribute DOMString hreflang;
attribute DOMString type;
// URL decomposition IDL attributes
attribute DOMString protocol;
attribute DOMString host;
attribute DOMString hostname;
attribute DOMString port;
attribute DOMString pathname;
attribute DOMString search;
attribute DOMString hash;
};
The area element represents either a
hyperlink with some text and a corresponding area on an image
map, or a dead area on an image map.
If the area element has an href attribute, then the
area element represents a hyperlink. In
this case, the alt
attribute must be present. It specifies the text of the
hyperlink. Its value must be text that, when presented with the
texts specified for the other hyperlinks of the image
map, and with the alternative text of the image, but without
the image itself, provides the user with the same kind of choice as
the hyperlink would when used without its text but with its shape
applied to the image. The alt
attribute may be left blank if there is another area
element in the same image map that points to the same
resource and has a non-blank alt
attribute.
If the area element has no href attribute, then the area
represented by the element cannot be selected, and the alt attribute must be omitted.
In both cases, the shape and
coords attributes specify the
area.
The shape
attribute is an enumerated attribute. The following
table lists the keywords defined for this attribute. The states
given in the first cell of the rows with keywords give the states to
which those keywords map.
| State | Keywords |
|---|---|
| Circle state | circle
|
| Default state | default
|
| Polygon state | poly
|
| Rectangle state | rect
|
The attribute may be omitted. The missing value default is the rectangle state.
The coords
attribute must, if specified, contain a valid list of
integers. This attribute gives the coordinates for the shape
described by the shape
attribute.
In the circle state,
area elements must have a coords attribute present, with three
integers, the last of which must be non-negative. The first integer
must be the distance in CSS pixels from the left edge of the image
to the center of the circle, the second integer must be the distance
in CSS pixels from the top edge of the image to the center of the
circle, and the third integer must be the radius of the circle,
again in CSS pixels.
In the default state
state, area elements must not have a coords attribute. (The area is the
whole image.)
In the polygon state,
area elements must have a coords attribute with at least six
integers, and the number of integers must be even. Each pair of
integers must represent a coordinate given as the distances from the
left and the top of the image in CSS pixels respectively, and all
the coordinates together must represent the points of the polygon,
in order.
In the rectangle state,
area elements must have a coords attribute with exactly four
integers, the first of which must be less than the third, and the
second of which must be less than the fourth. The four points must
represent, respectively, the distance from the left edge of the
image to the left side of the rectangle, the distance from the
top edge to the top side, the distance from the left edge to the
right side, and the distance from the top edge to the bottom side,
all in CSS pixels.
The target,
rel, media, hreflang, and type attributes must be omitted
if the href attribute is
not present.
An image map allows geometric areas on an image to be associated with hyperlinks.
An image, in the form of an img element or an
object element representing an image, may be associated
with an image map (in the form of a map element) by
specifying a usemap attribute on
the img or object element. The usemap attribute, if specified,
must be a valid hash-name reference to a
map element.
Consider an image that looks as follows:
If we wanted just the colored areas to be clickable, we could do it as follows:
<p>
Please select a shape:
<img src="shapes.png" usemap="#shapes"
alt="Four shapes are available: a red hollow box, a green circle, a blue triangle, and a yellow four-pointed star.">
<map name="shapes">
<area shape=rect coords="50,50,100,100"> <!-- the hole in the red box -->
<area shape=rect coords="25,25,125,125" href="red.html" alt="Red box.">
<area shape=circle coords="200,75,50" href="green.html" alt="Green circle.">
<area shape=poly coords="325,25,262,125,388,125" href="blue.html" alt="Blue triangle.">
<area shape=poly coords="450,25,435,60,400,75,435,90,450,125,465,90,500,75,465,60"
href="yellow.html" alt="Yellow star.">
</map>
</p>
The math element from the MathML
namespace falls into the embedded content,
phrasing content, and flow content
categories for the purposes of the content models in this
specification.
The semantics of MathML elements are defined by the MathML specification and other applicable specifications. [MATHML]
Here is an example of the use of MathML in an HTML document:
<!DOCTYPE html>
<html>
<head>
<title>The quadratic formula</title>
</head>
<body>
<h1>The quadratic formula</h1>
<p>
<math>
<mi>x</mi>
<mo>=</mo>
<mfrac>
<mrow>
<mo form="prefix">−</mo> <mi>b</mi>
<mo>±</mo>
<msqrt>
<msup> <mi>b</mi> <mn>2</mn> </msup>
<mo>−</mo>
<mn>4</mn> <mo></mo> <mi>a</mi> <mo></mo> <mi>c</mi>
</msqrt>
</mrow>
<mrow>
<mn>2</mn> <mo></mo> <mi>a</mi>
</mrow>
</mfrac>
</math>
</p>
</body>
</html>
The svg element from the SVG
namespace falls into the embedded content,
phrasing content, and flow content
categories for the purposes of the content models in this
specification.
When the SVG foreignObject element contains
elements from the HTML namespace, such elements must
all be flow content. [SVG]
The content model for title elements in the
SVG namespace inside HTML documents is
phrasing content. (This further constrains the
requirements given in the SVG specification.)
The semantics of SVG elements are defined by the SVG specification and other applicable specifications. [SVG]
The SVG specification includes requirements regarding the
handling of elements in the DOM that are not in the SVG namespace,
that are in SVG fragments, and that are not included in a
foreignObject element. This
specification does not define any processing for elements in SVG
fragments that are not in the HTML namespace; they are considered
neither conforming nor non-conforming from the perspective of this
specification.
The width and height attributes on
img, iframe, embed,
object, video, and, when their type attribute is in the Image Button state,
input elements may be specified to give the dimensions
of the visual content of the element (the width and height
respectively, relative to the nominal direction of the output
medium), in CSS pixels. The attributes, if specified, must have
values that are valid
non-negative integers.
The specified dimensions given may differ from the dimensions specified in the resource itself, since the resource may have a resolution that differs from the CSS pixel resolution. (On screens, CSS pixels have a resolution of 96ppi, but in general the CSS pixel resolution depends on the reading distance.) If both attributes are specified, then one of the following statements must be true:
The target ratio is the ratio of the
intrinsic width to the intrinsic height in the resource. The specified width and specified
height are the values of the width and height attributes respectively.
The two attributes must be omitted if the resource in question does not have both an intrinsic width and an intrinsic height.
If the two attributes are both zero, it indicates that the element is not intended for the user (e.g. it might be a part of a service to count page views).
The dimension attributes are not intended to be used to stretch the image.