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HTML clickmaps allow a browser user to click with the mouse on an object or region in a graphic, as if it were a hyperlink to a new web page. Clickmaps work with PNG, GIF, and JPEG images, and require an HTML click map file in addition to the image file. Ploticus (2.02+, all builds) provides clickmap support by generating the clickmap file concurrently with the graphic. Clickmap support is available for pie slice labels , bars , scatterplot points , annotations , legend entries , and the plotting area (divided into subregions as a grid, or in its entirety). A number of examples are provided below. In your web pages, you can use the following HTML construct to add clickmap support for an image:
<a href="mypic.map"> <img src="mypic.png" ismap > </a>
Generating HTML clickmapsClickmap generation is turned on using the -map command line option. This option may be used when generating PNG, GIF, or JPEG images.
It is also necessary to specify clickmap URL information (discussed below) in your script or
prefab
.
(If the script contains clickmap URL attributes but -map isn't used,
no clickmap is generated.)
If two generated clickmap regions overlap, they are stacked in the order generated
(the last generated is on "top").
The clickmap file will have the same name as the graphic result file, except
that a .map suffix will be used.
TroubleshootingIf the -debug command line option is used along with -map, the clickmap regions will be displayed in bright green. If -debug is used in X11 mode, the regions are displayed but no clickmap file is generated.Specifying URLsUsually the programmer supplies URL template(s) or URLs within the script file (eg. for pie graphs this is done within proc pie ; for the plotting area it is done within proc areadef ).For pie graphs, bar graphs, and scatterplots:
For annotations:
For legend entries:
For the plotting area to be a single region:
For grid regions within the plotting area:
To set a default URL for the entire image:
Notes: Embedded spaces and newlines that turn up within URLs will be converted to underscores.
Grid mapping may not be used with more than one plotting area per image.
ExamplesMost of the following examples have been run with -debug to add the green overlay showing where clickable regions are. Try clicking on these images.. they are mapped to a live CGI program that will echo the passed parameters.clickmap_pie
Click on pie slice labels. clickmap_annot
Click on annotations. clickmap_leg
Click on legend entries. clickmap_area2
Mapped plotting area grid. Numeric in X and Y. Click on plotting area. clickmap_area3
Same as above, but with finer granularity. This is done by executing an invisible X axis and an invisible Y axis for the clickmap (in addition to the visible axes) using the automatically determined stub increment, divided by 4. snpmap1
Mapped plotting area grid. Numeric in X; categories in Y. Note that the mapped grid (Y) is influenced by stubslide. colorgrid
Data points are mapped. Click on any data point. clickmap_area
Mapped plotting area grid. Months in X, numeric in Y. Note that month format is controlled using proc axis clickmapvalformat. clickmap_log
Mapped plotting area grid in Y. Log example. Click on plotting area. clickmap_time2
Mapped timeline bars. clickmap_mouse
Mapped plotting area grid. Categories in X. Note that the X stubs are (mostly) included in the mapped regions. This is done using the proc xaxis clickmapextent attribute. clickmap_hit
Mapped plotting area grid. Datetimes in X. The datetimes are mapped in 6 hour increments, even though stubs appear every 24 hours. This is done by executing an invisible X axis for the clickmap, using 6 hour increments. |
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