When I've done similar things, as the whole thing was HTML, rather than generating the bars on the fly, I just had a few bars of each color, and then placed them on the page, giving them a specific width, and an appropriate alt tag (so you'd get a text graph if you looked in lynx ... this was quite some time ago).

Working this way, you just have to iterate through the events, with the following:

printf( '<img src='img/empty.gif' width='%i' height='10' alt='%s'><a h
+ref='%s'><img src='img/%s.gif' width='%i' height='10' alt='%s'></a>',
    $delay_to_next_event / $image_scaling_factor,
    ' ' x ( $delay_to_next_event / $text_scaling_factor ),
    $url_to_event_details,
    $filename_possibly_based_on_event_type,
    $duration_of_event / $image_scaling_factor,
    '*' x ( $duration_of_event / $text_scaling_factor ),
);

[download]

It's rather crude, but it works ... and it worked with what's now 10 year old technology.

Oh -- and generating imagemaps dynamically isn't too hard -- you just generate a client size image map -- loop through the events, and define a rectangle ... of course, you need to get their position relative to the edge, which takes a little bit of extra math, but no more difficult than keeping track of the time between events

In reply to Re: Web Timeline Graphics by jhourcle
in thread Web Timeline Graphics by queeg

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