[daisy] [GSoc] daisydiff progress update 3

[André Ulrich]

Hi Guy,

first thanks for your effort you put into daisy-diff. Seeing what was 
changed is IMHO a key feature within collaborative environments. Your 
visual diff allows the normal user to actually see what is changed from 
his view. What´s next you asked. I would suggest some minor usabilty 
enhancements in order give the user more control and flexibilty to 
navigate through changes. (please see comments below)

Bruno Dumon schrieb:
> On Sat, 2007-08-04 at 07:56 +0200, Marc Portier wrote:
>   
>> We'll have to get some more speculoos in next week to keep you going...
>>
>> fast forward to you questions:
>>
>> Guy Van den Broeck wrote:
>>     
>>> So what's next? Well you tell me. Here are some ideas that spring to
>>> mind:
>>>
>>> - I also noticed that in long texts where very little changed, it is 
>>> hard to find the change.
>>>       
>
> As an example, think of long document where only the href of a link
> changed, it can take quite some time to find where the curly-blue
> underlined link is.
>   
>>  Solutions I see:
>>
>>    1. mark the change with something like a bar in the margin (hoping 
>> this one will not be too small!)
>>     
>>    2. having the bookmark-anchors in place you could maybe provide a 
>> list of all changes in a pop-up window upon clicking some special icon
>>     
>>    3. equally you could think of linking up all balloons with prev-next 
>> links from the one to the other, just needing one bootstrap link to jump 
>> to the first
>>     
>> no idea what would be the easiest, or best from usability POV, anyone else?
>>     
Another solution would be different modes for diffs. When you look at 
TWiki.org for example, they provide different modes to compare revisions:

sequential
 - Demo: http://twiki.org/cgi-bin/rdiff/Codev/TWikiStandAlone?rev1=3;rev2=1
 - displays, also for severeal versions, only the changed part of the 
document.
 - This view is very useful for large documents and many contributors, 
as you don´t have to scoll over the whole document in order to discover 
the change. And you get an overview when something gets changed in a 
timeline order.
 - The view has a parameter called context, which defines the number of 
displayed lines above and below the changed line

side-by-side
 - Demos:
   - 
http://twiki.org/cgi-bin/rdiff/Codev/TWikiStandAlone?rev2=2&rev1=4&render=sidebyside
   - 
http://svn.apache.org/viewvc/apr/apr/trunk/misc/unix/rand.c?r1=382552&r2=384930&pathrev=553146&diff_format=h
 - This is similar to the former suggested columns and will display the 
changes, also for several versions in a timely manner

They also have the option to diplay it in "raw-format". This would 
probably be the old version of diffing, where you can see changes within 
the html code (Bruno would called it CLASSIC)

Anyway, TWiki pages are easy to compare as they use their own markup 
language without tags and so they can utilize the Unix rdiff-tool for 
their diff processing. Do you think it would be possible for your 
algorithm to identify only the changed parts and display them?


>>> -We could add a link to the HTML diff directly on the versions page in
>>> an extra column.
>>>       
>> yes and no...
>> I think we need a direct link for sure, but I don't think we need an 
>> extra column :-)
>>
>> I would rather think that as a user I can set my diff-view preference 
>> and just be brought to that by default.
>>
>> 3 possible values for this preferrence
>> - new view
>> - old view
>> - remember my last usage
>>     

I would like to see some kind of navigation panel for diffs. Right now 
you have to go to "Versions" and choose one combination of versions to 
compare with. When you like to compare a different version you have to 
go back to the list and choose another.

A small navigation panel on top of the diff-view would help to choose 
version combinations without going back to the list of central list of 
versions. Further more it would be possible to directly jump from a 
normal page-view to a diff-view without going through another dialog 
where all the versions are getting displayed.


André