Hi Edi, see below (although argumentation might be potentially duplicated by Fabio in the other mail)
On 10/31/2009 01:26 PM, Eduard Moraru wrote: > Context left and context right could be an idea. > > However, what do you do about the static size of the context when, for > example, you have a 500 character document and you make only 2 annotations? > That results in storing 2x300 = 600 characters in just 2 annotations. That > is already duplicating the document's content in size. If you make > additional annotations, you duplicate the document several times. > > The part where annotations appear depending on user rights, sounds cool, but > how can you detect when the dynamic content changes and fix your > annotations? (like you do for static content) If I understand correctly what this is about, this is one of the main advantages of storing an annotation with selection and context: the fact that you don't need to update the offsets anytime a document changes, if the selected text is still in the doc, it will be found & shown as annotated. The only issue is about contexts, which, if edited, can prevent identification of an annotation even if annotated text is still there. Static case is simple, diff can be used to do this update. For the dynamic case, various strategies could be applied to detect if the change of context is small enough to consider annotation as still valid (like editing distance, or, equality of one side of the context and not the other, etc). I am trying to imagine how a user perceives an annotation. If one annotated a word in a phrase (or area of content in a page) and then the whole phrase (or content area) changes completely but still happens to contain that word, would the user really expect the word to be displayed as annotated? I would say it's ok not to (which is again one of the advantages of storing an annotation as "what the user sees"). Thanks, Anca > > While I'm not convinced about this approach, you may be right and, comparing > with the existing one (which I did not take the time to understand in detail > as you had), and other issues which you underlined in your reply, it sounds > like a start. > > Thanks, > Eduard > > On Fri, Oct 30, 2009 at 7:25 PM, Anca Luca<[email protected]> wrote: > >> Hi Edi, >> >> On 10/30/2009 06:16 PM, Eduard Moraru wrote: >>> Hi Anca, >>> >>> Here's my understanding of what you suggest: >>> >>> Document text: >>> "word1 word2 word3 word4 word5 word6." >>> >>> Annotation on "word4" results in: >>> - Selection: "word4" (unique within the context) >>> - Context: "word3 word4 word5" (unique within this document) >>> >>> Then all you need to do to mark this annotation, is to locate the >>> document-unique context and then to mark the selection within the >>> document-area defined by the context. >>> >>> I see 2 major issues here: >>> >>> 1. The selection must be itself unique within the context, otherwise you >>> just have the same big problem, at a smaller scale. This directly >>> restricts the context's size. >> >> either use offset for position of selection in context, or use contextLeft >> & >> contextRight (then the whole context becomes contextLeft + selection + >> contextRight) and this doesn't affect context size. >> >>> 2. How can the document-uniqueness of a context be ensured? >>> - Fixed size context is not that practical. >> >> Why? >> It should work well in most real-life cases. My take is that a frame of 3-5 >> hundred characters doesn't repeat in a regular document created in a wiki >> (of >> course you can build test cases when it fails). >> >>> - Computing the context size at creation time with the js client >>> becomes a must, but if it fails to identify such an unique context, you >>> risc having all the document as context. Example document text: "word4 >>> word4 word4 word4 word4 word4" >> >> If the whole document is not megabytes (in which case you should be able to >> find >> a shorter context), I don't see why that is a problem. >> >>> - The matching is done *after* the dynamic part of the document >>> finishes to execute. That dynamic part could potentially generate a copy >>> of the context and confuse the matching algorithm. >> >> Well, the whole point is to get the dynamic part to execute and store >> annotations as text, so that annotations are defined by what the user sees, >> as a >> general idea. This also ensures that an annotation could be displayed even >> if >> its position moved from one execution to another (for example, in a >> scripted >> document, you'd have a part which would only be displayed to admins. If an >> annotation falls in that part, then for admins would match, for regular >> users >> no, which is ok: since the text doesn't appear there's nothing the user >> expects >> to be annotated. If an annotation falls in the part outside the content >> displayed only for admins, then matching by text (and not position) would >> allow >> us to find it and display it even if its position moves because of the text >> rendered only for admins. If it's half-half then for admins it would be >> there >> because the content is, for regular users not because the content isn't). >> For the particular case of a dynamic part generating copies of context, I'm >> reiterating the idea that a couple of hundred characters should work in >> normal >> cases. If there is a dynamic part which duplicates the whole document, the >> only >> problem would be that annotation would be matched and displayed on the >> first >> encounter of its context, and not the second (is that a pb for what user >> sees >> and perceives? or we could also display it 2 times) Also, this is a >> particular >> case ("normal" documents shouldn't do that). >> >> Of course there would be annotations which will fail to be matched and >> represented but, if few enough and in particular enough cases, I think it's >> a >> good tradeoff. >> >> Note that I don't know yet how this performs in practice, but I think it's >> a >> good direction to try as a balance between practical performance and speed >> of >> implementation, and it's the only one so far (well, there's also the >> current >> implementation but that only covers a subset of what this implementation >> would >> cover). >> >> >>> >>> Maybe I misunderstood the proposal or missed some key detail, otherwise, >>> please let me know. >> >> The idea is that this algorithm is changeable in its key points, like >> detecting >> and matching context. This first take is supposed to perform well *in >> practice*, >> even if theoretically there are cases where it fails. If these failures >> make it >> unusable or we decide we want atomic precision, then we can improve the key >> points (like trying to match context better and others). >> >> >> Thanks, >> Anca >> >>> >>> P.S.: I like examples :) >>> >>> Thanks, >>> Eduard >>> >>> On 10/30/2009 05:21 PM, Anca Luca wrote: >>>> Hi devs, >>>> >>>> following a discussion with Fabio about the second desired feature for >> the >>>> annotations, namely the ability to add annotations on any document, no >> matter >>>> how its content is generated, we came up with the solution described at >>>> >> http://dev.xwiki.org/xwiki/bin/view/Design/AnnotationFeature#HSolution1storeannotationsasselectionandcontextovertransformeddocuments >>>> , the main idea being that annotations would be defined by their >> selected text >>>> and a context (as opposed to offsets) and would be identified to be >> rendered in >>>> a document on a serialization of the transformed XDOM of the document, >> this way >>>> taking into account any macro rendering, document inclusion, etc. >>>> >>>> WDYT about this solution? >>>> >>>> Also, because the implementation of this, though relatively localized, >> comes >>>> together with refactor and cleanup of the annotations module (update >> everything >>>> so that annotations don't store and use offsets anymore, remove classes& >>>> functions which are not needed in this simplified process), I propose to >> include >>>> this improvement in version 1.0 of the annotations module (so that we >> don't >>>> cleanup and release what we know for sure we'll delete) and push the 1.0 >> version >>>> further to mid to end December. >>>> >>>> here's my +1 for this, >>>> WDYT? >>>> >>>> >>>> Happy coding, >>>> Anca >>>> >>>> _______________________________________________ >>>> devs mailing list >>>> [email protected] >>>> http://lists.xwiki.org/mailman/listinfo/devs >>>> >>> _______________________________________________ >>> devs mailing list >>> [email protected] >>> http://lists.xwiki.org/mailman/listinfo/devs >> _______________________________________________ >> devs mailing list >> [email protected] >> http://lists.xwiki.org/mailman/listinfo/devs >> > _______________________________________________ > devs mailing list > [email protected] > http://lists.xwiki.org/mailman/listinfo/devs _______________________________________________ devs mailing list [email protected] http://lists.xwiki.org/mailman/listinfo/devs
