- From: Cameron McCormack <cam@mcc.id.au>
- Date: Sun, 2 Nov 2008 15:39:11 +1100
- To: www-svg@w3.org
Hi Olaf. Dr. Olaf Hoffmann: > 1) > Now it is noted: > "Note that the inverse of the CTM may not always exist. If the CTM is > non-invertible, then rendering of the element is disabled. The 'ref(...)' > value in this case is not an unsupported value." > > If we consider the main idea of the constrained transformation, > as far as I understand this, it is, that the element with such a > transform value ref(...) is not transformed at all and not that > the display is disabled. > I cannot see, that this disabling provides any functionality related > to a constrained transformation or something useful for authors > at all. … > Therefore I suggest to remove the requirement to disable > rendering, if the inverse does not exist, as in the previous > wording, which can be improved maybe, but better not > with constrains on the functionality or with a requirement > to change the behaviour of viewers already managing the > problem without any trouble. I see that there is merit in allowing transform-ref even when its parent has a non-invertible CTM, and after discussing it, I have reverted the text to allow this, but also included a note to point out that the rootmost svg element’s CTM can be looked up directly in this case. > 2) > In '7.6.1 The TransformList value' now appears something > similar contraproductive. It is noted: > > "If the list of transforms includes a matrix with all values set to zero (that > is, 'matrix(0,0,0,0,0,0)'), or any other non-invertible matrix (such > as 'matrix(0,0,0,0,50,50)' or 'scale(1,0)'), then rendering of the element is > disabled. Such a value is not an unsupported value." > > Previously it was noted: > "If the list of transforms includes a matrix with all values set to zero (that > is, matrix(0,0,0,0,0,0)) then rendering of the element is disabled. Such a > value is not an unsupported value." > > > Finally with vector-effect non-scaling-stroke it became a simple > method available to use and to see objects with reduced > dimensionality. To get similar effects and functionalities in > SVG 1.1, this requires clipping, masking, filtering, not available > at all in SVGT1.2. > Therefore it is disappointing that this possibility or functionality > is now removed in a very late phase of the SVGT1.2 drafts without > any reasoning. I guess I’m not convinced that these are useful use cases, but… > My suggestion is, that these possibilities are not excluded, > that authors can use this in combination with vector-effect > non-scaling-stroke to get some tricky functionality (as already > indicated in previous responses about this issue), else not > available in SVGT1.2 at all. …after discussion, I’ve reverted this too. Hopefully this satisfactorily re-resolves your LC comment. Thanks, Cameron -- Cameron McCormack ≝ http://mcc.id.au/
Received on Sunday, 2 November 2008 04:39:50 UTC