On Tue, Mar 11, 2014 at 3:25 PM, Andrei Bucur <abu...@adobe.com> wrote:
> Could you give me an example of that situation? It¹s not very clear to me > what case you are talking about so I can only speculate. To elaborate a > bit what I said in my previous email: > 1. Two fragments overlap during the layout (e.g. negative margins). This > case is handled correctly because layout is the step when fragmentation > actually occurs. Pagination struts and other techniques are applied to > actually construct the fragments internally. > 2. Two fragments overlap at paint time because they¹ve been shifted > somehow from their layout positions (e.g. relative positioning, transforms > etc.). In WebKit, this implies the shifting objects get a so called > self-painting layer. These kind of objects know how to paint themselves as > groups. Using the clipping information computed during the layout, the > layers can contain their fragments correctly. > Suppose I have a font with very long descenders (e.g. Zapfino) and I have content like this: <div style="font-family:Zapfino;">piffle<br>ooof</div> where the descenders of the p and f would normally overlap the second line, but there's a fragment break between the lines. How do you stop the first line's descenders being drawn in the second fragment? Also, we have the so called concept of a region range. This range is > associated with an element and it represents the regions that element is > flowed into. For monolithic elements (images, videos etc.) that range has > a length of one. During paint time, we apply paint rejection outside of > that range so even though a monolithic element is taller than the region > it belongs to, it will not be painted in the following regions. This way > we avoid content slicing. > OK, this sounds like how I think things should work. If this approach works I wonder why you bother with clipping at all. Rob -- Jtehsauts tshaei dS,o n" Wohfy Mdaon yhoaus eanuttehrotraiitny eovni le atrhtohu gthot sf oirng iyvoeu rs ihnesa.r"t sS?o Whhei csha iids teoa stiheer :p atroa lsyazye,d 'mYaonu,r "sGients uapr,e tfaokreg iyvoeunr, 'm aotr atnod sgaoy ,h o'mGee.t" uTph eann dt hwea lmka'n? gBoutt uIp waanndt wyeonut thoo mken.o w _______________________________________________ dev-servo mailing list dev-servo@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-servo
