Le 03/04/2016 21:58, Igor Stasenko a écrit :
On 3 April 2016 at 22:32, Thierry Goubier <[email protected] <mailto:[email protected]>> wrote: Le 03/04/2016 20:01, Igor Stasenko a écrit : On 3 April 2016 at 20:51, Thierry Goubier <[email protected] <mailto:[email protected]> <mailto:[email protected] <mailto:[email protected]>>> wrote: Le 03/04/2016 19:12, Igor Stasenko a écrit : On 3 April 2016 at 19:48, Thierry Goubier <[email protected] <mailto:[email protected]> <mailto:[email protected] <mailto:[email protected]>> <mailto:[email protected] <mailto:[email protected]> <mailto:[email protected] <mailto:[email protected]>>>> wrote: Le 03/04/2016 17:33, stepharo a écrit : If you want to change clicking behaviour you need to override one single method. Everything you wrote with unreadable amount of characters is for nothing. I see clearly point of Igor. And for me it feels very logical. With such design you can lively change clipping area and interaction area for any morph (element) on screen. In short, i see only two cases where indeed, morph requires a nothing of shapes to define: - clipping region(s) - ui interaction region(s) but for drawing? nooooo... really? who cares what you draw there? draw anything, in any possible way you see fit.. compose, decompose, recombine, blend and mix.. that's the whole purpose of drawing and be artistic and be able to express yourself in any possible way you want :) Why nailing and formalizing things that are tend to be hardly formalizable and more than that, unnecessary. That's my main concern about current design. I agree. I do not see why people are forced to create a submorph just to change the rendering. If you want to change it dynamically you can for example pass a different shape. I don't see the problem with subclassing a morph. Me neither. But do you confusing subclassing and submorph compositing? Let me return you the question then: do you do a composition of submorphs if you're trying to get a different drawOn:? Who, me? No. Maybe i was just misunderstood your reply. Because what i was tried to demonstrate in previous post(s) that there's simply no easy way to expose all possible drawing operations via composition of morphs (or composition of any other kind of elements), unless, of course you will lift full feature set of Athens to the level of composition.. As result you will get a full feature set that Athens provides, plus extra complexity. Sounds like thing to do, no? :) Agreed :) Oh, ok, that's true FastTable does it for the selection... changing background color by encapsulating a row in another Morph with the right background color. Well, i don't know what is FastTable beast are.. so i cannot comment on this one. I think FastTable is something you should have a look at. Esteban did something really interesting there. In FT, Submorphs are only created when they are about to be displayed: Pharo can easily create hundreds of morphs on every redraw cycle. So FT performance is O(k) where k is the number of rows to display on screen (typical k is ~25), and is O(1) regarding the length of the list (almost: there is a point, for very large tree-like structures, where just iterating over the structure becomes the main performance limitation: see FTTree). Sounds like right way to do it. There's no point to keep million UI elements for million items in list, since you never render them all at once on the screen. So, practical approach is to create as many UI elements as fits on the screen, but not as many you have in list. A FTTableContainerMorph recreates all its submorphs on every drawOn:. I've played with different variants (do not recreate all submorphs, for example) but you don't see any performance difference (on the time needed for a drawOn:).
Well, as Henrik pointed out, not everytime ;)
Yeah, i did similar thing in TxText - also create morph(s) only for part of text which is currently displayed.. and basically it is same idea for TxText itself: it calculates layout only for a portion of text, the portion that currently displayed, but never for whole text, which can be megabytes long. Thus, it guarantees that overall performance are bound to the area, covered by UI control that displays the text, but not to text size.
I'm interested to know how you handle scrolling then: how do you define the step, the length and the position: relative to the number of characters displayed / start character of the current UI / and knowing the number of characters in the whole text, so that you are independent of the layout?
Regards, Thierry
