2014-07-06 9:54 GMT+02:00 stepharo <steph...@free.fr>: > Hi peter > > I hope that igor will see your mail now I will try to reply and this may > be a bit wrong :) > > > Hello, >> >> I'm currently working on drawing engine (à la Squeak Connectors) as a >> part of school project and have a couple of questions about Morphs and >> Athens and would be grateful if someone could enlighten me. >> >> What is the difference between "Morph>>#drawOn:" and >> "Morph>>#drawOnAthensCanvas:" if I draw on AthensCairoSurface? Should I >> always use the latter or will there be switch to the former once everything >> is rendered using Athens? >> > AthensWrapMorph fullDrawOn method will call its submorphs drawOn: method with an AthensCanvas. Now, if you have an AthensCanvas (from the AthensWrapMorph) and your own Morph does not implement drawOnAthensCanvas, then Morph>>#drawOnAthensCanvas is called which just draws an rectangle from your Morphs bound. For example, put a PolygonMorph on an AthensWrapMorph. It is drawn as a rectangle, because PolygonMorph does not know (yet) how to draw itself with athens.
If you have new a Morph that is just container of other Morphs than you don't need to change anything. Just make sure your toplevel Morph is wrapped by an AthensWrapMorph. But If you have a Morph, that subclasses another Morph that overrides drawOnAthensCanvas, you'll have to reimplent this as well. For example, MenuItemMorph subclasses StringMorph and StringMorph implements its own drawOnAthensCanvas. If you put a MenuMorph in a AthensWrapMorph it will be drawn like a plain StringMorph not like a MenuItemMorph (without icons and arrows for submenus etc). > One of the idea is that you have a wrappingMorph that convert the Morphic > to Athens drawing. This way > you can use athens and still be in a non athens world, then we will switch > to athens you will just have to unwrap your (athensihed morph). > Now about the granularity question it depends, what I would do is to have > one wrapper and be in a athens world. > Did you check the trachel layer in Roassal? > I may be wrong, but I think we have to be carefull that not everyone invents its own "draw on athens layer". I would suggest: - build it on top of roassal / trachel, i.e. draw always with athens. - build it as Morphs and implement drawOnAthensCanvs if needed. Nicolai > > What would be good is that > - you define drawOnAthensCanvas: for all the shapes you need and we > integrate them into Pharo > - like that slowly we will get ready to switch to Athens > > > Should AthensMorphWrap be around every morphic element or just the top >> level? i.e. >> CanvasMorph (owner of the surface) will have a single submorph >> AthensMorphWrap which will then hold all the morphs (EllipsisMorph, >> RectangleMorph, ...) which are being drawn on the canvas. >> > I think so. > This is what Roassal is doing. > Please keep us aware of your progress and do not hesitate to ask questions > and we are REALLY interested in your project So if you have athens draw on method please send them to us. > > Stef > > >> Thanks, >> Peter >> > > >
