On Sun, Sep 23, 2012, at 01:55 AM, jonat...@mugginsoft.com wrote: > > > > On 22 Sep 2012, at 01:33, Graham Cox <graham....@bigpond.com> wrote: > > > > You might investigate an alternative (and much easier) solution. > > > > NSLayoutManager adopts the NSGlyphStorage protocol. That protocol declares > > a method, -layoutOptions, and one of the flags it can return is > > NSShowInvisibleGlyphs. Simply returning that flag may be all you need to do. > > > > In fact I think this is set for you when you call > > -setShowsInvisibleCharacters:YES > > > > I guess the difference is that it's all or nothing, which might be not the > > desired result. > Works just for space characters, not other whitespace characters. > Plus there is no attribute control so it isn't possible to colourise the > invisible character glyph as I currently do. > > > > > > > > Another approach is to override > > -showCGGlyphs:positions:count:font:matrix:attributes:inContext: which is > > the primitive drawing method. All of the positioning and context > > flippedness has been handled by this point, so you can usually just go > > ahead and draw the characters. Inserting some other glyph at this point for > > the tab should be straightforward. > > > Good idea. > I will investigate this one. > However Kyle's idea of modifying the glyph stream may be better. > It means that there is no second guessing required when it comes to > positioning the substituted glyph. > However, I don't know as yet whether I will be able to specify the > required font colour. We shall see.
Attributes are specified on a character, rather than glyph, basis. So if you need to draw your characters with a separate color, you should probably override -showCGGlyphs:positions:count:font:matrix:attributes:inContext: to push and pop the foreground color you want before calling super. Should be a really simple override, because the context is already set up for you. --Kyle Sluder _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
