WWDC2004 Session 425

Transcript

Kind: captions Language: en afternoon everyone please welcome from apple computer manager of text input and fonts Julia pagalo welcome to section 425 I hope you guys are having an excellent conference this year when we were put in the session together we were wondering what percentage of the developers attending the session would be new to the area carbon test and what percentage would be returning developers so let me start by asking how many are new to this area any anybody all right good how many of you are ready using the sum of the carbon tax day tea is for malkinson excellent we have a session that is packed with information for both you the new developers so that you can quickly orient yourself in this area and for you the developers who have been using our API is relief after release in particular I'm going to start by giving you an overview of the carbon tax ati landscape and i'm going to talk about the api for static text as well as the API for editable text after that I'm going to turn my attention to the H I textview api's and the MLP api's for edit above text and then I'm going to turn the presentation to Tom Madden one of the engineers india sua teen and he'll going to talk to you about Atsui which are the ati you use for laying out that so say that a lot of the applications have a need for static text either for your labels and your controls for your text in your dialogues or some bits and pieces in general of text and for statistics are basically four components and play a key role in this area at the bottom of my diagram is court they opposed to the drawing engine which provides beautiful crisp and clearly of steps on the screen a client of course is at suing apple type services for unicode which is the component responsible for position in the glyphs correctly on your documents and also breaking the lines of text correctly whatever language you use it are using at the time with these Japanese Chinese a Roman language as sweet as the right job the next level up I either the appearance manager in the high-level toolbox or TMNT api's which stands for multilingual text engines in ninety five percent of the cases ninety nine percent of the cases the API that you should use for static text that would recommend you use is the H I theme text API however there are situations in which you need control of the rotated text in which you need control over your the comp the graphic context or you need to use styles other than fonts other than the ones eh I theme fonts provide in that case we recommend you look at the two api's that NLT provides for static text that not enough you need an additional control for your static text then you should look at your 380 eyes and tom is going to talk to you about them the second portion of this presentation the same components they play a role for static text play a role for editable text and you see them on the screen now let's say that you have a male like application that where you have some small text fields on the top of your window say for your recipient or your subject of the email and some large text areas for the content of your email which api's should you use some sort of the small text fields would recommend you use the unique or control and those are being available and the system since the first version of Mac OS 10 for the large text area if you have an application currently running a mac OS and you are using the system APH you're probably using MIT directly which is good however we recommend that for tigers and Beyond utilization to use the HR syntax of straight eh I've textview api's in conjunction with Emily and I'm going to tell you why in a second but before I move on I also want to point out that if you are developing your own text engine in that case you may watch you you want to use your thigh api's directly and again tom is going to talk to you about that in summary if you have static text for most cases take a look at the H ice cream text box ad eyes if you need additional control over styles the graphic context or you need to rotate your text take a look at TX and draw CF string text box API hand those are in the MLT heather and if you need additional control over how your text is rendered please look at the etsu api for edited tech foots text field as i said using Unicode control and that dat iris is on the screen is the ati create unicode air attacks control is the ati you call to create one such text field and for text areas again for tiger and beyond we recommend you start using a chai text view in conjunction with a melty now I'm hearing some of you back in there in the room saying i have an application i'm using the NL ti ti for my text area they work beautifully why should i move on and transition to a chai text you in here at six reasons and they probably did more in the future so if you attended a high-level toolbox sessions during the conference this year you heard that the high-level toolbox team is working hard has been working hard in modernizing the tool the carbon toolbox and then transition into in a hierarchical view model if you use h 8 xu your text areas will be belong to the hierarchy and the advantage of that is that then internally we can take we can use that information to optimize for the instance the rendering of the other objects in addition the order or the carbon events a well-defined if in age if your text area is an H I textview also throughout the conference we been pointed out the importance of supporting accessibility so that your application is available to a wider set of customers if you use H I text you accessibility is built in in your text area there is no what that you need to do in order to make your text area accessible compositing is also supported in a chai text view and in addition is very easy to create an HR 8x you're using the tools their apple provides and I'm going to show you how to do that in a minute last but not least if you have a text nhi tests you the MLT object is still is available to you so that you can extract that object from the h i text you and you can reuse all of that code that you already have in customizing your text area using the MLT api now let me take a quick detour for those of you who are new to the area of carbon Tet and tell you what are the advantages of using Emily what is the MLT provide so emily is a full unicode layout and edited engine and what that does mean to you is that your text area are going to support all of the languages the mac OS and supports you don't need to worry about they are upgrades up through the unicode standard you don't need to worry about learning about how bi-directional text works that is there for you in addition because we leveraged Atsui we had advanced typography i suggest you go and use the typography panel in conjunction with a multi in target to see how you can take advantage of all that which features that we have in the fonts to produce some beautiful text of course we have antialiased s and memory also provides built-in support for multimedia which is important because this edge is very rare the document that contains text only another advantage of a milky ati's is that they provide support for the basic functionality without requiring for you to write any code so for instance you get input text input from any of the input methods in the system whether they are corrected palace keyboard layouts input methods ink it just work selection drag and drop are built in and we also added support for the document axis which are new area which are new carbon events that were introduced in center now that is not enough if you need customization for your text area MLT provides a simple set of 80 is that allows you to customize the text area to your needs and I'm going to show you how to do that in a second but most important I think energy is an evolving and growing side of 80 eyes we've been listening to your feedback and we really thank you for that of what are the areas that are important to you what are the areas where you need new API is to customize your text area and so I like to think of the improvement in MLG into area on the one hand we have the improvement that we do under the hood those are the that's the work that we do at Apple so that your application provides Richard and Richard behavior without you making any changes whatsoever to your code now going to give you an example of that on the other hand we have new api's based on your feedback that allow you to customize your application and deliver to your customers the functionality they need so let's talk a little bit about what we've been working on what are the areas where you can see enhancements in a multi as there are more and more carbon and cocoa application in the system we think it's important that the users get a consistent behavior as they switch from one application to the other so we've been working closely with the cocoa teams to provide a consistent behavior this is working progress but you can notice that there has been some improvements in this area their customers are there are more and more volte lingua so we've been working on improvement or improving the multilingual experience in your text area in particular I want to point out that we have added support for Guinness variants in a tiger so that for instance you can use the typography panel use one of the phones with the has Cliff variants built-in and you can choose the glyphs that you want to represent your name this is it for the instance is important to our Japanese users you can see on this the second line on my screen is three of the spellings for the last name Watanabe and the second character is different in each of the ways they spell it and that is important to Japanese users in addition the capoeira team has been working on improving the conversion accuracy of the input method and the way they did that is by leveraging some new carbon events that allow the input method to get access to the context in your text area we added that support in a multi so that your text areas get better conversion accuracy for Japanese there are people session yesterday we heard that it's important to many of you improvements in Arabic support and I wanted to point out that we've been working on improving our bi-directional text in a multi for instance in pan that we improve how the characters as boundaries between Roman and Arabic we're not there yet we know but we are making progress also if my quest and involves we've been involved in the implementation of MLT you heard at the conference the quick-draw API had been deprecated we had removed that code path in a multi so now that you get absolutely MCG on d in addition we transition our implementation to use QuickTime importers so that now you have a wider set of file formats that you can import into your and multi text area and also we've been working on performance performance performance performance was our mantra using the Panther release and what I show you on the screen is some of the results that if we have between improvements that we have between 10.2 and 10.3 for instance reading in a text document the performance of that operation is 400 times faster scrolling text is 250 times faster and if you select all the text in your document and change the style is 160 times 5 I want to point out that these improvements are not only the result of the air for the MLT team we work closely with the CG and your soy sauce and the rest of of the engineers are apples so this is the result of the combined effort the performance improvement that you have in the current tiger deals are very much comparable to the Panther GM results and we're still working on that so I do expect that by the time uShip Tiger those numbers are going to look even better now that's it old what's new what is the new entire so I very happy to announce that we were able to implement all of your commonly requested ati's in a multi for tiger and so let me start down that list first of all we have a new group and what an undue group is basically it's a sequence of actions that are bracketed be can it be they are bracketed to in a beginning and an end api so that you can give the illusion to your users when they go and click on the undo item that all of those actions Adams undone as a single one and the reason why that is important to some of you is because some they are situations in which you want to initialize your text object with some text change in style add some pictures but then you want your users to undo all of those operations as one take a look at the API they are in the headers there are also some related API that are used for that you can correctly under the undue menu or that MLT handle the undo menu correctly let's talk about scrolling by default MLT you scroll and some of you love it and some of you hate it and the reason why some of you don't like that before behavior is because it's not suited for your application so let's say that you have an application that writes status results to your text window as it runs one of your users is looking at the window and is reviewing the results in the meantime the applications is adding data to the bottom of the text area well MLC is going to score and that might be my via disconcerting behavior so for tigers we added some new tasks that you can control the scroll in behavior the way you like it you can have it as it is by default you can make em out TD head like the terminal in the scrolling behavior or you can tell them until you don't scroll at all until I ask you to do so as I mentioned before if you're using H i text you you get accessibility support for free however if you need to continue your application is to work on back to panted or for whatever other reason and you want to continue to use the MLT a TI we providing you nati to add accessibility support to your text area they say the PX on save and the TXN lady eyes were showing their age they were all they you do some more data structures and on the one hand on the other hand we wanted to add support for that tfd we added support for at PF during the Buzzard release in Java we wanted to extend the support and even more compatible with the coco start another PSP support in addition some of you have been asking for 80 is that allow them to save and retrieve information from memory so for tiger we added to FB i--'s to read and write to CF data and to API to read and write from CF URL in addition there is an auxiliary API that allows you to decide what is the best file format that you need to use in order to save your data without losing and information and and that is important for instance if you want to decide whether it's use at PF or plain text you know another API that we added actually to ati's we added to set and get the event target there's been some confusion in the past where a multi installed a carbon event handlers and so although I haven't seen any feedback on that area recently there was an outstanding requests for api's that allow you to set and get the target event in the targets for the carbon event cinematic and those are there in the multi we also added better ways for you to turn on h high command handling and i'm going to go in some detail on the bardo city is in a minute few more things we added supposed to start checking and we are the support for the Fontan so right now with very few lines of code stop shaking is working in your text area and the very few lines of code that front panel is also working and not only the main front panel but the color subpanel the character palette the typography fun oh and if some of you had tried to do it that's quite a fair amount of wood so we have simplified that in condition all right so two words of caution one is as Steve mentioned we are showing you tiger is soon a lot earlier than other releases so the api's are they are the basic implementation is there we're still working on that so the second word that I want to say is please give them a try we've been implementing them response to your request we love to hear what you have to say and whether there are things that we need to tweak all right so what I want now to do is a more hands-on approach I'm going to show you how to build a nature textview to show you the event managers can do it and how to actually customize it and then I'm going to move on and give you some tips and tricks on about optimization so again can I have the demo machine please the other dimensions thank you so I have interfaced yielded running all right thank you so I'm going to create a carbon app with the menu may with the menu bar and just for the purpose of this demonstration so that you can see the contrast between the background and the text area I'm going to make it metal and now i'm going to drag and drop from the carbon palace the text area i'm going to resize it just resize it and i'm going to do one more thing i'm going to give you an egg give the text view its signature and an ID so that later on i can retrieve it in my application and when i give it the signature text and the ID 0 and right well so i have nhi to you with an emoji object inside it and i can type maybe i can switch to japanese and I can touch Japanese have right with me no line of code I can bring up word texts and I can copy and paste next text so all of that but just dragging and dropping in a few clicks so what can I have stage lights stick so that shows you how to build your H I Texas but and maybe the basic functionality is all you need but say that you need to add some margins you wanted to retrieve the text you want to add some tests programmatically then in that case if you need to customize your H i text you you want to use the NLT a tree eyes and if you have been doing so that you can transition your creation of the text area to do search i text you and then take advantage of all the other code that you already have so this is my detour for the folks there and need to be Syria so let me give give you some basics about Emma to use very simple MLP represents your text area your document within a txn object which is an opaque object if users object white controls each area called object controls and EMS you uses the concept of style attributes that are by run so for instance you can have your text is divided in chunks of for offset 0 to have to plan your texts lucida point size 10 blue from after 11 to offset 15 is half load test point size 18 green and so on and so forth now another key concept to a multi is carbon event and I wanted to say four things about that so the first one is if you're using nhi textview MLT is going to install the carbon event handlers on your own in view and it's going to install all of them and creation time some of them are be going to be turned on some are now going to be are going to be off but the important point here is that all installed at the same time so that reason why that is important so you have a good picture of where in the stack of your carbon events a monkey has input is on event handlers by default we turn on the input the text input event so that you can type in using any of the input methods and the document access events which are used by the input methods as well in addition you can turn on support for DHI commands weather is for your edit menu for spell check in on the fun or for the phone panel but those are off by default and you can turn it on for later so that ends my detour now remember we had our GHI text view and I'm going to show you how to extract the MLT object so here it is first of all we have a constant that allow us to identify that particular view in our hierarchy after that I going to call some standard high-level toolbox ati's to find the hood of the hierarchy and extract a particular view that I'm interested in this case ehh i text you and once I have the H I text you I can call hhx you get TX an object and that gives me the emoji object now I'm good to go alright so to show you how to use the MIT api's I'm going to demonstrate how you can turn on spell checking and it's going to be very simple NM LT leverages the H high command support that we added for tigers to turn on spell check so let me remind you what I be a trike man so we have two flavors of HR commensurate recommend process events which are the advance that sent when your users click on a menu item or set select menu item of clicks under control and then the rabbit I try update status events which are the events are dispatched to your application when in UI elements needs updating for instance before your menu comes up you get one of those events which you have a chance to update the information in the look of the items in your menu we recommend that you handle all of the H I commands for the menu or none of them to avoid compatibility issues in the future and that's actually the way we did it for a multi so for Tiger winter we are introducing the TX and said command event support which allows you to turn on and off support for basically three groups of H I common for editing for stout shaking and for the fun part and those those three flavors both for processing and updates testers I'm not going to go through the details of that you see on the table but surface is to say that you have three options that you can turn on and those enable the handling of the H high command's in a multi so for instance if you decided you wanna melt you to handle they edit command processing events and multi will do so annual handle the undo redo select all and so on all right now how do we turn start checking on very simple we set the options for the HR I commands that we want the spell checking in this case and then we call TX and set command event support with the MLT option and the options that we set and that's it from that point on spell checking is going to work now what is it going to what is that you're going to see in your application when you turn start checking on so if you have new spells they are going to show up as red dotted underline in addition we provide a contextual support for the contextual menu and we added some api's so that you can modify the content of that contextual menu if you choose to so MIT is going to handle the contextual menu but we're going to give you a choice modified as you need and also we provide support for the spelling panel so if this dead the hy commands for the spelling finally sent a multi would react to that and show to spend in panel so that your user can select it dictionary learn a new word spelling and so on if that looks familiar to you that is because we implement the same UI is Coco so we were talking about that consistency between carbon in cocoa and we wanted to put you know in breach that so they day you I is exactly the same you use the same spell check in ng and the same set of dictionaries alright so as with that I show you how to create your H i text you you how to extract the emoji object how to customize it now as important is that to use the API is important also that you use them correctly and I'm going to give you some tips that will learn over the recent months by working with developers and analyzing the performance of their application so the first one is their cases in which is you don't need all of the rich style texted MLG supports what you really need is one of style text in that case would recommend you use ktx and mono style text mask when you create your object that allows us to optimize the brake line operations because they hyped the height of the text is constant for tiger we introduced the KTX and disable layout and pro tab which is useful when you do multiple sequential modifications to your msg object so basically what you want to do is you want to set the mask on modify your objects turn it off and draw and that way MIT will not draw and brake lines in between operations that is the same behavior as the KTX and disability tag used to give you but the name was really confusing so we decided to introduce its as it has a name for what it really does if your text and with carriage returns then you want to use the KTX and word wraps data and set it to nor wrap that way we can avoid doing unnecessary line breaks which could be an expensive operation in the case of Unicode and text as important that they do teach at the things that you should not do the model in a multi nh-8 xu is that a muskie are we asked to changes to the object by redrawing so in most cases you don't need you do not need to call the x and draw one exception is if you use the TX and disable a disabled layout and draw up after you will be enabled laying out and drawing the test you want to call TX and draw and that is because I was implemented long time ago that way and we didn't want to change it to avoid performance impact also unless you really do need it do not use the KTX and always rapid view edge mask what that mask does is keeps your destination rectangle of your texts pin to the direct of your window so as you resize your window your text we're crazily breaking lines and rejoin your text and that sometimes it's not the behavior you want so keep an eye on that if you need it feel free to user we improve the performance of that operation quite a bit but if you didn't need it done said all right and with that i'm going to give you a quick demo of then you api's working on tiger let me clean up some okay so what I have here is a multi showcase that's an application that we put together one of the engineers in the teen road for WWDC you have it in your SDK feel free to play with it and give us feedback so what you see is the large text area is a nature a text view in Anna multi-object the small text area on top of that is a unicode control and we put some radio buttons to control the behavior because one of the feedback that we heard is that did you want to be able to manage the behavior of your text objects for any from any kinds of controls not only for menus so the first thing I'm going to do is I'm going to turn on spell check in and I am going to start typing and I have practice next so while they cannot make a typing mistake there you are so as I tried the red dotted underline comes up and all of the lines of code that our Dean executed is the one that I show you we don't have contextual menus you're working yet in this application but you will be there soon and there should okay let me move on to the front panel and I'm going to select this paragraph I'm going to change the font choose huh flirt text I'm going to hello yeah thank you they're all right so as you see I have all of the different options for changing the style in the from the front panel working with a multi object I can even bring up the color palette and change the color I can strike through I can underlie so all of the different palettes just work and again this is by turning off the H high command vent support in a multi we have let them hear a way to show you how the undo groups work by an on going to have time to go into that and so let me just show you the no scrolling in action so let me copy copy alright nevermind as I said this is working progress let me copy the text and let me put my insertion point at the bottom and i'm going to paste it and as you see as I paste the text MLT is going to scroll so now we're going to turn no scrolling and i'm going to start pasting nothing happens as you see this the scroll body is getting smaller because the size of my text objects is increasing and actually the text has been pasted at the bottom of the of the object but there is no scrolling action then the next to write your buttons is going to show you how to use reading and writing to a CF URL and you can take a look at that and again give us feedback and with that I'm going to end up stay in Matthew session and I'm going to turn the presentation to Tom marriage take you how's everybody doing good conference so my name is Tom medan I'm a engineer and I've been working on em Suey for a little while now well let's get started absolutely is an acronym that stands for apple type services for Unicode imaging today I'm going to cover kind of what it is and why you should use it I'm going to cover some basic Atsui construct some things you would need to know to get started using up suey I'm gonna cover how to do some line breaking drawing then I'm going to cover some advanced features and I'm going to give you some performance tips for those of you who are considering using s3 or have already adopted it so without further ado what is that suey well that's two is the low level unicode layout engine at tsui is used by all those things that Julia just showed to actually take the Unicode text that's used as an input and display it on the screen absolutely provides layout services for all those things plus it provides some services for app get it provides services for safari and a whole bunch of other apps so you might be asking yourself what is layout we've been using the word lay out the whole presentation some of you may or may not know what it is well layout is simply the process of taking the Unicode text and converting it to glyphs and physicians which gets then fed into the courts rendering engine the glyphs are and positions are determined by two things first of all the layout tables that are embedded in the font Atsui supports opentype font layout tables which are the G pause in the G sub table as well as the AAT font layout tables it's always supported those in addition to the layout tables it also requires character properties unicode has a great character properties database where it can find all sorts of information about the characters so it takes those two bits of data munches them together and out come the glyphs and the positions so besides the standard character to glyph mapping reordering and stuff like that that's required by layout absolutely also does a couple other things the first is automatic font substitution automatic font substitution allows that fooi to substitute a new font should the fonts that you have selected not be able to map the characters that the user has input into Atsui so for instance let's say you have selected times new roman and then the user has input a japanese text times new roman can't display japanese so x we will go out and substitute a new font for it most likely hiiragi know additionally absolutely provides API for style management there's an there's an absolute style object which I'll get to in to in a minute it provides API for line breaking which can be pretty tricky in the case of Unicode and it also provides API to help you if you had an editable document so you've seen all the stuff that julia has you've seen the MLT ml te you've seen the h i text view you might be asking yourself why should use that tsui directly well if you need the ultimate control over the text you would use that tsui with that suit you can control the line breaks you can control the position the exact position of the text you can even go into the glyphs and change their positions directly in addition at suite provides broader options for tracking justification kerning flush pneus and all this other stuff that you may want to control directly in addition if you have custom rendering paths such as you want to go out to you know say in OpenGL context or something like that you may want to use that tsui as well what absolutely will also get you switching to etsy we directly is speed in a sense those AP is that that Julia mentioned and a lot of the other ati's in the system their whole purpose is to feed Atsui unicode techs and to manage their silly objects for you but if you can do a better job at doing that then you will get a better a you will get faster operations because these objects in some cases were designed for more general case so you've decided okay I need to use that suey so what do you need to know to get started well the first is you need to know about unicode the unicode text buffer that you provide to ETSU II must be in the utf-16 format Atsui doesn't accept utf-8 doesn't accept utf-32 only accepts utf-16 you can get your text into utf-16 format using CF string or text encoding converter whatever it just has to be in u.s. utf-16 format the second thing that's very important is that you own the text buffer you can't free the text buffer out for Matsui if you do that bad things will happen Atsui does not retain the text buffer and so he doesn't do anything like that you manage it you own it and likewise if you should change any of the text in that text buffer you have to notify Atsui so if you insert text delete text move the buffer around you have to call an API which I'll show you in a minute finally one important note that has tripped up more than one person is that the character the glyph mapping is not necessarily one-to-one even in the case of simple ASCII English Roman text so one of the most blatant examples is the FI ligature you have a F character and an AI character which combine to form a single glyph and so if your code makes assumptions that the there will be one character for one glyph it will break in a lot of cases so you have your unicode text buffer it's in utf-16 it's ready to go you want to do something with it so what do you do with it the first thing you have to do is tell that silly where it is and you do that by creating an absolute text layout the absolute text layout is simply an object that references your unicode text buffer to inside that s to text layout you also it also tracks the style assignments so you take a range of that buffer and you sign it to Helvetica you assigned it time you sign it to two different fonts or different styles it also tracks the line breaks it tracks the font fallbacks which are which allow you to customize that font substitution behavior that I talked about earlier and it also tracks the tab rulers and the tab stops you modify the fat suit text layout by setting layout and line controls on it and there's a there's a couple api's that allow you to do that and finally and perhaps most importantly the absolute text layout will store the cache lines glyphs and so if you're constantly creating these things and throwing them out you're going to get rid of a lot of work and your application will run slower because that whole layout process that I had that graphic up there for that can be an expensive process because it has to read in font tables and interpret the characters if you throw that work out and have to recreate it your your application is doing a lot of extra work so to create an absolute text loud it's pretty simple we have an API called as to create text layout you just call out to create text layout and you have a layout it's empty doesn't do anything yet so you have to assign some text to it we have an API called absolute set text pointer location you call that to set you to assign the buffer to it and then finally we always recommend that you call absolute set transient font matching this will turn on the font substitution behavior as I described before it's off by default if you don't turn this on what will happen is if you should encounter some text that you're currently selected font can't render you'll get ugly little boxes and that's not pretty so you have your absolute text layout it's it's kind of boring it doesn't really do anything yet in fact if you try and pass it to a draw API or measurement API you'll get an error because it doesn't know what to do yet so to make it much more useful you have to assign a font to it you have to sign some style to it and so you do that what the apps style object which is simply a collection of the stylistic attributes it's the font the color the point size all this stuff that you want to kind of style as the text with you take that fu style and you assign it to a range of text within that a suit text layout now an important point is that once it's assigned to an absolute text layout you can go ahead and assign it to as many other etsu text layouts if you want it's not tied to any specific text layout you can you can reuse it over and over again in fact that's recommended because you'll be creating fewer objects so to create an absolute textile the first thing you do is you call as who create style and that creates a blank style it's set up with all the defaults in fact you can use it right away it's just maybe not what you want i think it's set up with Helvetica 12 point and a couple other defaults so to get it more to get it into a shape that you would want to be able to use it in you have to set some attributes to it here i'm setting the font tag which will set a font a specific font to that style and a size tag which will set a specific size to that style once i have the tag set up i call lets you set attributes with the tags and the values and that will set everything up and it'll be ready to go so once you have your absolute style set up you assign it to the text layout to arrange them the text layout using a sous cette run style so your text layout is all ready to go you have the style set you have all the text in it but there's one problem it's all one line and so for some folks that may be okay but if you have a haven't have an application that requires line wrapping a line breaking you need to call Atsui to do the line breaking for you Atsui has 29 brittany api's one is called ETSU batch brake lines and that's an API that is optimized for breaking constant with lines and so for instance if we're breaking inside a rectangle or if you are breaking down a constant with barrier you can use that suit batch brake lines absolute brake line is used in the situation as could be used for the situation pictured above where you would want to vary the line with in this case we're trying to wrap around an object so the line with on this side are a little shorter than the line with below so that's your batch brake lines sets multiple brake lines at once and it requires that you have a constant width and so here breaking into a box as to batch brake lines is is used simple the first thing we recommend is that you set the width in the object you can specify a width to the batch brake lines API but the problem is that with is only used for line breaking so if you go and apply a flush nest or a centering or some other you know AP item to that requires a with that width won't apply and so you need you would need to go and set the width anyway so we recommend you just do it before so you do as you set layout controls with that with and then you simply call a soubrette batch brake lines and it will go down and set all the line breaks to that with you've specified if you need to do non-constant with breaking if you need to vary align with if we need to do other things like that we have the absolute brake line API and that will let you set the width for every operation an important thing here is to let Atsui set the line break once it's found it at su brake line can be used in a mode where it can just find the brake for you which may be what you want but it's recommended that you let em sua set the brake once it's found it and you do that by passing in a parameter which I'll show you in a minute this is important because if you don't let us do we set the brake it will have to go back and refigure out that break when you go and set it so you'll throw out a little bit work so this code up here does the same exact code as the batch brake lines example that I showed you it just uses the brake line API so like before the first thing you do is you set the line with in this case we're using a constant with the next thing you'll probably want to do is get the character count so you know where to stop breaking the lines you set the brake to start at the beginning then you call a su brake line in the loop until it's consumed all the characters so the next thing you probably want to do is now that you have your you're nice as you text layout you have all the lines broken you have all the styles of sign is that you probably want to draw it absolutely has a function called absolute draw text and the important point here is it draws one line at a time so you'll have to draw those lines individually you should always specify a CG context and you do that via a text or a line layout option or a line or a text layout option in the absolute text layout you do absolute set layout attributes with the CG context and then it'll be set in the text layout let's say the reason why you do that because if you don't set a text layout Atsui has a quick-draw fallback mode and so if you don't set a CG context it'll have to go through and look up a CG context for you from the current quick-draw port which is a very expensive operation so if you set that fiji context beforehand you'll avoid all that work another important thing to remember when you draw text is that you need to flush the CG context if you don't flush the CG context you probably won't see anything but you should only flush at once and so if you're drawing a whole paragraph worth of text you want to flush it after you've drawn all the lines so some of you have have needs you're writing a text editor you're writing a an application that has editable text you'll need you'll need to use some editing api's Atsui has hit testing and cursor handling api's i'm not going to go through those we have highlighting api's to handle the highlighting and unhide aligning text and these are kind of useful because in unicode techs the highlighted areas can be discontinuous depending on the directionality in such of the text in addition we have three api's that will be required it should you ever insert or delete or move text and there are listed up there on the screen some advanced features that a absolutely has that you may be interested in is we have the absolute glyph selector to specify a glyph variant you specify this absolu glyph selector in the style and that allows you to do the glyph variant support that Julia showed you that ml te handles for you as so we also has the absolute direct access calls and these allow you to get exact glyphs and glyph physicians and all sorts of other information out of the layout for those of you who want to do your own positional manipulations or supply your own metrics as so we also have some flattening api's for pasteboard experts exports this will allow you to take the app to styles that you've set in the in the layout flatten them all to a binary format so you can put them all up on the pace board or save them to disk and finally absolutely have some curve access api's and these are really cool because they allow you to get at the curves that if tsui is giving to the graphics engine to draw the glyphs so some applications such as motion have used these to actually do animated text and other cool effects with those curves so some some folks have a half first and performance tips besides some of the ones that have been given throughout the presentation you should use the absolute get bliss bounds API for measuring the text whenever possible absolutely provides several API is for measurement and this is the only one that's guaranteed not to accept upset any of the cache data some of the API is require it to do some extra processing work to get the correct measurement the measurement that you requested for this will give you a typographic bound that's guaranteed to not upset the cache layout second thing if you are getting the curves you should call ETSU get native curve type before accessing the curve and set up your curve callbacks according to the result of that some fonts have curves accepts and cute or some fonts have curves stored in cubix some fonts have curves store in quadratics and if you use the wrong type Atsui has to convert the cubes to quads and the quads two cubed and that's that's not an expensive process and may give you some ugly-looking text if you go to draw those those curves finally if there's anything that you should take away from in terms of that silly performance is that you should maximize the object lifetimes meaning that you should not throw away these objects until you're absolutely done with them keep the text layout objects around keep the appt su style objects around following that you want to minimize the object creation you want to create as few eps of styles as possible and you want to create a few apps and text layouts as your application requires so that wraps up the Atsui section of the of the session and there's a couple things that you should take away first is that you should use the hii theme text API for static text it makes things a lot easier you can create these things in project builder second use the unicode control api for text fields and these are the small little text boxes such as password fields and in little search fields and stuff like that third use the H I text view oh and the M LTE API for text to protect areas these are large you know document sized or large input areas fourth you can use that tsui for maximum or ultimate control on the text layout and drawing fifth use the use the API optimally for the best performance that includes keeping objects around not throwing them out creating a few objects as possible turning off visibility on your M LTE objects when you're doing lots of hits and stuff like that and finally you need to file bug reports should you see anything wrong we're doing our best to test these things but every now and then well I shouldn't say every now and then but everything we get we get very good bug reports from you guys from the field and we do fix those and we do see those problems so with that I'd like to bring up xavi a for the wrap-up and the QA thank you you