[Pharo-project] TxTextMorph based on new text model
Sean wrote: Denis Kudriashov wrote Do you think that presenting any letter with real object (not just character) is sufficient for modern computers? I think not. Of course such model significantly simplified all logic around text layout stuff. But I think it is too expensive. In a case study on designing a document editor in 'Design Patterns (1995)' , there is a reference to a thesis from 1993 showing that using Flyweight or sharing commonality makes it fast enough. I assume that was c++, but 20 years of hardware improvements should be enough. Paul R Calder. Building User Interfaces with Lightweight Objects. PhD Thesis, Stanford University, 1993 I don't know how efficient it would be, but how much text do we really layout at once? If it makes the code simpler and more beautiful, then it would be my starting point. Doing otherwise is premature optimization. One book at a time. In multiple columns, with tables. But we don't need to show more than one screenful at a time. I noticed the current strategy seems to be to make a very simple model work, and add abstractions late. That means a lot of refactorings will be needed. Cocoa fundamental abstractions are TextStorage, LayoutManager, TextContainer and TextView. LayoutManager uses TypeSetter(s) to layout glyphs in lines according to the dimensions of one or more text container objects in one or more text views, directs the GlyphGenerator to translate characters in the textstorage into glyphs... Stephan
Re: [Pharo-project] TxTextMorph based on new text model
I guess if we could have something that lays out basic text properly (e.g. bold/italics do not mess everything) and a ParagraphcomposeAll: that works, it would be a huge plus. The main issue IMV is that we keep on recreating Paragraphs and that whole logic should be revised. Phil 2013/2/15 Stephan Eggermont step...@stack.nl: Sean wrote: Denis Kudriashov wrote Do you think that presenting any letter with real object (not just character) is sufficient for modern computers? I think not. Of course such model significantly simplified all logic around text layout stuff. But I think it is too expensive. In a case study on designing a document editor in 'Design Patterns (1995)' , there is a reference to a thesis from 1993 showing that using Flyweight or sharing commonality makes it fast enough. I assume that was c++, but 20 years of hardware improvements should be enough. Paul R Calder. Building User Interfaces with Lightweight Objects. PhD Thesis, Stanford University, 1993 I don't know how efficient it would be, but how much text do we really layout at once? If it makes the code simpler and more beautiful, then it would be my starting point. Doing otherwise is premature optimization. One book at a time. In multiple columns, with tables. But we don't need to show more than one screenful at a time. I noticed the current strategy seems to be to make a very simple model work, and add abstractions late. That means a lot of refactorings will be needed. Cocoa fundamental abstractions are TextStorage, LayoutManager, TextContainer and TextView. LayoutManager uses TypeSetter(s) to layout glyphs in lines according to the dimensions of one or more text container objects in one or more text views, directs the GlyphGenerator to translate characters in the textstorage into glyphs... Stephan
Re: [Pharo-project] TxTextMorph based on new text model
Thanks again for tackling this! I'm definitely available to collaborate :) Denis Kudriashov wrote Do you think that presenting any letter with real object (not just character) is sufficient for modern computers? I think not. Of course such model significantly simplified all logic around text layout stuff. But I think it is too expensive. I don't know how efficient it would be, but how much text do we really layout at once? If it makes the code simpler and more beautiful, then it would be my starting point. Doing otherwise is premature optimization. Denis Kudriashov wrote Another thing which I always not agree is introduction scripting languages inside smalltalk... [but] I like what they do inside rules. It is really simple and understandable code. Yes, I think a special scripting language would be way outside the bounds of Pharo, but the rules idea simplicity of that style could be great for us :) Cheers, Sean -- View this message in context: http://forum.world.st/TxTextMorph-based-on-new-text-model-tp4663219p4669991.html Sent from the Pharo Smalltalk mailing list archive at Nabble.com.
Re: [Pharo-project] TxTextMorph based on new text model
Hi, this is really interesting! To have a simpler text model and UI. I recall Safara, in squeaksource. Lukas and a student worked on a nice text model. Worth checking it out. Fernando On Fri, Feb 15, 2013 at 12:29 AM, Sean P. DeNigris s...@clipperadams.comwrote: Thanks again for tackling this! I'm definitely available to collaborate :) Denis Kudriashov wrote Do you think that presenting any letter with real object (not just character) is sufficient for modern computers? I think not. Of course such model significantly simplified all logic around text layout stuff. But I think it is too expensive. I don't know how efficient it would be, but how much text do we really layout at once? If it makes the code simpler and more beautiful, then it would be my starting point. Doing otherwise is premature optimization. Denis Kudriashov wrote Another thing which I always not agree is introduction scripting languages inside smalltalk... [but] I like what they do inside rules. It is really simple and understandable code. Yes, I think a special scripting language would be way outside the bounds of Pharo, but the rules idea simplicity of that style could be great for us :) Cheers, Sean -- View this message in context: http://forum.world.st/TxTextMorph-based-on-new-text-model-tp4663219p4669991.html Sent from the Pharo Smalltalk mailing list archive at Nabble.com.
Re: [Pharo-project] TxTextMorph based on new text model
On 28 January 2013 19:37, Stéphane Ducasse stephane.duca...@inria.fr wrote: This was experimental. Do not lose your time with it. Now you know that you should continue :) This was to prove that kids could define even texteditor with simple rules. that 'script' called DSL :) so, yes.. you can write text editor with 10 lines of DSL code.. + 100+ lines of code for DSL parser + numerous hours for developers to master your DSL before they can understand/change the code :) Stef Here is the paper: http://www.vpri.org/pdf/m2010002_lobjects.pdf And you can download the image with the actual active essay from http://tinlizzie.org/lesserphic2/Text%20Field%20for%20LObject.zip I read paper and play with image. And I have not good impression about this work. First they present text with real objects for each letter. Each letter is actually big object with x, y, predecessor, successor and other attributes. How much memory such model required? Do you think that presenting any letter with real object (not just character) is sufficient for modern computers? I think not. Of course such model significantly simplified all logic around text layout stuff. But I think it is too expensive. Another thing which I always not agree is introduction scripting languages inside smalltalk. In paper all layout logic (and editing too) programmed by system of rules in special scripting language (very similar to smalltalk). If you look deeply you will see that rules call other rules with same way methods call other methods in basic smalltalk code. So I don't see any value of rules idea expressed with special scripts. In spite of my non positive opinion I like what they do inside rules. It is really simple and understandable code. Maybe I will try reuse something. Best regards, Denis -- Best regards, Igor Stasenko.
Re: [Pharo-project] TxTextMorph based on new text model
Hi 2013/1/29 Igor Stasenko siguc...@gmail.com On 28 January 2013 19:37, Stéphane Ducasse stephane.duca...@inria.fr wrote: This was experimental. Do not lose your time with it. Now you know that you should continue :) This was to prove that kids could define even texteditor with simple rules. that 'script' called DSL :) so, yes.. you can write text editor with 10 lines of DSL code.. + 100+ lines of code for DSL parser + numerous hours for developers to master your DSL before they can understand/change the code :) I think you all agree that smalltalk is powerfull enough to be DSL for any domain/problem. No needs for special syntax Stef Here is the paper: http://www.vpri.org/pdf/m2010002_lobjects.pdf And you can download the image with the actual active essay from http://tinlizzie.org/lesserphic2/Text%20Field%20for%20LObject.zip I read paper and play with image. And I have not good impression about this work. First they present text with real objects for each letter. Each letter is actually big object with x, y, predecessor, successor and other attributes. How much memory such model required? Do you think that presenting any letter with real object (not just character) is sufficient for modern computers? I think not. Of course such model significantly simplified all logic around text layout stuff. But I think it is too expensive. Another thing which I always not agree is introduction scripting languages inside smalltalk. In paper all layout logic (and editing too) programmed by system of rules in special scripting language (very similar to smalltalk). If you look deeply you will see that rules call other rules with same way methods call other methods in basic smalltalk code. So I don't see any value of rules idea expressed with special scripts. In spite of my non positive opinion I like what they do inside rules. It is really simple and understandable code. Maybe I will try reuse something. Best regards, Denis -- Best regards, Igor Stasenko.
Re: [Pharo-project] TxTextMorph based on new text model
Hello 2013/1/24 DeNigris Sean s...@clipperadams.com I don't. Do you have link? Here is the paper: http://www.vpri.org/pdf/m2010002_lobjects.pdf And you can download the image with the actual active essay from http://tinlizzie.org/lesserphic2/Text%20Field%20for%20LObject.zip I read paper and play with image. And I have not good impression about this work. First they present text with real objects for each letter. Each letter is actually big object with x, y, predecessor, successor and other attributes. How much memory such model required? Do you think that presenting any letter with real object (not just character) is sufficient for modern computers? I think not. Of course such model significantly simplified all logic around text layout stuff. But I think it is too expensive. Another thing which I always not agree is introduction scripting languages inside smalltalk. In paper all layout logic (and editing too) programmed by system of rules in special scripting language (very similar to smalltalk). If you look deeply you will see that rules call other rules with same way methods call other methods in basic smalltalk code. So I don't see any value of rules idea expressed with special scripts. In spite of my non positive opinion I like what they do inside rules. It is really simple and understandable code. Maybe I will try reuse something. Best regards, Denis
Re: [Pharo-project] TxTextMorph based on new text model
This was experimental. Do not lose your time with it. Now you know that you should continue :) This was to prove that kids could define even texteditor with simple rules. Stef Here is the paper: http://www.vpri.org/pdf/m2010002_lobjects.pdf And you can download the image with the actual active essay from http://tinlizzie.org/lesserphic2/Text%20Field%20for%20LObject.zip I read paper and play with image. And I have not good impression about this work. First they present text with real objects for each letter. Each letter is actually big object with x, y, predecessor, successor and other attributes. How much memory such model required? Do you think that presenting any letter with real object (not just character) is sufficient for modern computers? I think not. Of course such model significantly simplified all logic around text layout stuff. But I think it is too expensive. Another thing which I always not agree is introduction scripting languages inside smalltalk. In paper all layout logic (and editing too) programmed by system of rules in special scripting language (very similar to smalltalk). If you look deeply you will see that rules call other rules with same way methods call other methods in basic smalltalk code. So I don't see any value of rules idea expressed with special scripts. In spite of my non positive opinion I like what they do inside rules. It is really simple and understandable code. Maybe I will try reuse something. Best regards, Denis
Re: [Pharo-project] TxTextMorph based on new text model
Denis Kudriashov wrote I like what they do inside rules. It is really simple and understandable code. Maybe I will try reuse something. Very good. I am not suggesting we copy the exact approach, just learn any lessons so we don't have to repeat the mistakes of the past. Sean -- View this message in context: http://forum.world.st/TxTextMorph-based-on-new-text-model-tp4663219p4665942.html Sent from the Pharo Smalltalk mailing list archive at Nabble.com.
Re: [Pharo-project] TxTextMorph based on new text model
Denis Kudriashov wrote I upload new version of TxText with new TxTextMorph Denis, thank you for taking this on! This is /so/ important. There are many times in my experiments with reinventing the tools when I've gotten confused and frustrated by the way text / editors work and chosen to revert to a more standard way of doing things. Two things: 1. Have you read about the experiments from VPRI? There is even an active essay where you can see each rule being applied individually 2. Have you considered growth as text is typed in? The current hold the width and grow down approach is very poor in certain applications. There was a growable version that increased to a maximum length, but it was very hacky due to the complexity of hooking into the existing objects. My point is, it would be great to be able to plugin different strategies here. Thanks for tackling this urgent and complicated topic! Sean -- View this message in context: http://forum.world.st/TxTextMorph-based-on-new-text-model-tp4663219p4664903.html Sent from the Pharo Smalltalk mailing list archive at Nabble.com.
Re: [Pharo-project] TxTextMorph based on new text model
I don't. Do you have link? Here is the paper: http://www.vpri.org/pdf/m2010002_lobjects.pdf And you can download the image with the actual active essay from http://tinlizzie.org/lesserphic2/Text%20Field%20for%20LObject.zip
Re: [Pharo-project] TxTextMorph based on new text model
On Jan 23, 2013, at 1:34 PM, Sean P. DeNigris wrote: Thanks for tackling this urgent and complicated topic! + 1000 Stef
Re: [Pharo-project] TxTextMorph based on new text model
I uploaded new version with refactored layout code and new tests. TxText tests now uses Mocketry framework. I very hope you will enjoy it. Mock objects to me is main tool to design and implement flexible object systems. And Mocketry simplifies mock objects technique very much. See announcement about new version of Mocketry. Best regards Denis 2013/1/19 Stéphane Ducasse stephane.duca...@inria.fr This is really nice. Tristan started to look at what you are doing because we proposed him to enhance textModel as part of an internship with us. Stef On Jan 18, 2013, at 9:30 PM, Denis Kudriashov wrote: Hello. I publish configuration at TxText repository based on proposed repackaging. 2013/1/15 Camillo Bruni camillobr...@gmail.com On 2013-01-15, at 12:44, Denis Kudriashov dionisi...@gmail.com wrote: Yes. I want to do it. But today I busy. Tomorrow I hope I can make it. no hurry :) I set up the jenkins build, it will trigger as soon as you push the configuration :) I actually want to split package to TxText-Model, TxText-Layout, TxText-UI, TxTextTests-Model, TxTextTests-Layout nice!
Re: [Pharo-project] TxTextMorph based on new text model
This is really nice. Tristan started to look at what you are doing because we proposed him to enhance textModel as part of an internship with us. Stef On Jan 18, 2013, at 9:30 PM, Denis Kudriashov wrote: Hello. I publish configuration at TxText repository based on proposed repackaging. 2013/1/15 Camillo Bruni camillobr...@gmail.com On 2013-01-15, at 12:44, Denis Kudriashov dionisi...@gmail.com wrote: Yes. I want to do it. But today I busy. Tomorrow I hope I can make it. no hurry :) I set up the jenkins build, it will trigger as soon as you push the configuration :) I actually want to split package to TxText-Model, TxText-Layout, TxText-UI, TxTextTests-Model, TxTextTests-Layout nice!
Re: [Pharo-project] TxTextMorph based on new text model
Hello. I publish configuration at TxText repository based on proposed repackaging. 2013/1/15 Camillo Bruni camillobr...@gmail.com On 2013-01-15, at 12:44, Denis Kudriashov dionisi...@gmail.com wrote: Yes. I want to do it. But today I busy. Tomorrow I hope I can make it. no hurry :) I set up the jenkins build, it will trigger as soon as you push the configuration :) I actually want to split package to TxText-Model, TxText-Layout, TxText-UI, TxTextTests-Model, TxTextTests-Layout nice!
Re: [Pharo-project] TxTextMorph based on new text model
Denis, could you create a ConfigurationOfTxText? That would greatly simplify the creation of a build job on jenkins! On 2013-01-13, at 22:39, Camillo Bruni camillobr...@gmail.com wrote: I added a new jenkins job: https://ci.inria.fr/rmod/job/TxText/ currently inactive/broken, we will dive into it tomorrow ;) On 2013-01-13, at 22:26, Stéphane Ducasse stephane.duca...@inria.fr wrote: thanks denis for pushing that Stef Hello. I upload new version of TxText with new TxTextMorph which can show TxTextModel (http://www.smalltalkhub.com/#!/~sig/TxText ). See class side examples. Implementation details: TxTextMorph has textLayout instance variable which contains full precomputed information to draw text on screen. TxTextLayout contains collection of TxTextLine. TxTextLine contains collection of span objects (from text model) and offset with extent required for drawing lines (with right align for example). There are TxTextLayoutStrategy hierarchy responsible for building specific text layout objects: • TxSimpleTextLayoutStrategy build layout with actual text lines which text model contains • TxWrapTextStrategy build layout with lines which satisfied preferredExtent (given from text morph bounds) When text morph accepts new text model It asks layoutStrategy to build new layout. Then align selector applyed to layout. So text can be placed left to right, centered or right to left. Morph drawing method very simple: TxTextMorphdrawOn: aCanvas textLayout drawTextOn: aCanvas at: self position TxTextLayoutdrawTextOn: aCanvas at: aPoint | topOffset linePosition | topOffset := 0. lines do: [:eachLine | linePosition := aPoint x @ (aPoint y + topOffset). eachLine drawOn: aCanvas at: linePosition. topOffset := topOffset + eachLine height. ] TxTextLinedrawOn: aCanvas at: aPoint spans do: [:each | each drawOn: aCanvas at: aPoint + offset ] At the end TxCharactersSpan draw contents on canvas: TxCharactersSpan drawOn: aCanvas at: aPoint aCanvas drawString: characters at: aPoint font: (self getAttribute: TxFontAttribute) color: (self getAttribute: TxColorAttribute) And with Athens api text attributes can be not hardcoded: TxCharactersSpan drawAthensOn: aCanvas at: aPoint attributes applyOn: aCanvas. aCanvas pathTransform translateX: aPoint x Y: aPoint y. aCanvas drawString: characters Questions: Now text alignment (like centering) is property of TxTextMorph. So it global property of full text layout. But how such attribute can be applied to specific line? TxModel is list of spans. And each span object contains characters with same text attributes like font or color. Text alignment can be such attribute too. Do you think it should be attribute of all spans from single line? Or it should be only attribute of TxLineSeparator span? What your idea? Future: Next plan: cursor navigation, text selection and editing features. And of course tests, sorry I not start with tests now. I wait your comments , ideas and questions. Maybe you don't like my approach. I want to know why. I really want clean and object solution for text stuff in pharo.
Re: [Pharo-project] TxTextMorph based on new text model
Yes. I want to do it. But today I busy. Tomorrow I hope I can make it. I actually want to split package to TxText-Model, TxText-Layout, TxText-UI, TxTextTests-Model, TxTextTests-Layout 2013/1/15 Camillo Bruni camillobr...@gmail.com Denis, could you create a ConfigurationOfTxText? That would greatly simplify the creation of a build job on jenkins! On 2013-01-13, at 22:39, Camillo Bruni camillobr...@gmail.com wrote: I added a new jenkins job: https://ci.inria.fr/rmod/job/TxText/ currently inactive/broken, we will dive into it tomorrow ;) On 2013-01-13, at 22:26, Stéphane Ducasse stephane.duca...@inria.fr wrote: thanks denis for pushing that Stef Hello. I upload new version of TxText with new TxTextMorph which can show TxTextModel (http://www.smalltalkhub.com/#!/~sig/TxText ). See class side examples. Implementation details: TxTextMorph has textLayout instance variable which contains full precomputed information to draw text on screen. TxTextLayout contains collection of TxTextLine. TxTextLine contains collection of span objects (from text model) and offset with extent required for drawing lines (with right align for example). There are TxTextLayoutStrategy hierarchy responsible for building specific text layout objects: • TxSimpleTextLayoutStrategy build layout with actual text lines which text model contains • TxWrapTextStrategy build layout with lines which satisfied preferredExtent (given from text morph bounds) When text morph accepts new text model It asks layoutStrategy to build new layout. Then align selector applyed to layout. So text can be placed left to right, centered or right to left. Morph drawing method very simple: TxTextMorphdrawOn: aCanvas textLayout drawTextOn: aCanvas at: self position TxTextLayoutdrawTextOn: aCanvas at: aPoint | topOffset linePosition | topOffset := 0. lines do: [:eachLine | linePosition := aPoint x @ (aPoint y + topOffset). eachLine drawOn: aCanvas at: linePosition. topOffset := topOffset + eachLine height. ] TxTextLinedrawOn: aCanvas at: aPoint spans do: [:each | each drawOn: aCanvas at: aPoint + offset ] At the end TxCharactersSpan draw contents on canvas: TxCharactersSpan drawOn: aCanvas at: aPoint aCanvas drawString: characters at: aPoint font: (self getAttribute: TxFontAttribute) color: (self getAttribute: TxColorAttribute) And with Athens api text attributes can be not hardcoded: TxCharactersSpan drawAthensOn: aCanvas at: aPoint attributes applyOn: aCanvas. aCanvas pathTransform translateX: aPoint x Y: aPoint y. aCanvas drawString: characters Questions: Now text alignment (like centering) is property of TxTextMorph. So it global property of full text layout. But how such attribute can be applied to specific line? TxModel is list of spans. And each span object contains characters with same text attributes like font or color. Text alignment can be such attribute too. Do you think it should be attribute of all spans from single line? Or it should be only attribute of TxLineSeparator span? What your idea? Future: Next plan: cursor navigation, text selection and editing features. And of course tests, sorry I not start with tests now. I wait your comments , ideas and questions. Maybe you don't like my approach. I want to know why. I really want clean and object solution for text stuff in pharo.
Re: [Pharo-project] TxTextMorph based on new text model
On 2013-01-15, at 12:44, Denis Kudriashov dionisi...@gmail.com wrote: Yes. I want to do it. But today I busy. Tomorrow I hope I can make it. no hurry :) I set up the jenkins build, it will trigger as soon as you push the configuration :) I actually want to split package to TxText-Model, TxText-Layout, TxText-UI, TxTextTests-Model, TxTextTests-Layout nice!
Re: [Pharo-project] TxTextMorph based on new text model
Wow.. this is a huge progress! Sorry i was busy with other stuff and had no time to look at your code. On 13 January 2013 20:54, Denis Kudriashov dionisi...@gmail.com wrote: Hello. I upload new version of TxText with new TxTextMorph which can show TxTextModel (http://www.smalltalkhub.com/#!/~sig/TxText ). See class side examples. Implementation details: TxTextMorph has textLayout instance variable which contains full precomputed information to draw text on screen. TxTextLayout contains collection of TxTextLine. TxTextLine contains collection of span objects (from text model) and offset with extent required for drawing lines (with right align for example). There are TxTextLayoutStrategy hierarchy responsible for building specific text layout objects: TxSimpleTextLayoutStrategy build layout with actual text lines which text model contains TxWrapTextStrategy build layout with lines which satisfied preferredExtent (given from text morph bounds) When text morph accepts new text model It asks layoutStrategy to build new layout. Then align selector applyed to layout. So text can be placed left to right, centered or right to left. Morph drawing method very simple: TxTextMorphdrawOn: aCanvas textLayout drawTextOn: aCanvas at: self position TxTextLayoutdrawTextOn: aCanvas at: aPoint | topOffset linePosition | topOffset := 0. lines do: [:eachLine | linePosition := aPoint x @ (aPoint y + topOffset). eachLine drawOn: aCanvas at: linePosition. topOffset := topOffset + eachLine height. ] TxTextLinedrawOn: aCanvas at: aPoint spans do: [:each | each drawOn: aCanvas at: aPoint + offset ] At the end TxCharactersSpan draw contents on canvas: TxCharactersSpan drawOn: aCanvas at: aPoint aCanvas drawString: characters at: aPoint font: (self getAttribute: TxFontAttribute) color: (self getAttribute: TxColorAttribute) And with Athens api text attributes can be not hardcoded: TxCharactersSpan drawAthensOn: aCanvas at: aPoint attributes applyOn: aCanvas. aCanvas pathTransform translateX: aPoint x Y: aPoint y. aCanvas drawString: characters Questions: Now text alignment (like centering) is property of TxTextMorph. So it global property of full text layout. But how such attribute can be applied to specific line? TxModel is list of spans. And each span object contains characters with same text attributes like font or color. Text alignment can be such attribute too. Do you think it should be attribute of all spans from single line? Or it should be only attribute of TxLineSeparator span? What your idea? Well, there is two approaches: a per-line attribute can be a special span at the beginning at line, or it can be an attribute. Both has pros and cons, however. In case of span, it needs to be dealt properly with text editing/navigation. In case of attribute(s), this attribute is really per line (or better to say, per paragraph) and putting it into each span seems like superfluous. IMO, i would go for a simplest model: the capability like text alignment (left/center/right) per line, is kind of overkill for our little world. I mean, it would be nice to have, but look at our tools: where are they used? Nowhere. So i would not focus on it right now, and having a global attribute seems like a good solution right now. Future: Next plan: cursor navigation, text selection and editing features. And of course tests, sorry I not start with tests now. don't forget about tests. We started writing a model by implementing tests first, because we didn't wanted an implementation to dictate how things should be used. I wait your comments , ideas and questions. Maybe you don't like my approach. I want to know why. I really want clean and object solution for text stuff in pharo. -- Best regards, Igor Stasenko.
Re: [Pharo-project] TxTextMorph based on new text model
Igor do not think that because our tools do not use anything, we do not need good text support. Moose is struggling with the limits of the current textmodel. We should offer solutions to people not just to edit methods. Stef On Jan 13, 2013, at 9:51 PM, Igor Stasenko wrote: Wow.. this is a huge progress! Sorry i was busy with other stuff and had no time to look at your code. On 13 January 2013 20:54, Denis Kudriashov dionisi...@gmail.com wrote: Hello. I upload new version of TxText with new TxTextMorph which can show TxTextModel (http://www.smalltalkhub.com/#!/~sig/TxText ). See class side examples. Implementation details: TxTextMorph has textLayout instance variable which contains full precomputed information to draw text on screen. TxTextLayout contains collection of TxTextLine. TxTextLine contains collection of span objects (from text model) and offset with extent required for drawing lines (with right align for example). There are TxTextLayoutStrategy hierarchy responsible for building specific text layout objects: TxSimpleTextLayoutStrategy build layout with actual text lines which text model contains TxWrapTextStrategy build layout with lines which satisfied preferredExtent (given from text morph bounds) When text morph accepts new text model It asks layoutStrategy to build new layout. Then align selector applyed to layout. So text can be placed left to right, centered or right to left. Morph drawing method very simple: TxTextMorphdrawOn: aCanvas textLayout drawTextOn: aCanvas at: self position TxTextLayoutdrawTextOn: aCanvas at: aPoint | topOffset linePosition | topOffset := 0. lines do: [:eachLine | linePosition := aPoint x @ (aPoint y + topOffset). eachLine drawOn: aCanvas at: linePosition. topOffset := topOffset + eachLine height. ] TxTextLinedrawOn: aCanvas at: aPoint spans do: [:each | each drawOn: aCanvas at: aPoint + offset ] At the end TxCharactersSpan draw contents on canvas: TxCharactersSpan drawOn: aCanvas at: aPoint aCanvas drawString: characters at: aPoint font: (self getAttribute: TxFontAttribute) color: (self getAttribute: TxColorAttribute) And with Athens api text attributes can be not hardcoded: TxCharactersSpan drawAthensOn: aCanvas at: aPoint attributes applyOn: aCanvas. aCanvas pathTransform translateX: aPoint x Y: aPoint y. aCanvas drawString: characters Questions: Now text alignment (like centering) is property of TxTextMorph. So it global property of full text layout. But how such attribute can be applied to specific line? TxModel is list of spans. And each span object contains characters with same text attributes like font or color. Text alignment can be such attribute too. Do you think it should be attribute of all spans from single line? Or it should be only attribute of TxLineSeparator span? What your idea? Well, there is two approaches: a per-line attribute can be a special span at the beginning at line, or it can be an attribute. Both has pros and cons, however. In case of span, it needs to be dealt properly with text editing/navigation. In case of attribute(s), this attribute is really per line (or better to say, per paragraph) and putting it into each span seems like superfluous. IMO, i would go for a simplest model: the capability like text alignment (left/center/right) per line, is kind of overkill for our little world. I mean, it would be nice to have, but look at our tools: where are they used? Nowhere. So i would not focus on it right now, and having a global attribute seems like a good solution right now. Future: Next plan: cursor navigation, text selection and editing features. And of course tests, sorry I not start with tests now. don't forget about tests. We started writing a model by implementing tests first, because we didn't wanted an implementation to dictate how things should be used. I wait your comments , ideas and questions. Maybe you don't like my approach. I want to know why. I really want clean and object solution for text stuff in pharo. -- Best regards, Igor Stasenko.
Re: [Pharo-project] TxTextMorph based on new text model
thanks denis for pushing that Stef Hello. I upload new version of TxText with new TxTextMorph which can show TxTextModel (http://www.smalltalkhub.com/#!/~sig/TxText ). See class side examples. Implementation details: TxTextMorph has textLayout instance variable which contains full precomputed information to draw text on screen. TxTextLayout contains collection of TxTextLine. TxTextLine contains collection of span objects (from text model) and offset with extent required for drawing lines (with right align for example). There are TxTextLayoutStrategy hierarchy responsible for building specific text layout objects: • TxSimpleTextLayoutStrategy build layout with actual text lines which text model contains • TxWrapTextStrategy build layout with lines which satisfied preferredExtent (given from text morph bounds) When text morph accepts new text model It asks layoutStrategy to build new layout. Then align selector applyed to layout. So text can be placed left to right, centered or right to left. Morph drawing method very simple: TxTextMorphdrawOn: aCanvas textLayout drawTextOn: aCanvas at: self position TxTextLayoutdrawTextOn: aCanvas at: aPoint | topOffset linePosition | topOffset := 0. lines do: [:eachLine | linePosition := aPoint x @ (aPoint y + topOffset). eachLine drawOn: aCanvas at: linePosition. topOffset := topOffset + eachLine height. ] TxTextLinedrawOn: aCanvas at: aPoint spans do: [:each | each drawOn: aCanvas at: aPoint + offset ] At the end TxCharactersSpan draw contents on canvas: TxCharactersSpan drawOn: aCanvas at: aPoint aCanvas drawString: characters at: aPoint font: (self getAttribute: TxFontAttribute) color: (self getAttribute: TxColorAttribute) And with Athens api text attributes can be not hardcoded: TxCharactersSpan drawAthensOn: aCanvas at: aPoint attributes applyOn: aCanvas. aCanvas pathTransform translateX: aPoint x Y: aPoint y. aCanvas drawString: characters Questions: Now text alignment (like centering) is property of TxTextMorph. So it global property of full text layout. But how such attribute can be applied to specific line? TxModel is list of spans. And each span object contains characters with same text attributes like font or color. Text alignment can be such attribute too. Do you think it should be attribute of all spans from single line? Or it should be only attribute of TxLineSeparator span? What your idea? Future: Next plan: cursor navigation, text selection and editing features. And of course tests, sorry I not start with tests now. I wait your comments , ideas and questions. Maybe you don't like my approach. I want to know why. I really want clean and object solution for text stuff in pharo.
Re: [Pharo-project] TxTextMorph based on new text model
I added a new jenkins job: https://ci.inria.fr/rmod/job/TxText/ currently inactive/broken, we will dive into it tomorrow ;) On 2013-01-13, at 22:26, Stéphane Ducasse stephane.duca...@inria.fr wrote: thanks denis for pushing that Stef Hello. I upload new version of TxText with new TxTextMorph which can show TxTextModel (http://www.smalltalkhub.com/#!/~sig/TxText ). See class side examples. Implementation details: TxTextMorph has textLayout instance variable which contains full precomputed information to draw text on screen. TxTextLayout contains collection of TxTextLine. TxTextLine contains collection of span objects (from text model) and offset with extent required for drawing lines (with right align for example). There are TxTextLayoutStrategy hierarchy responsible for building specific text layout objects: • TxSimpleTextLayoutStrategy build layout with actual text lines which text model contains • TxWrapTextStrategy build layout with lines which satisfied preferredExtent (given from text morph bounds) When text morph accepts new text model It asks layoutStrategy to build new layout. Then align selector applyed to layout. So text can be placed left to right, centered or right to left. Morph drawing method very simple: TxTextMorphdrawOn: aCanvas textLayout drawTextOn: aCanvas at: self position TxTextLayoutdrawTextOn: aCanvas at: aPoint | topOffset linePosition | topOffset := 0. lines do: [:eachLine | linePosition := aPoint x @ (aPoint y + topOffset). eachLine drawOn: aCanvas at: linePosition. topOffset := topOffset + eachLine height. ] TxTextLinedrawOn: aCanvas at: aPoint spans do: [:each | each drawOn: aCanvas at: aPoint + offset ] At the end TxCharactersSpan draw contents on canvas: TxCharactersSpan drawOn: aCanvas at: aPoint aCanvas drawString: characters at: aPoint font: (self getAttribute: TxFontAttribute) color: (self getAttribute: TxColorAttribute) And with Athens api text attributes can be not hardcoded: TxCharactersSpan drawAthensOn: aCanvas at: aPoint attributes applyOn: aCanvas. aCanvas pathTransform translateX: aPoint x Y: aPoint y. aCanvas drawString: characters Questions: Now text alignment (like centering) is property of TxTextMorph. So it global property of full text layout. But how such attribute can be applied to specific line? TxModel is list of spans. And each span object contains characters with same text attributes like font or color. Text alignment can be such attribute too. Do you think it should be attribute of all spans from single line? Or it should be only attribute of TxLineSeparator span? What your idea? Future: Next plan: cursor navigation, text selection and editing features. And of course tests, sorry I not start with tests now. I wait your comments , ideas and questions. Maybe you don't like my approach. I want to know why. I really want clean and object solution for text stuff in pharo.
