目前字體設計都是以拉曲線（curve）形式來進行，這裡curve 是指字體的輪廓線（outline），這讓調整效率偏低，如一捺要變窄，則要左右邊的curve 都調整。這是字體設計師許瀚文​  Julius Hui 的示範 ：

雖然 GlyphsApp 有所謂‘Smart Component’ 功能可以先把同一個部件的幾個不同形態設好再interpolate得到中間形態，但始終還是用 outline 來定義，有時interpolate 出來還是有點怪怪的。

筆者覺得這尤其不配合中文書法體的製作：書法字本來就是一筆一筆寫出來，但掃描進電腦也是一大堆curve點，要簡化和一條條曲線調整，筆劃也不能自動分離來方便修改。以下是 Justfont 的示範：

近年有歐洲人提出用 skeleton-based 的辦法，革新傳統的造字系統，這與筆者的想法非常接近：

這樣產生的中文字型，我們當然可以更改筆的粗度、水分、紙材等參數以求不同的效果，但問題是不好嵌入到現在的outline font 系統，因為飛白、墨色變化等東西在傳統的outline font 系統難以表現。筆者跟字體設計師 柯熾堅老師 Sammy Or 前輩談過，他就很喜歡我們的墨色變化呢！

Outline-based  font 有個好處，就是簡單，方便用於像Postscript 那樣的頁面描述語言裏。最初鐳射打印機也配備晶片運行自己的rasterizer，可以直接執行Postscript 指令。現在電腦運算力強，rasterization   都在電腦裡用軟件實現， 打印機則不必自備rasterizer。

而筆者現在的proposal，用虛擬毛筆畫出stroke-based 字型，是基於利用現代電腦的GPU 運算力。現代電腦的GPU在這20年內進步很快，現在即便是 integrated GPU的運算力也追上來了，故筆者認爲是可能的。當然具體軟件工程，仍有待進一步優化實現：因爲目前Expresii 要把字寫每筆出來，有寫的‘過程’，畫出一個字會較慢。日後，可能要開發些parallel 筆劃等的演算法，加快rendering速度，才能配上電腦屏幕顯示和打印的應用。目前Expresii 畫了一個字，只要保留intermediate 結果，其rendering engine 是可以很快得render出不同大小的。所以cache 系統也要考慮，做出優化的新字型系統。如最終不夠快做内文顯示，其實也用於標題字款，反正書法風的字，比較適合標題而非内文。

一般硬筆的藝術性比毛筆差，因為筆觸變化沒那麼大。但現在電子筆透過軟件，藝術性變得媲美甚至超越毛筆。
​
筆者很希望​學校考慮推廣電腦書法教學。我們辦學，是為準備孩子應付未來30年的挑戰。現在電子產品越來越流行，電子書法必然會發展出來的。未來的人會更多時間用電子筆，就像現代人用硬筆多於毛筆一樣。來，讓我們一起參與這場書法革命！

自從西方硬筆傳入東方，我們日常書寫已棄毛筆取硬筆，硬筆之普及也讓我們發展出‘硬筆書法’。​嚴格來說，現在的電子筆是硬筆的一種。試想想，電子產品之應用也越催普及，電腦書法乃必然發展出來。而筆者一直努力深耕，開發書法水墨軟件Expresii，目前已經可寫出比美毛筆書法的作品，毛筆多變之特性比任何其他軟件都好。

電腦書法（中國大陸叫‘數字書法’；台灣叫‘數位書法’）之藝術性是介乎於毛筆跟硬筆之間。數位有硬筆 的方便，但也只有約一毫米的按壓距程，跟真毛筆約一寸有差。

以下是在微軟的Surface Book 2 上書寫示範：

但蔡生覺得筆還不完善，我說硬件方面我無能為力，我只做軟件。他則叮囑我要跟電子筆製造商一起完善電子書法體驗。其實我多年也有接觸硬件商Wacom 給意見，但公司太大，意見是否真的傳達到決策者則不得而知。我也嘗試跟大陸品牌Huion 、友基等聯繫，可惜更難接觸。大概他們都忙於佔領能賺錢的數位板市場，沒空照顧電腦書法。

水墨作品能複製嗎？可以，有榮寶齋的木板水印工藝。雖然這工藝被譽為‘絕活’，但是要人手把原圖分成‘圖層’（所以非所有畫作都能複製），再把圖層雕刻於木板上，再人手於木板上色一板一板的印圖，工序非常複雜。但如果是數位作品，圖層固然有，當然複製或網絡傳送，也可無損​。

宣紙上的墨跡很難修改，所以水墨畫被譽為世上最'真誠'的畫種。但就算名家如徐悲鴻，有時也希望可以修改：榮寶齋曾替​徐悲鴻以 木板水印方法複製一幅奔馬圖，​​徐悲鴻覺得馬腿畫太長了，問可否於複製品中修改呢。在電腦世界，數位作品是可以無縫修改。有修改的能力，你可以不用，但也難否定這能力的用處。

繪畫過程是可以記錄下來，重複演示。這其實對教學很有幫助，因爲東西本身已經是數位格式，要了解過程不需要用攝影機拍著老師作畫。繪畫過程只記錄用筆用墨的數據，檔案也非常小，方便網絡傳送。

電腦的出現，并不代表我們摒棄傳統。為了迎合電腦時代，電子書法的開發，正正是需要我們去耕耘，把傳統延伸到數碼領域。

筆者推廣電子書法時，通常放眼年輕一代，因​老一輩手熟於傳統毛筆，通常會要求電子筆跟傳統毛筆做到一模一樣，但這其實受硬件限制，目前仍難以實現*。目前硬件生產商較着重發展模仿西方硬筆，希望日後硬件商多多跟我們交流合作，一起完善電子書法體驗。

教育部門如認同筆者愚見，也希望也能撥出資源，一起讓電腦書法普及起來！

*  全球最大電子筆生產商Wacom 乃日本公司，日本人當然有想過要電子筆模仿毛筆，但這30年歷史的公司仍未做有效模仿毛筆的電子筆（不是只是把毛束當一個點而已，如   Sensu Brush）出來，可想這不是那麼容易的事情。真筆沾水用在電腦繪畫有LightStrokes，但其還有問題：1.沒有cursor 你要猜下筆位置。2. 濕筆在玻璃上滑動完全不像在紙上寫字般，寫書法的話比較難操控。這些問題仍有待解決。

It has been one year since the Microsoft Surface Pro 7 was released.   We got ourselves an i7 model to test with. We've had it for about a month now and it has been very responsive.

The following is a quick test on its performance. As you can see, it allows fluid digital watercolor in Expresii. In case you can't afford the i7 model, you can still get by with the i5 model, but  you may want to use the   Fast Mode   for more responsiveness.

Did some calligraphy test too:

Don't have the original Surface Pen with us right now, so we picked up a Surface Pen alternative in these tests. 

Finally  we'd like to show you some sneak peek at some latest development in   ink-painting-style animation (水墨動畫) that we are working on.   Follow our animator collaborator's Instagram  to learn more. Their work is so cool & cute at the same time!

​And yes, Surface Pro is used in producing this animation, in case you wonder.   ​​(・ωｰ)～☆

Perhaps  the highlight of the Lenovo Yoga Duet 7i is its support for the brand new Lenovo E-Color Pen.  Among all the pressure-sensitive styli for iPads, Windows or Android devices, the   Lenovo E-Color Pen is the first that can capture colors from the real world.  Recently, the Apple Pencil was rumored to add such a feature given they filed a related patent application. However, It's not likely Apple would be granted such a patent, as suggested by Jeremy Shu, CEO of Ufro Inc, the company that provides the color capture technology in the   E-Color Pen . 

The Lenovo E-Color Pen is a rechargeable Wacom AES pen. Its USB-C charging port is hidden behind the color capture module, which unplugs from the top of the pen.  The pen is pressure sensitive and drives the cursor when hovering. It doesn't support  tilt sensing, but you can use one of the two side buttons to adjust brush tilt in Expresii. 

​The pen is not magnetic like the Surface Pen, so you can't just stick it to the side of the tablet. Previously Lenovo supplies  holder for their active pens that plugs into USB-A ports of the tablets, but now they switched to USB-C for the Yoga Duet 7i so you will need to find another solution if you want to keep it attached e.g. this pen sleeve  on Amazon, or the same thing on TMall of China for half the price. 

Currently our app Expresii is one of the select apps that natively support the E-Color Pen color capture function.  Its watercolor simulation is a good reason  for anyone to use it for showing the capture capability beautifully.  When you pick a yellow and a cyan from the real world, the virtual paint mixes together to give a nice green and Expresii's watercolor flow further mingles the paint with gorgeous flow patterns in very high resolution.  Expresii supports Ufro's   Mozbii pen since 2018  and we thank Wacom for linking us up leading to   hardware and software innovations working well together.

The following is a video showing general color picking  and the use of the pen for Eastern calligraphy on the Yoga Duet 7i. The machine used in the i5 model, but it's already fast enough for using Expresii. There's the i7 option that gives even better performance for you to choose from.

I came from the Surface Pro family, and I really prefer the keyboard of the Duet 7i being able to operate via bluetooth when detached. It's good that Lenovo is including both the keyboard and the E-Color pen, at least in the markets of Hong Kong and the Philippines, instead of needing customers to   fork out    another   USD 90 to 160 for a keyboard cover  and   USD 99 for the official Surface Pen.  There're cheaper aftermarket alternatives for both items (like these pen alternatives), but consumers need to shop around separately. The Yoga Duet 7i is called Yoga Duet 2020    in the Chinese market, and a normal Active pen instead of the E-Color Pen is included.

Expresii  receives colors from Color King, the proxy software that sends the captured colors to supported apps.  Our Expresii not only can directly receive colors from Color King, but it also offers you the option to auto-load single or multiple-colors into the virtual brush. This is a unique feature made possible by the native support for multi-color loading in Expresii.   As demonstrated in the above video, you could pick a few colors in sequence to make a gradient in the brush. You then can make strokes with such a gradient for even more interesting marks!

We  further demo coloring a piece of ink work using the E-Color Pen.   In this demo, we celebrate  brush stroke economy. We appreciate watercolor having a life of its own. From the thumbnail, you may not be able to appreciate the simulation quality so we urge you to watch the video:

The following video shows the performance of color capture and making strokes on the i5 version of the Yoga Duet 7i.  The color transfer can be immediate. In the above videos, most of the clips are played back at 2x speed up for editing purpose. The following video shows you the performance in real time.

​Our app uses GPU for rendering and flow simulation, so it's often the GPU being the bottleneck.  If you find it too slow on your machine, we can still enable Quick Stroke Mode (Fast Mode), and Expresii would be more responsive as you stroke. If you're on Win10, it's easy to download this Store Demo version of Expresii for you to test out the performance.

How accurate is the color capture? I'd say pretty accurate, as you can see from our demo videos. I tried picking the neon   orange from my sport shirt and the color captured was obviously off. But other than difficult situations like that, it's pretty accurate for the most part.

We appreciate   the startup   Ufro Inc   bringing low-cost color capture tech to the masses. Color sampling devices used to be rather expansive, and only specialized  people would buy them. FYI, you can also order Ufro's standalone color picker InstaPick for as low as USD 60.   We also appreciate   Wacom and   Lenovo for adopting the innovation.

We hope that the Lenovo E-Color Pen would be supported on future pen-enabled machines from Lenovo.  They just announced  the Yoga 9i, which uses Intel’s new and much improved Intel Xe integrated graphics of the 11th Gen CPU. We also wish Lenovo would opt for tilt sensing for their coming pen models. The future looks bright for creative professionals!

🍊🧧 🏮   Best Wishes for the  Year Of The Pig  🐖  2019 瑞豬 己亥 迎春     🏮​🧧🌱

Ambigram 瑞豬   ⇔   己亥 迎春
See it displayed on Surface Pro's / interactively    

We designed the ambigram [瑞豬 ⇔   己亥 迎春]​ using Expresii's new quarter mode to celebrate the New Year of the Pig. T he year 2019 is marked as  [己亥]  in the lunar calendar.  [迎春] means welcoming spring;     [瑞豬] pig that brings luck.    Paper Cut is good for showing flip-type ambigrams since you can easily flip the paper to show different sides of the design.

It's common to display lanterns for  Lunar New Year.  We therefore try our hands on making a few lanterns featuring our ambigram greetings. We wanted to have a blend of tradition  & tech and also make the piece interactive so we made an attempt to embed    QR code  into the design  - not just any QR code but ones that can be read from both sides carrying different messages just like an ambigram!   To complete such a design, artist ability alone is not enough. 

To make our two-sided QR code,  we  asked   Prof. Tim Leung   of HKUST to help with the number crunching.   Specifically, we need to write a computer program to untie the knot in producing two-sided QR Codes.   

​'​We have a UG student working on this problem. It's a good training for the student, which involves math and  (computer) coding​,' said Prof. Leung.  Our Dr. Nelson Chu, designer behind the ambigrams and lanterns, is an alumnus of HKUST and hopes to get current HKUST students inspired by interesting projects like this.  ’This is a typical real-world problem we need to solve everyday. In contrast, usually  clear instructions are given in a school assignment. But now one needs to be critical and be able to judge the correctness in the information gathered', said Dr. Chu.   'There may be more solution to one problem, and some hidden issues yet to be solved.'

And here comes the Moment of Truth - see if the two-sided QR Codes work in the following video:      (*ﾟﾛﾟ)

And if you are to try  out our 2-sided QR codes, note that some QR code scanners would only give the message  from one side because they would flip the input automatically.  We use this scanner  on Android, which can read the two messages.

This lantern creation is a perfect example of STEAM ( STEM+Art) projects.   Apart from trying to get involved in multi-discipline activities, we strongly encourage students to learn computer programming regardless their majors. Being able to program a computer is empowering. You don't need to wait for someone to make a program suitable for your needs, you can just create one ​whenever creativity strikes!    Being able to make the first move and create something never existed before makes you a leader rather than a follower.

“近年，教育界提出新的「STEAM」框架，亦即在原本的「STEM」加入藝術（Art）的意涵，強調未來的學生應培養跨領域素養和能力。” (wikipedia)

STEM 是美國先提倡，然後香港、台灣等地跟隨。我們其實一直做的就是STEAM的工作：從一開始用 物理原理 模擬 毛筆，用 流體力學 做 數碼水墨，到現在開發 中文 翻轉字 (ambigramアンビグラム) 工具，全部都把藝術、文化、科技等結合，做出前所未有的新產品。我們非常歡迎各學校共同辦好STEAM 教育，讓我們的學生Future Ready，迎接未來的挑戰！東方文化有很多值得發展的地方，希望一天我們是領導者，而不是跟隨者。╭( ･ㅂ･)و )))​

P.S. We'll post making-of for the laterns in a later blog entry. Stay tuned. 

​'Flip' Icon made by Vaadin ​   from www.flaticon.com

We were excited ever since the first Surface Book came out in 2015, since it gave the option for a discrete GPU.​ Now we have a chance to test with a Surface Book 2, thanks to Microsoft for providing the hardware for testing.

We are provided with the 13.5" model. Coming from the 12" Surface Pro, I like the bigger screen size.   The hardware feels really solid and clean. And of course, with an nvidia GTX 1050, we get very good performance, although it gets a bit hot and the fan would kick on. 

See the calligraphy process video in Youtube:

Lunar new year day was  16th of Feb, 2018.   We wish you all the best for the new year  of the dog!

Now it's being a tradition we play with the Chinese character for the year.  This year, we play with the character 狗, which means dog:

Recently, ambigram  is popular around East Asia, so we make one that reads dog and shows a dog 90-deg turned.  

​And notice how we use pen tilt to make organic marks.

Chinese characters give you so much room for imagination!  We can't stop playing with them!
​大家快來寫數位書法，漢字給你太多想像了！

Only Expresii gives you this level of expression with brush and ink! 

Earlier this month, our Dr. Nelson Chu, along with  two more  alumni ​, was invited to speak in an alumni sharing session by HKUST.   You can review the whole sharing  here.   Nelson showed our  ground-breaking app Expresii on a tablet computer to the audience.   

During the Q&A section, Nelson was asked   to comment on how to deal with people saying digital art is not real art. To answer  this, let's first assume people don't regard digital art as real art because they think operations like undo and redo   mean   cheating. Let's here what Nelson has to say:

'Long time ago when the Western fountain pen got introduced to the East, people might say "pen calligraphy" is not calligraphy. Only brush calligraphy is. But now people accept that pen calligraphy is also calligraphy' said Nelson.

Nelson is a firm believer of digital calligraphy.  See how he does digital calligraphy with his own tool Expresii: 

From the above videos, you see how undo's and redo's allowed more flexibility and save time  to create the perfect design without wasting paper.    ​(^(エ)^)

In deed, if you look at the history of writing tools in East Asia, you will see we keep adding new tools to our arsenal over the years.  If we insist that a new tool has to act exactly like what came before it, there wouldn't have been brush calligraphy in the first place because we would still be using carving knifes to write. 

​​We should really   embrace new technology   and   explore what we can do with it.

Another possible reason why people don't consider digital art real  is that they can't sell it to galleries or collectors like they do with works done in physical media.  People are concerned that artists  (along with a whole ecosystem of art dealers) can not make a living if there are no   originals  (vs. digital copies) to sell.   

To respond to this, firstly, we'd like to emphasis that artistic value is NOT market value. If we stick to the question of  whether something is real art we should  really judge it by its artistic value.   Whether it sells or not is a completely different story.   For a painting, we judge its artistic value by e.g. the use of colors or  composition, which you can also find in digital art. 

Secondly, business models can adapt to changes.  A century ago, musicians made a living by performing live. With the invention of sound recorder, musicians don't lose their job simply   because there is  a way to playback their music. Instead, a whole ecosystem of record companies & distributors came into existence. And then came the digital age, when people don't buy CD's as often.  Record companies could blame digital music making it easy to be pirated. Then Apple fights the problem by providing a way to get legit music easier than looking for pirated copies.   And if you think those big companies are paying artists  too little royalty ,  now independent   artists can sell their music, art or tutorials via sites like Gumroad with a much bigger cut,  effectively  democratizing  art selling for creators.

When Apple   introduced the Apple Pencil, I was thrilled to find out the Apple Pencil supporting tilt. Eastern calligraphy appeared two times in their launch video. The first one is writing '書'  in red (below). 

Since its early versions, Painter has been using 'dots  within a circle' as the brush footprint to give a 'bristle' effect (video below).  Procreate seems to use a similar method to do bristle effect - the dab could be a captured image instead of one generated on the fly.  Interestingly, Adobe's 3D brushes give effect similar   to what these 2D brushes give  - the 3D nature seems to be not put into good use. In fact, when Samsung's latest Galaxy Book tablet was announced, demonstrators actually had a hard time showing off the new pen tilt feature with Photoshop, because no matter how they tilted the brush, they still got strokes as if  done in 2D without tilt support. By the way,  when a brush is enlarged, why does  it start to sprinkle smaller version of itself?

In order to capture the nuance we normally get when using a real brush, we devised a more efficient 3D brush model. By efficient we mean we don't need to model it as 'individual bristles' as in Adobe's 3D brushes [1], and yet we believe we get more stroke variations than they do.  Our brush model also looks and acts more like a real brush instead of a brush made of stiff wires.  All in all, we believe our brush is the most natural and intuitive to use among all paint apps available today.

I can only recognize two characters '秋月'  from  what is written in the second appearance of Eastern calligraphy above so let's try writing the same characters in different styles in Expresii: ​​

And another demo  '筆墨'  for you.  In Expresii, every stroke has  its own character, its personality.   You can 't make the same stroke twice.

And I love doing designs like the following using Expresii.  You can do designs quickly and easily just like using a real Chinese brush.

And don't just take our words. See what Shaun Bryant has to say:

We all know that raster-based paint programs are good for stroke richness  but you can't really zoom in too much.  Adobe came up with a solution of generating vector graphics  [1] for high resolution rendering.  For this to work, you're effectively  switching entirely to their vector-based tool, namely Illustrator.  When enlarged, you see many individual polygons overlapping each other (below). Personally, I don't think it looks too pretty nor natural, not to mention the added burden of rendering thousands of polygons.  ​(๑´╹‸╹`๑)

We came up with an entirely different solution to the fat pixel problem. We can zoom in a lot, but the marks still look natural.   ​ Jony Ive ended Apple's launch video with "gives you the ability to touch a single pixel".  And here I'd like to say we give you the ability to zoom in a lot without seeing a single pixel.  (￣▽￣)ノ​

People complain  about the younger generation  being occupied by gadgets and  too few are doing traditional arts. If you are an educator involved with art or East Asian languages,  please consider joining us for this digital calligraphy  revolution. Technology  and art are not mutually exclusive. You can start teaching digital calligraphy today. Together, we'll work to revitalize this ancient art form.  Leave a comment below or message via Facebook, Twitter or whatever. Thank you!

Reference:
[1] from their paper "Industrial-Strength Painting with a Virtual Bristle Brush", 2010. [cached copy]

2017.04.30 Update:  we are informed that the piece of calligraphy was done by  Prof  王冬齡, and in the video, the shot should be showing him signing his name '冬齡'.  [ref 1] [ref 2]

Made a few animated GIF for the new year with Expresii.  

Running chicken 走雞：

Essentially these animations are done using the Overlay as onion skin.  You can also apply LightBox effect on the Overlay.  You can toggle the Overlay via  hotkeys ~ ` to alpha = 0 and 1. We output the frames to another program to do cropping or composition,  and then  feed the final frames to an online GIF maker  to make the GIFs.

The following videos shows some of the stroking process:

Finally here is a Lion Dance greeting GIF made by Rooftop Animation using Expresii (along with Photoshop, etc) for the new year: