Recent changes to support-requests

Add touch scrolling

Krzysztof Kamil Jacewicz — Tue, 13 Dec 2016 06:44:55 -0000

In the scenario when the application runs on a touch screen device, the feature of scrolling the document vertically with the touch drag is what user expects.

Additionally, when running on a screen with a very high DPI, the size of the scrollbars becomes so tiny, that using touch (fingers) to operate these scroll bars becomes very difficult.

I faced this scenarios when deploying Lazarus written applications on Meizu MX4 phone running Ubuntu Touch.

I found out an opportunity in the layout of the TSynEdit, more precisely, took advantage of the Gutter. Currently the Gutter does not make any special use of Mouse Events (OnMouseDown, OnMouseMove, OnMouseUp), and it provides enough surace area for using touch gestures on it conveniently. Especially that in a high dpi scenario I can still programatically increase TSynEdit.Font.Height which will render Gutter big enough for the scenario.

I implemented a class TTouchSynEdit which allows you to use touch gestures (fragging down/up) on the gutter for scrolling the text vertically. The behavior can be turned on/off with:
Property TTouchSynEdit.EnableTouchScrollOnGutter: Boolean;
which is set to True by default.

Attached is the source code, it is very short, please feel free to use it by either including TTouchSynEdit class in your sources or by transplanting my functionality into the TSynEdit class.

Best Regards,
Kris

#55 SynEdit very slow on long lines

Roman Kassebaum — Wed, 29 Apr 2015 13:43:04 -0000

IMHO there shouldn't be so many different libraries. Now we have one under sf and two under GitHub.

And no, it is not my own work. I already merged the sf and SynEdit/SynEdit version.

Any yes, the TurboPack version is the one that ships with XE8 and GetIt.

But if you want to maintain the other versions, it is your choice.

#55 SynEdit very slow on long lines

Roman Kassebaum — Wed, 29 Apr 2015 13:18:10 -0000

But XE8 already came out.

#55 SynEdit very slow on long lines

Bas Schouten — Wed, 29 Apr 2015 13:12:30 -0000

SynEdit/Synedit was updated when XE7 came out ... and uses the original packages setup
That doesn't mean that the packages setup of TuboPack/SynEdit is not good .. but its a different product.

#55 SynEdit very slow on long lines

Roman Kassebaum — Wed, 29 Apr 2015 13:09:57 -0000

https://github.com/SynEdit/SynEdit doesn't seem to be active any longer.

#55 SynEdit very slow on long lines

Bas Schouten — Wed, 29 Apr 2015 13:00:58 -0000

I thought it had moved to https://github.com/SynEdit/SynEdit

#55 SynEdit very slow on long lines

Roman Kassebaum — Wed, 29 Apr 2015 08:32:42 -0000

Hi Cyrille,

the SynEdit project moved to GitHub: https://github.com/TurboPack/SynEdit

--
Roman

#55 SynEdit very slow on long lines

Cyrille de Brébisson — Wed, 29 Apr 2015 06:58:04 -0000

Hello Again,

Great when users solve their own problems, isn't it?

I have 'fixed' the problem, or at least am hiding it by doing the ExpandAtWideGlyphs incrementaly, only when needed in the inner PaintLines loop (well, one level deeper).
I had to implement a nev version of ExpandAtWideGlyphs that can work incrementally to do that (based on the existing one)..

It seems to be working for me, but I am not sure how it will work with word wrap.

Question, who do I contact to submit the change?

Cyrille

#55 SynEdit very slow on long lines

Cyrille de Brébisson — Wed, 29 Apr 2015 06:28:59 -0000

Hello Again,

I did some debugging and it seems that the issue is in the ExpandAtWideGlyphs function.

The text that I have, as stated above is, in fact, a png file (12KB) which is encoded in unicode. The encoding use is 15 bits of data per characters using characters from 0x21 to 0x8021 (simple, 15 bits of data per 16 bits on drive, does not go in any 'bad' area of unicode)... This means that the long line is a long set of weired characters :-(

I am assuming that the slow down comes from the need to calculate the width of each glyph in the string here...

It should be possible to limit the calculation to the visible size of the string, that should speed up the process significantly, but I am not sure on how to implement that...

Cyrille

SynEdit very slow on long lines

Cyrille de Brébisson — Tue, 28 Apr 2015 18:00:16 -0000

Hello,

I am editing text files with very long unicode lines (>6KB, I won't go in the details, but I am ending up with UFT16 encoded png files in editable text, test scripts...).

SynEdit seems very slow handling these lines, even with no highlighter...

Any clue what could be done to speed that up?

Thanks,
Cyrille