@JonB thanks for googling :) . I have seen some more example. In case of GraphicsView fill transparent on scene did not help. I am pretty sure there is some way to do it, need to google more

Hi,
If anyone here has any experience or knowledge related to this issue, I would be extremely grateful for your input.
Even a small suggestion or a nudge in the right direction could make a significant difference for me.

We're using 5.15.2. Had same problems with 5.12.3.

@sachinrd
You are welcome.
Do notice this way of printing it only works when it
can fit on one page. if it has many rows, it will not be optimal :)

I found out that I can reproduce this behavior by setting QT_DISTANCEFIELD_DEFAULT_BASEFONTSIZE, QT_DISTANCEFIELD_DEFAULT_SCALE and QT_DISTANCEFIELD_DEFAULT_RADIUS variables. With these, the problem occurs even on Windows.

Not sure whether it's the same problem or not, but if QT_DISTANCEFIELD_DEFAULT_RADIUS is NOT DIVISIBLE by QT_DISTANCEFIELD_DEFAULT_SCALE, the problem occurs 100% of time (some letters will disappear).

Example:
export QT_DISTANCEFIELD_DEFAULT_BASEFONTSIZE=128
export QT_DISTANCEFIELD_DEFAULT_SCALE=12
export QT_DISTANCEFIELD_DEFAULT_RADIUS=96 // If I set this to 95 or 97 or anything not divisible by 12, it will break.

Can someone explain me what these distancefield environment variables do and whether this is an intended behavior?

@fcarney said in Poor quality colored emojis, how to fix that?:

font.hintingPreference: Font.PreferNoHinting

Wow excellent! This resolved my issue. Thank you very much

I see, thanks for the response.

I stumbled today on an old thread where user wanted the same font rendering as in Photoshop. One of person responding said that they made their own wrapper of FreeType. I guess I will try to render icons using that and see where it goes.

Not gonna mark it as solved for now though, maybe someone will stumble on it with some experience.

Hi
Seems already reported
https://bugreports.qt.io/browse/QTBUG-70387

@SGaist
Thank you so much! Your response was much helpful!

I have found a solution that kind of does the job, although takes three times as much memory.
Every update I calculate the difference between the new and the old saturation matrix, this eliminates 60% of the nonzero values, which means it gets drawn that much faster.

As a second layer of optimization I call repaint with a rectangle describing the most important zone, and call update every 60ms.

Yes, I did see that example, however how to run it? it builds a library (how do I connect that to a normal app?)
And is that the best way to build an app that heavily relies on the drawn graphics?

Just realized, that I had still thread still open.

I'll share how I managed to circumvent the problem. Sadly I haven't found a real solution as of now.

In the function that makes the screenshot, I added this line just before calling QWidget::render

this->setStyleSheet("cStackedWidget {background-color:white;}" "QWidget#LiveStatus{background-color:white;}" ... //List of all QStackedwidget Pages ... "QWidget#FanThreshhold{background-color:white;}");

For some reason I have to set the stylesheet new for each time. Simply setting this once will not work.

Anyway, I'll mark it as solved,
unless someone else has a new idea !?

@m.sue

Great find for the properties, and if I cannot find a way to tweak the rendering settings for draw distance then I guess that would be my best way to do it.

Thanks.

Hi Clockwork

I didnt read your code with much attention, but for starters if all you want is draw a triangle, check this tutorials I did https://bitbucket.org/joaodeusmorgado/opengltutorials
I'm using vbos, to draw triangles. I'm using all OpenGL native calls, but should be pretty easy to convert to Qt OpenGL functions. I also recommend you this book wich is great, it has a lot of details that usually are ommited in other books http://alfonse.bitbucket.org/oldtut/index.html