I'm making a grid of hexagons by placing Positioned Widgets. I have them inside an Interactive Viewer Widget so I can zoom in and out and move around.
Issue I'm having however is that with a large number of them being rendered it's far too laggy. It's unusable with about 4000 rendered on screen and ideally I need 10s of thousands. And this has nothing to do with the Widget itself as it's the same when replaced with a SizedBox with a Container or Text in.
I am using an InteractiveViewer.builder and only render the Widgets on the screen, which works great and there's no lag when zoomed in with few widgets on the screen, however I need to zoom out and see more.
I've also run in release mode and it's the same. I'm running in Windows and my PC is more than capable, too capable compared to the phones this should also be able to run on.
Is there some way to increase performance, or some other way I should be doing this instead of thousands of Positioned Widgets? Or is Flutter just not suited for this?
Edit: Image.
Using a widget for each individual hexagon at that scale feels like massive overkill. If you're going to use flutter, maybe use a CustomPaint widget, which allows you to draw shapes directly to a pixel grid?
You could wrap it in a GestureDector and implement scrolling and zooming via that perhaps?
I'm looking for trajectory animation just like how https://leo9studio.com/ has done. You see while scrolling, those balls get scrolled from top to bottom. How can we replicate exactly in Flutter Web?
Additionally, how to create such a smooth scrolling effect in Flutter?
rive.app would be a good place to start looking, since you aren't really providing any context or code other than just a random idea, they have a great community and I have used their packaged for some neat animation on my web apps. They have a way to create your own designs and animations which would probably be the case there, unless you wanted to make it all with code then that would be a different story.
Or look at this post here How to animate a path in flutter?
Let's say you have some flutter widget, for example, a TabBar. It is rendered in a rectangular box. I need it to be rendered in an arc so that the text and the underline follow part of a circle (or better still, a bezier curve).
How can that be achieved?
This illustrates what I am trying to achieve - bent TabBar widget:
Please note that in this case, the TabBar bends following and an arc (edge of a circle). This is what I need immediately. However, in the future, I might need bending that follows the edge of an eclipse so a solution that allows it would be preferable.
Also, a solution that works for different widgets is preferred.
IMPORTANT: I do NOT want to clip a curved shape of the widget. The entire area of the widget should stay visible. Instead, I need to bend the content of the widget (=bend its render image).
Apologies for the bold font but without it, people will keep posting answers about how to clip a widget which is trivial in comparison and useless for my problem.
An answer "this is currently not supported by Flutter" from authority (e.g. high reputation in Flutter tag or Flutter a team member) will also be accepted.
One approach: Use a CustomPaint to draw lines/areas/etc freely
You can use a CustomPaint to draw whatever curved lines, areas, etc freely. Therefore, you can definitely achieve your goal - since they are nothing but curved lines, areas with curved edges, rotated texts, etc.
That will take a bit of work, but if you encapsulate it well enough, it is not that hard to implement. For example, draw a Path with filled red area, then draw a white arc, then draw several texts with calculated rotations, etc. Sounds like you can do that within maybe hundreds of lines. If you find difficulty implementing this please comment and I will explain.
Another approach: Hack Canvas such that the call to drawLine becomes indeed calls to drawPath, etc.
You may do the following to allow bend/crook for any widget (and their combination, of course), but this may need a bit of engineering. You can make your own Canvas, say, class BendCanvas implements Canvas {}. The BendCanvas.drawLine, for example, has an implementation of Canvas.drawPath with a curved path cooresponding to the input "line". Similar things hold for drawing rectangles, etc. Then you need to hack Flutter's painting logic, such that it takes in your own BendCanvas instead of the original canvas. This is a universal solution, and it is much more efficient (less code) if you plan to have a lot of bend UI; but if only on bend TabBar, maybe use the first approach.
As for the bend text
In the two approaches above, we have mainly described how you draw the bended rectangle (i.e. draw an arbitrary shaped widget). As for bending text, see: https://github.com/flutter/flutter/issues/16477 , which is still an open issue.
Remarks
It is not possible using transformations. As explained in the comments, you already see Transform does not work - it is affine or perspective, which, by definition, will not bend. Then what about other transforms? After some research there seems to be none. Then, what about looking under the scene. We know Flutter uses Skia under it to draw the UI with high performance, then let us search through Skia. However, it does not provide any transformations like bending. So there seems no use.
P.S. I am not that high reputation in Flutter tag, but I did answer >100 Flutter questions (including some dig-into-source-code style ones), and have developed >100k lines of Flutter code in the production app.
I'm trying to recreate a UI in flutter that looks like this I need to get this shapes in the position they appear in the image above, I did some research and came across Flutter Custom Paint, tried checking for tutorials on how to use it to achieve this design but can't find anything that points me in the right direction. Please is there anyway in flutter to recreate this UI?
Instead of complicating things
You can use stack for overlapping
And for that circles you can use containers with borderradius
and using positioned widget to position the circles based on your need
MORE THAN THIS
you can export that design as an image and use
Stack{
children[
THAT IMAGE,
YOUR UI,
]}
I'm generating multiple widgets(Containers in this case) using a ListView.builder and I also use a custom ClipPath to give a custom shape to them.
I was wondering if would it be possible to translate or somehow overlay those list items in order to place them so that the background(black area in the attached screenshot) would be covered. By that I mean I want to place them right under each other, like puzzle pieces. To be able to fit them right under each other would probably mean they would have to be overlayed somehow. Was googling but without any success.
Hopefully there's some Flutter experts out there who are nice enough to guide me. Thanks a lot!