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Testing and Issues

You can test this app and submit issues during the testing period of the JavaScript Chart contest.

Entries with serious issues will not be able to win the contest, but even minor issues might be important for overall results.


by rating


Fair Mammoth May 8, 2019 at 10:13
Overall poor performance.

— Slow on vertical scrolling.
— The graphs are blurry.
— The app is slow when scaling, scrolling and filtering.
— Bonus task is implemented, however, animations are slow.
LG Nexus 5X, Android 8.1
When max zoom label in header has wrong value
Slim Jaguar Apr 17, 2019 at 23:20
Last month contains only six days, so this is correct behavior.

At least I don't see any bug on the picture
Long tap raise instead of normal. Low performance on iPhone 5s
Slim Jaguar Apr 17, 2019 at 23:07
A long tap on any filter should uncheck all the other filters. This is written in task description. Check, please.

About performance. The draw for diagram is calling only once per change on scrollbar, the rest of animation is handled with css, in order to increase performance. In very abrubt cases canvas size is too low to include the next frame, so you see these pseudo lags. I could get rid of them with increasing the canvas size, but I don't want to handle the minor cases, and instead balancing within performance and animations.
redmi note 3 pro, chrome
Slim Jaguar Apr 17, 2019 at 23:09
Again. This are not lags. This seems like it is, if you quickly move scroll. But, this was done in favor of performance, so render will be called only once per move, and the rest of animation will be done by css. In order to get rid of these "lags" I have to increase canvas size. But I don't want to use more RAM just for this case
No chart preview in the scrollbar.
Samsung Galaxy S9+, Android 8.0.0, Chrome 73.0.3683.90
Not bad work at all! Not sure why it has been so much down-voted.

One small issue is that there is timeline (navigator) displayed for the single column chart in zoomed mode. And it doesn't have 100% or available time range selected.
Chrome 73
Slim Jaguar Apr 23, 2019 at 22:33
Thank you

Oh bro
How did I get to this estimation.
I have implemented all five charts with bonuses.
This is sad I would've said.
At least I can hope for this potential prize for all who has correctly implemented all the required charts
Clicks on buttons below the chart are sometimes ignored (while ring animation is still on screen)
macOS 10.14.3, Google Chrome 73.0.3683.103
Slim Jaguar Apr 17, 2019 at 11:55
There are two types of ring animations.
First one indicates a click on button, and the second is showing that global input is down. When you click two times per frame, second event for button is ignored, and click animation is not shown. Only global input circle is shown in that case, which is by design
rendering glitches on navigation viewport size change
Slim Jaguar Apr 17, 2019 at 12:24
This happens sometimes in order to increase performance. Rendering happens only once when scroll bar is changed, and then smoothing is handled with css
round border on the last chart
Slim Jaguar Apr 17, 2019 at 23:21
Yes, it is. Totally agree.
Дмитрий Apr 17, 2019 at 13:35
Telegram admins, where is my charts? I sent the archive yesterday, the bot accepted and said "Perfect! Would you like to add an URL to your app? Totally OK if not."

I do not see it in the list, what's the problem ??
Poor quality graphs when zoomed in
Slim Jaguar Apr 17, 2019 at 23:11
1:1 css to html size preserved on phones
Super fun animation "Supupleks" :) Cool!
Labels on y-axis disappeared.
Slim Jaguar Apr 19, 2019 at 10:26
I observed this bug after switching tabs during animations.
How did you get it?
Wrong data on pie chart - there is no day with 75k apples. Also information tooltip should show exact value, not round it.
Slim Jaguar Apr 19, 2019 at 10:46
Good point!
Although percents are correct.
Thanks for your feedback
All the charts are very blurry
Chrome 73 / Arch Linux
Slim Jaguar Apr 23, 2019 at 22:38
Not very, but after all, yes they are. I bet all on performance and size
Forgot the screenshot. Here is it
Slim Jaguar Apr 19, 2019 at 13:41
1:1 css to html size preserved on phones
Sometimes a mouse click performs text selection. And then entire text of the page become selected. As you like suggesting - i found yours bug, then you finding on mine page.
Slim Jaguar Apr 23, 2019 at 22:36
Don't see any issue. It's even hard to select text
Another issue is with the pie chart:
When you zoom in first date plus 2 or last date minus 2 the pie chart jumps to the wrong date.
In case of the last date - it is impossible to open a pie chart for it at all :(
And the values (both percentage and numbers) are not the same in the graph and in the pie chart, but that has been partially reported before.
Chrome 73
Slim Jaguar Apr 20, 2019 at 18:45
The date on diagram shows what is on the right side from it. So when you choose the last one, this data is not presented in the contest.js.
For the first issue, I agree, frame is always on the center of week. This wasn't by design, but I haven't enough time to implement all the stuffs
I could reproduce the reported bug with horizontal lines (a.k.a. y-axis labels) - but that happens only for line chart and stacked bar chart. And when you continue resizing it seems to self-fix. But it can break again later. Not sure what causes it, and I don't see it as a huge problem - it doesn't break any core functionality.
Chrome 73
Slim Jaguar Apr 20, 2019 at 18:49
I know, there is the bug. But I can't reproduce it that way.
Thanks for your feedback anyway
The application loads 1MB of data to show the first frame. It take much time.
MacBook Pro 2015 / Safari 12.1
Slim Jaguar Apr 24, 2019 at 23:11
But full app weighs 975 KB
which is 2-3 times less than almost any other app.
Beside the source is not minified
Nobody added any issues yet...