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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 14:12
— Overall performance is above average.

— The design does not fully comply with the guidelines.
— Box jitters when scrolling.
— Long tap is missing.
— Graphs #3 and #5 are slightly slow when filtering.
— Bonus goal is implemented, however it's not possible to tap at the pie chart and animations are slow.

— Preview glitch for the last graph:
— The left side of the slider doesn't scale the graphs (both on iOS and Android devices):
iPhone 5S, iOS 12.1; LG Nexus 5X, Android 8.1
Bold Wolf May 9, 2019 at 09:40
Thanks for your feedback.
The pie chart timeline (navigator) has broken section when pie chart is opened for a date close to the end of the chart.
When zooming the percentage chart at the beginning or at the end of the chart the pie timeline (navigator) can have less than 3 days.

Also the pie chart sectors don't separate and don't show tooltips on hover / touch / click.

Overall the work is ok and it definitely doesn't deserve so many down-votes!

P.S. I like some custom chart names - that's pretty creative.
Chrome 73
Bold Wolf May 5, 2019 at 10:15
Good job, you found bug with percentage chart!
To be honest, if I had had an ability to report myself, I would have done that. Yes, the last day in preview is broken.
About "less 3 days" - I get 3 days before and after. When it is zoomed at the beginning or at the end, there are no more days.
Thanks for your issue report! As I said, I was on the fourth place (+5 rating), but somebody decided to "dislike" me.
Great performance!
But I have problem with left range button. I can move right range, but left range button is not moving (maybe I can not touch on hint area), check it
iOS, Safari, iPhone6
Bold Wolf Apr 21, 2019 at 20:24
Sorry, I can't check it, I don't have any iOS device right now.
I think something is wrong with detecting button. I guess it is my fault. However, I have never caught this bug even on iOS device (iPhone 5).
Thanks for your issue report! I'm also glad you liked a performance of my app.
Percentage: no "100" label on Y axis
MBP 2018 15, Mojave, Chrome
Bold Wolf Apr 18, 2019 at 13:03
Yes, because labels are higher than lines :)
I know, it should be fixed. Thank you for issue reports.
Don't work on IE11
Bold Wolf Apr 18, 2019 at 04:13
You are right. 
I left ** operator in code, which is supported in ES7. It could be easy to fix by just replacing or adding polyfills, but I hadn't enough time before submission time.
Isn't it supposed to send non-minified sources? "The JavaScript code in the archive should not be obfuscated."
Bold Wolf Apr 18, 2019 at 12:56
Not minified script is also uploaded but not included in index.html.
The lines are very pixelated. Without antialiasing the app works fast.
Chrome / Ubuntu 16
Bold Wolf Apr 22, 2019 at 17:39
I know that in Firefox WebGL antialiasing is disabled. I see that you use Chrome, but I think this is the same issue. Maybe it is connected with using Ubuntu and bad configured gpu driver.

Believe me, even with antialiasing it is fast. Thanks for your issue :)
P.S.: Somebody decided to put dislikes, I had +3 and was on the fourth place. Now I have -5, this is crazy. In fact, this happens mostly in JS, the community is toxic :(
1. The lines on the minimaps are too thin. It could has been done intentionally because WebGL can't draw lines other than 1px width fast.
2. The Day/Night word in the «Switch Mode» button shrinks after changing the device orientation.
3. The «M» letters on the Y axes have strange antennas.
4. The tooltip layout is broken on a narrow screen on some positions.
iPhone SE / Safari 12.1
Bold Wolf Apr 24, 2019 at 15:43
1. WebGL can draw thick lines and main chart is drawn with polygons in my implementation. I don't think it is not fast, and, actually, I'm very sad reading "it could has been done intentionally because WebGL can't draw lines other than 1px width fast". No. Btw, my minimap is redrawed only when it is necessary, so if it had been really slow, it had been slow only when user switches checkboxes.
2. It is very strange, because I have default <span> without any styles. However, thanks for your report.
3. Yes, Canvas 2D has bad implementation in strokeText. I had no time to make it in WebGL.
4. I have seen this first time, thanks for your screenshot.
Thanks for your issue report!
The header is not adapted for mobile devices
iPhone SE / Safari 12
Bold Wolf Apr 21, 2019 at 18:01
I have seen your same issue report in other's submission, where date label was wrapped after "-" symbol. So what is your proposition? Do you want me to change the font size?
Thanks for your issue report!
The tooltip has a wrong layout (sizes, aligns, etc.). Also it trembles during a movement.
Bold Wolf Apr 21, 2019 at 17:58
I fully agree with trembling issue, it should be fixed. I had no time, sorry :(
Layout was partially "destroyed" after changing fonts to default ones: all margins disappeared.
Thanks for your issue report!
Authors, please move my app's data one dir down. Nobody can view my app since it placed not at '/entry211/' and at '/entry211/build/'
Bold Wolf Apr 19, 2019 at 13:43
Thanks for such helpful issue report!
Left/right side of chart should go outside of container if range is less when all data
MBP 2018 15, Mojave, Chrome
Bold Wolf Apr 18, 2019 at 21:26
Thanks for your comment.
You are absolutely right, I had forgotten to do that.
Preview corners not rounded
MBP 2018 15, Mojave, Chrome
Bold Wolf Apr 18, 2019 at 12:54
They aren't rounded because slider range buttons can be out of this slider to show user what exactly was selected.
Percentage: when toggle data filters it animation jumps too fast, no smooth motion
MBP 2018 15, Mojave, Chrome
Bold Wolf Apr 18, 2019 at 12:55
I agree with you, it happens when user enables bigger values, than chart has.
Really good performance on my old device! Have a like from me!
Nexus 6p
Bold Wolf Apr 20, 2019 at 14:09
Thanks! I used WebGL.
Not working in IE11, but like for the good performance and animations. Good luck in competition
Windows 8/IE11
Bold Wolf Apr 21, 2019 at 04:10
Duplicate of my first received issue. However, thanks for your issue report!. I'm glad you like my implementation.
Design mismatch
MacBook Pro 2015 / Chrome 73
Bold Wolf Apr 24, 2019 at 13:43
1) Fonts are used from default ones to not download them from Google Fonts, I was afraid, that it could not work after submission.
2) Horizontal borders: I see. It is easy to fix in CSS, however, it works on my device, I don't understand why it behaves in this way. I just should to add "border-bottom-width: 1px"
3) Size of chechboxes and map: yes, you are right, they are bigger.
No long button tap handling
Bold Wolf Apr 18, 2019 at 04:29
Chart zoom: it works with click on any area of chart (desktop) or only tooltip (mobile).
Checkboxes: Yes, you are right, there is no way to disable all checkboxes expect long tapped. I spent all my time doing zoom bonuses.
- Too little 'y' axis
- Charts must go outside of screen
- No round corners in preview area
- Values below 'zero' line (should round to lowest 'beatiful' value)
Bold Wolf Apr 18, 2019 at 19:11
1) It happens when amount of beautiful values is small
2) yes, it was in demo video, but i was confused with screenshots from stage #1, I'm sorry for not implementing it.
3) as I said, they can't be rounded, because in my implementation slider buttons can go out of range to not confuse user with what is actually selected. that is why they can't be rounded
4) if it had been rounded, than animation would not be so smooth
Bars and others: long tap should uncheck all data filters but current
MBP 2018 15, Mojave, Chrome
Bold Wolf Apr 18, 2019 at 12:52
It was already mentioned and I agree with you, I didn't have enough time.
Bars: spikes on Y go outside of max value
MBP 2018 15, Mojave, Chrome
Bold Wolf Apr 18, 2019 at 13:12
This line is not max value. It is just 120K, that didn't fit in chart's canvas.
Wrong time range when zoomed in. Because you didn't convert unix dates to GMT, but use local time instead.
Bold Wolf Apr 19, 2019 at 04:23
You are probably right, but it wasn't mentioned should I convert them for users or not. Thanks for your issue report!
Wrong zoom logic. Here is screenshot after zoom started. It looks like you display hour interval with the same width as day interval
Bold Wolf Apr 18, 2019 at 21:27
It is an animation.
[UPDATE for my prev-prev comment]:

My bad. the only issue is that thumb is placed with a shift that is equal to local timezone shift by GMT

so this is minor
Bold Wolf Apr 18, 2019 at 19:07
Yes, thanks. :)
No snapping to days, month
Pie is static
Colors of y axis texts for bar charts is not correct
Bold Wolf Apr 18, 2019 at 21:21
I don't understand what do you mean, please, be more specific. What does "No snapping to days, month" mean?
All colors were taken from JSON data, so I don't understand what is wrong. However, I haven't used guideline to change colors in night mode, maybe you meant that.
Bold Wolf Apr 19, 2019 at 04:24
Thanks for your issue report!
I am much interested, why chart is not scaled on this screenshot. Please make video how did you reproduce it.
In second chart used fixed coefficient that links lines together. It is simple, but it will not work when one line goes up and other line goes down.
Blue line must go higher on screenshot

Performance is very good
Bold Wolf Apr 20, 2019 at 14:08
There wasn't said that we should calculate that for every range. However, I agree with you, thanks for your issue report.
I'm very glad you like the performance of my implementation.
Ok, here’s the video how to reproduce wrong local y. I hope it will be helpful.
Iphone X
Bold Wolf Apr 23, 2019 at 18:12
I understood why does it happen, thanks for your video. :)
I think it is not even a bug, if there had been chart rendering at the left and right, it would had seen.
Sorry for my last confusing answer, I thought date label was wrong in your screenshot.
Thanks for issue report!
Nobody added any issues yet...