Problems with latest Chrome (54.0.2840.59)

[Alan Goulding]

I'm experiencing some weird things happening with lib-gwt-svg and the latest version of Chrome. It's definitely Chrome because if I go back to the previous version, the problem goes away.

The application we have draws a scrolling graph with grid lines on it. The problem is that the horizontal grid lines now get "randomly" thicker or thinner as they go up the screen. I assume this is due to some sort of anti-aliasing but I'm obviously not sure.

Has anyone seen anything like this or know how I can fix this?  I updated to the latest version (0.5.12) of lib-gwt-svg and I still get the problem.

Thanks in advance.

[Alan Goulding]

Here's an example screenshot. Previously, the horizontal lines were the same thickness across their entire width. Now you see this sort of effect where they get thicker and thinner for no good reason.

[Alan Goulding]

The lines are being drawn using OMSVGDocument.createSVGLineElement() btw.

On Tuesday, November 1, 2016 at 4:03:37 PM UTC, Alan Goulding wrote:

[Lukas Laag]

Hi Alan,
This is the first time I hear about this problem. Thanks a lot for sharing it with us. I have had several problems related to SVG with Chrome/Chromium in the past year, since their developers are in the process of upgrading their implementation to support SVG 2.0 and they tend to jettison features with little or no warning and care little about SVG 1.1 any more.

At this stage I can only ask questions and offer basic advice.

• Do you use CSS to style your lines or do you use SVG attributes ?
• Do the horizontal line span the whole width of picture or is each horizontal line made up several contiguous segments ?
• If you do not already do this, have you tried setting the stroke-width explicitly (either through CSS or through setSVGProperty call) ? Have you tried setting fill=none ?
• Do you use transforms or filters which could alter the results ?
  

Some possibly related issues:
http://stackoverflow.com/questions/7401369/why-is-svg-stroke-width-1-making-lines-transparent

If you think this is not caused by lib-gwt-svg, you should try to reproduce the issue without lib-gwt-svg if this is not too hard (by crafting an equivalent SVG by hand), so you can submit a bug report to https://bugs.chromium.org/p/chromium/issues/list

Lukas

[Alan Goulding]

Hi Lukas thanks for your reply. Embarrassingly, I've discovered this morning that the code drawing the grid lines is not using SVG at all - I somehow managed to confuse myself looking at the graphing code. It turns out that it was using Context2D.

Please feel free to delete this thread and my apologies for wasting your time.

Regards,

Alan.