B4J Question GoogleMaps - Polyline Banding Problem [Issue Identified But Not Solved]

[RichardN]

This Program used to work perfectly....!

It simply depicts a number of Geodesic Polylines from London to other major world cities. Now the polylines appear starting and ending in the wrong places and intermittently blank along their length. I originally thought it might be a graphic card problem but all drivers and B4J libraries are up to date. This one has me puzzled.... has something been updated that I have missed? Any suggestions?

 

[Erel]

Have you changed the Java version?

It might be related to a change in Google JavaScript behavior.

 

[klaus]

What is the Wondows setting of text size ?
More than 100% ?
The GoogleMapsDemo program works correctly with 100%.
But, with higher settings there are problems, polygons are not drawn correctly.

 

[RichardN]

Thanks @klaus that appears to be the problem. With identical JDK and JRE versions two compilations perform differently on two PCs. On my desktop with a native 1920x1080 screen and text size set at 100% the program performs as expected. On my laptop with a native 1920x1080 screen with the text size set at the (recommended) 125% the problem appears.

I presume this a jGoogleMaps library issue where screen scaling is not accommodated ???

 

[Erel]

I presume this a jGoogleMaps library issue where screen scaling is not accommodated ???

Drawing happens on a lower level. The problem is probably in the WebView engine itself.

 

[RichardN]

Just an update to my previous observation. Being an amatuer videographer who switched from HD to 4K a while ago I recently splashed out on a native 4k monitor (3840x2160 px). Whilst the image quality is stunning you have to change the default look of several Windows applications as the desktop icons and in-app buttons become so small as to be unusable.

With the new monitor Windows defaults to 175% scaling which is OK but the symptoms detailed in the post above become evident again. However switching to 200% scaling provides a perfect picture with the highest quality.

 

[klaus]

It works OK with Java 19.

 

[RichardN]

Java 19 also working here on a 4k native screen at 3840x2160. Fonts/Icons set at 200%