Understand Anomalies of Leaflet Interations

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paradiselost
Posts: 92
Joined: Sun Apr 06, 2014 10:22 am
Location: Philippines

Understand Anomalies of Leaflet Interations

Post by paradiselost » Mon Jun 25, 2018 12:31 am

Labeling differences include how receiver names are handled between original 2.4.1 and V3.

The original 2.4.1 Leaflet display looked at the receiver names length and if they were more than 10 characters or spaces or digits the font size was reduced to fit on the label line displayed. Different parts of the map displayed this characteristic.

On the V3 Leaflet Version labels are handled differently. FA-DGT ADSB for example in the 2.4.1 version was font resized on portions of the map so all 11 characters, spaces or digits were displayed in the size font necessary to get all 11 characters on a label line. V3 changes the behavior from Font resizing to a fixed line length.

On V3 leaflet, FA-DGT ADSB which is 11 characters drops the vertical part of the F and the trailing part of the B but without resizing the font. Receiver names of 10 characters, spaces or numbers display correctly the same size as the other label lines.

The length of your receiver names is key, 10 or less is ok, 11 or more leds to unintended consequences.

paradiselost

agw
Posts: 2146
Joined: Fri Feb 17, 2012 3:20 am

Re: Understand Anomalies of Leaflet Interations

Post by agw » Mon Jun 25, 2018 1:55 am

I think you're comparing SVG marker text against rendered marker text.

VRS has never counted characters when determining font sizes. If it's rendering text on to the marker then the code starts with an ideal font size for the marker text and if the text doesn't fit at that font size then it tries progressively smaller and smaller fonts until it either finds one that fits or it hits the minimum font size. VRS renders text onto the markers if you're not using Mono and you have SVG graphics switched off (version 3 introduces SVG marker support, previous to that it always rendered text onto the markers).

SVG graphics are rendered on the browser and - as far as I'm aware - there is no support for that kind of adaptive font sizing. You just pick a font size and go with it. If you have long labels then they can be truncated. The point at which it truncates will depend on the width of the marker, they're not all the same size.

If you're hitting this issue then you can disable SVG graphics in Tools | Options | Web Site to go back to using rendered marker text.

paradiselost
Posts: 92
Joined: Sun Apr 06, 2014 10:22 am
Location: Philippines

Re: Understand Anomalies of Leaflet Interations

Post by paradiselost » Mon Jun 25, 2018 3:51 am

V3 works out of the box with labels of the proper length as noted without the SVG configuration confusion in 2.41 upgrading from previous stable versions.

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