Ticker - incorrect duration with number of items set

[PeterMis]

Scenario

Add a new RSS ticker with an example feed like https://ceu.xibo.cloud/mediarss/feed.xml
leave the default duration to 10s and 'duration is per item' enabled.

If we schedule this to the players we will see each item for 10s, for total duration of the layout 40s in this example (there are 4 items in the feed).

Edit ticker and change number of items to 4, which technically should not change anything, as we still want it to show all items that are in this particular feed and we would expect each item to still be on the screen for 10s since we want 4 items, total duration should remain at 40s for this layout.

That's not what will happen, with the number of items set to 4, each item will be on the screen for 40s for total layout duration of 160s.

If we will leave duration at 10s and change the number of items to 2, each item will stay on the screen for 20s, for 40s total duration.

In short there is a math problem with calculating duration when the number of items is set, it will have impact on all widgets that use this setting.

The .htm files in Windows player (in simplified version to not paste everything here)

With numItems empty (default)

var options =
{"type":"ticker","fx":"fade","duration":"10","durationIsPerItem":true,"numItems":0,"takeItemsFrom":"start","itemsPerPage":1,"randomiseItems":0,"speed":"2","originalWidth":"1920.0000","originalHeight":"1080.0000","previewWidth":0,"previewHeight":0,"scaleOverride":0};   
<!-- NUMITEMS=4 -->
<!-- DURATION=40 -->

With numItems set to 4

var options = {"type":"ticker","fx":"fade","duration":"40","durationIsPerItem":true,"numItems":4,"takeItemsFrom":"start","itemsPerPage":1,"randomiseItems":0,"speed":"2","originalWidth":"1920.0000","originalHeight":"1080.0000","previewWidth":0,"previewHeight":0,"scaleOverride":0}; 
<!-- NUMITEMS=4 -->
<!-- DURATION=160 -->

OP - https://community.xibo.org.uk/t/problem-with-ticker-module/12630