For complex styles - with a complex graph - it may often be helpful to zoom in some filters and see what the intermediate result is. Style Editor allows you to zoom in and out the whole graph or in only one filter by simply scrolling with the mouse.
_____How to zoom in and out the whole graph
In the Style Editor simply scroll up and down the mouse wheel. Filters will be all resized together to the same size. Click the autoarrange button (in the lower icon menu bar) to get the automatic arrangement of the filters.
Note: There is a minimum and a maximum view size for the filters.
The minimum view: filters are really small and you can not really read or see their name and thumbnails.
The maximum view is not really useful when there are many filters, as the graph becomes messy.
It is preferred to use the medium view (used by default).
_____How to zoom in only one filter
Select the filter and scroll up with the mouse while keeping the Ctrl button pressed. To zoom out scroll down.
You can also zoom in 2 or more filters at a same time. Select the filters by keeping the Ctrl button pressed while selecting and scroll up. Scroll down to zoom out. You may zoom in a filter and then decide to zoom in another one too: in this case the 2 filters will be probably different sizes, but will be zoomed together if both are selected.