Correct. Furthermore, you have to consider that it is applied based on whatever the currently active font asset and point size is. So if you are using the tag or tags, these will be affecting what the results are.
For example, if the raw text is “Hello <size=2em>World”, then assuming the initial point size was 36, the word “World” would end up at 72 point size.
If the line height is set at the start of a block of text, it should remain consistent and unaffected by changing fonts or even point size.
You can see in the example below that the line height (second line) is affect by the font change on the word “simple”. By default line height is from lowest descender of previous line + line gap to the highest Ascender of subsequent line.
Now in this next example, you can see how the line height is unaffected by the font and size change and based on the font and size at the time it was applied.
So based on how you were doing it per blocks, should work. I will check as the application of this block of tags whether inline in the text or coming from a style should be the same.
Again, you have a choice of using (px) pixel units, (em) font units, or (%) percentage.
Unfortunately, not all fonts are created equal and since scaling / size of characters, line height, etc. is all up to whoever designed the source font file, you most of the time end up with fonts of the same point size having very different metrics. The worst I have seen was 2X relative to each other with a by shift in the baseline position.
Fortunately, in the font asset inspector, you can actually change the relative scaling of a font asset, ascender, descender, baseline and line height to essentially normalize this font asset so they blend in better with each other.
