The characters in your question (k
, f
, a
, and e
) are all of the usual suspects when it comes to italicizing a roman typeface. While not all fonts conform to these modifications in their italicized incarnation, these are in fact very traditional transformations and do indeed have precedent. Here are some examples of the various transformations a roman typeface might undergo in a traditional conversion to italic:
A "round" or one-storey a
An e
whose bowl is curved rather than pointed
An f
with a tail (known as a descender)
A k
with a looped bowl, a k
with a ball terminal
A p
with an intersection at the stem (ascender)
A v
and w
with swashes and curved bottoms
A z
with the stress on the horizontal strokes as opposed to the diagonal vertical one
It's important to note that none of these are required to design the italic version of a typeface. As you can see from the previous examples, Consolas does not employ all of the tradition italic character styling but it does has a couple of other classic modifications that are worth mentioning:
- Double-loop
g
replaced by single-loop version.
- Bracketed serifs replaced with hooked serifs (
i
, j
, and l
)
Some examples of classic italic modifications:
Garamond
Bodoni
Perpetua
Source: Italic Type - Wikipedia