Those are Shanghai Rice Cakes - Nian Gao If you google, you'll find a bunch of recipes for what I think of as the "standard" rice cake dish, with shredded pork and cabbage. In most of them, the soaked/softened rice cakes are added at the end, after all the other ingredients, so they only get lightly fried.
Risotto is a common dish down my parts of the woods, being so close to Italy and all. Making your fist few risottos might seem a tad overwhelming with all the tiny details and tricks that recipes will hit you with, but you'll soon get a hang of it and think nothing of it. One 'seasoned advice' though - to keep it fairly moist and remove from the heat while it's still bubbling on top with its own juices. It's OK to keep it even slightly waterish, as that adds to its creaminess (most of the times I've eaten it in Italy, they actually leave it nearly thick soup like). Then keep it covered but off the stew for ~ 5 minutes, while you chop some fresh herbs of choice and grate Parmigiano cheese.
OK, since this is not a recipe question, let's continue answering your 'perfect translucent' question; I'm not sure which recipe you're referring to. but e.g. this one mentions:
Stir in the rice and sauté it too until it becomes translucent (this
will take 7-10 minutes), stirring constantly to keep it from sticking.
It also gives advice what rice to look for and is most recommended for risottos. I tend to agree about the article's choice, but you shouldn't have difficulties finding rice that is marked to be suitable for cooking risottos. These tend to be rounder, but most importantly (and what the article I link to fails to mention) they'll have any excess starch removed from it, to allow for longer cooking without overboiling it.
This excess starch removal also helps with its ability to soak in oils (extra-virgin olive oil is recommended, preferably cold pressed, and some butter if you like creaminess of your risottos or to soften vegetables faster), making it nearly translucent in the process, similar to how normal white paper becomes nearly translucent when soaked in oil. This rice will later become white-ish again as you add water and it starts releasing more starch, gathering on its surface.
That 'perfect translucent rice' in your recipe probably refers to the rice being perfectly (equally?) soaked in oils and butter, rather than trying to suggest it should be perfectly translucent in a way that you could see through it. The latter, I'm afraid, isn't possible with any rice I've seen sold neither here, nor in Italy (or in UK, for the matter). The only way to literally achieve 'perfect translucent rice' that I can think of is by using rice-shaped Chinese pasta (I don't know what it's called, but we nicknamed it in my family 'fake rice', that we sometimes use to trick kids into eating 'rice' dishes that they otherwise wouldn't touch) that is actually pasta made of rice starch instead of wheat flour. This rice-based pasta will be literally invisible to the eye when boiling in pure water. But don't use that for risotto (it tends to overcook fairly quickly), unless you have really picky kids that wouldn't touch it otherwise!
Hope this answers your question, and I've attached a photo that approximately shows how the rice should look like when it's supposed to become 'transparent' and equally soaked in oils and butter.
EDIT: For the better of me, I honestly can't find the name of that 'rice starch pasta shaped like rice', but I presume it has a Chinese name, and since I don't speak Chinese, I won't be able to find it. It is however available in some better stores throughout Europe, and quite similar to Orzo, only that it obviously isn't made out of Semolina (durham wheat flour) but rice starch, making it perfectly translucent while boiling and nearly translucent afterwards, much like thin rice noodles.
Best Answer
As I understand it, it's down to the flavour you get from frying the rice. However, it does also break down some of the starch which reduces the thickening it can do when the risotto cooks, which might cause a problem. I can attest to the flavour, but I've not done experiments about thickening.
Serious Eats had a good article on the topic though, in which such experiments were described. The solution in that was to wash the rice in the stock, then fry the rice, then add the stock containing all that undamaged free rice starch during cooking, thus giving you toasty flavour and creamy risotto with no questions asked. I haven't tried that, but it seems like a fairly sound idea to me.
http://www.seriouseats.com/2011/10/the-food-lab-the-science-of-risotto.html