I really don't think Chopin ever wrote any decidedly "happy" pieces, with few possible exceptions (for instance, maybe the rondo at the end of the E minor piano concerto, which seems pretty boundless); indeed, to me, he seems to usually transcend typical happiness and, instead of approaching ecstasy as Scriabin is often said to have done, transforms the emotion into something richer and far more complex. To me, it is more like a morbid trepidation which is greeted dutifully with a mask of hope or happiness. Take the Grande Polonaise Brillante. On the surface, it seems full of felicitous energy that may appear to be unchecked joy, but notice how its melody is composed of several descending lines which, over time, are made increasingly more complicated by rhythmic variations. It isn't happy, I think, not fully so at least, but instead is a sort of way of reminding us that although we're still alive and can BE happy, we still are all facing death and, as is popularly maintained, Chopin dwelled perhaps a little too much on that subject, knowing that he would die a premature death.
I think the Barcarolle is a great example of that kind of thing.
Topic: What do u think about barcarolle chopin?