Certainly perspective itself contributes to happiness. When we are confronted with someone else's tragedy we are often grateful for what we have in comparison. Or when we ourselves come through a crisis, even the worse for wear, we can be happy in our current improved state.
Happiness is a choice. Yes, even for those who were born genetically grumpy, it's possible to choose to be happier. Even when things around you are falling apart, it's possible to choose to be happy. I learned that by the time I was 3 -- a lesson learned from my parents.