Even though you might not think of Graffiti art as "math," many Graffiti artists do make use of it. For example, when you see a shadow effect used, the artist is dealing with different angles to give it that look. Also, keeping objects (such as a building) in correct proportion ensures that when you look at the art, you will be able to indentify what exactly you are looking at. Perspective can also be used as in the image below.

Author: Saber, Photo: Birch
Please visit the acknowledgements page to see more of this artist's work at the site that hosts it.