Piero Della Francesca was an Italian painter from the 15th century Renaissance period known for his use of geometry and perspective in paintings. He contributed frescoes that explored these techniques. Della Francesca was influenced by early Renaissance artists in Florence and worked with Domenico Veneziano. In his later years, he wrote a treatise on perspective in painting. Oskar Schlemmer was a 20th century German artist, designer and choreographer associated with the Bauhaus school. He incorporated geometric shapes into figurative paintings and sculptures and was influenced by his work choreographing dances. Schlemmer believed art should not strive for perfection but maintain a natural quality.