Renaissance artists were inspired by the so-called Franciscan radicalism to switch their focus to the natural environment. It was Saint Francis of Assisi who extolled the beauty of the world and encouraged people to enjoy but also protect nature. Another issue that Mary D. Garrard, Professor Emerita of Art History at American University in Washington, mentions is the depiction of nature as mother, bride or mistress. Nature's images derive from the gender roles in the social world and express the idea that art and culture are masculine spheres, which depend on feminizing everything else.
Whether it was real people or imaginative figures, such as Nature as described above, Renaissance artists paid much attention to the accurate depiction of the human body. The trend was evident since the early works of Italian Renaissance pioneer Giotto di Bondone, but it was Leonardo da Vinci's works that brought a revolution. His formal training in anatomy allowed him to use the human body as a means of emotional expression.
The term perspective refers to the representation on a flat surface of what the human eye can see. In other words, it's the depiction of the world in three dimensions. In his work "Renaissance and Reformation," professor William Gilbert stresses the influence of science in artistic creations of the period and especially the discovery of a mathematical method of attaining a three-dimensional impression, first attributed to architect Filippo Brunelleschi around 1420.
In a bid to enhance depth and three-dimensionality, Renaissance artists used not only the linear perspective technique, but also the so-called sfumato and chiaroscuro. The former term refers to the use of lightening dark parts and brightening dark spots of a painting. A prominent example of sfumato usage is Leonardo da Vinci's famous "Mona Lisa" painting. Chiaroscuro is the strong contrast between light and dark to give the illusion of volume, primarily on human figures. High Renaissance painter Raphael was a notable user of this technique.