Khanda that deals with the techniques, tools, material(s), surface, perception, perspective, and three-dimensionality of human figures is Chitrasutra.

Chitrasutra is a text that deals with the art of painting and its various aspects. It provides guidelines and techniques for artists to create beautiful and realistic human figures. The word "Chitrasutra" can be translated as "the teachings of painting" or "the treatise on painting".

Importance of Chitrasutra
Chitrasutra is an important text in the field of Indian art and painting. It provides detailed instructions on various aspects of figure painting, including the techniques, tools, materials, surfaces, perception, perspective, and three-dimensionality of human figures.

Techniques
Chitrasutra explains different techniques that artists can use to create realistic and expressive human figures. It discusses the use of lines, shading, and color to depict the form and features of the human body.

Tools and Materials
The text also provides information on the tools and materials that artists should use for figure painting. It mentions specific brushes, pigments, and surfaces that are suitable for creating detailed and vibrant paintings.

Surface
Chitrasutra emphasizes the importance of selecting the right surface for painting human figures. It suggests using materials such as cloth, wood, or stone as a base for the artwork, depending on the desired effect and longevity of the painting.

Perception and Perspective
The text delves into the concept of perception and how artists can represent the human figure in a realistic manner. It discusses the use of foreshortening, proportion, and anatomical accuracy to create a sense of depth and dimension in the artwork.

Three-dimensionality
Chitrasutra teaches artists how to create three-dimensional human figures on a two-dimensional surface. It provides instructions on techniques such as shading, highlighting, and creating depth through the use of light and shadow.

Conclusion
In summary, Chitrasutra is a valuable text that provides comprehensive guidelines for artists in the creation of human figures. It covers various aspects of figure painting, including techniques, tools, materials, surface, perception, perspective, and three-dimensionality. By studying and applying the teachings of Chitrasutra, artists can enhance their skills and create visually captivating and lifelike artworks.