SUTFACES: Spatial and plane curves as directices or generatrices in surfaces' generation. Characteristic views and direct detection of the geometric structure of the surface. Developable and nondevelopable surface; ruled (quadrics, conoids, cylindroids etc..), Helical, convolute; arches, vaults and domes, roofs. Axonometric views. The concepts of visibility and visual realism. SHADING AND VISUAL REALISM. Basic principles of shading. Illumination dividing line. Detection of characteristic elements of shadows in orthogonal and oblique views and axonometric images for parallel and central illumination rays. VISUALIZATION AND GEOMETRIC STRUCTURE OF COMPLEX 3D FORMS IN PI. Three point perspective. Rotation and fictive the true sizes. The concepts of visibility. Application to plane figures, polyhedra, solids of revolution, plane sections and mutual intersections of surfaces, etc.. Visual angle and choice of PI.Two point and central PIs. Analysis of complex surfaces: ruled surfaces, arches, vaults, domes, roofs and the like. VISUAL REALISM IN PI. SHADOWS. REFLECTIONS. Central and parallel ilumination rays. The characteristic elements of light rays for the sake of direct determination of shadows in PI. The reflections in horizontal, vertical and oblique mirrors. RESTITUTION OF PI. Criteria for the analysis of PI metric properties and the detection of spatial relations of objects displayed in PI. ILLUSION OF SPACE AND APPLICATION TO THE THEATRE PERSPECTIVE.