shadings

Shadings refers to the gradation of lightness and darkness, or color, used to convey depth, form, texture, or mood in images and scenes. The term can refer to the act of shading as well as to the results produced by it. In visual arts and related fields, shading describes how artists model light on surfaces.

In manual drawing and painting, common shading techniques include hatching, cross-hatching, stippling, and blending. Hatching uses parallel lines; cross-hatching uses intersecting lines; stippling uses dots; blending softens transitions. Artists adjust line weight, spacing, and pressure to suggest a light source and three-dimensional form.

In computer graphics, shading models simulate light interaction with surfaces. Flat shading assigns one color per polygon; Gouraud shading interpolates vertex colors for smooth transitions; Phong and Blinn-Phong shading interpolate lighting to produce smoother highlights. Modern rendering often relies on physically based shading, which uses material properties such as albedo, metalness, roughness, and light transport equations to achieve realistic results.

In cartography and 3D visualization, hill shading or shaded relief applies a simulated light direction to terrain to emphasize relief and improve readability. This technique, often combined with color ramps, helps convey elevation and texture in maps and models.

The term shadings can also appear in everyday language to refer to window coverings that control light, such as shades or blinds, though this usage is distinct from artistic or graphical shading.