The most important way of establishing the picture plane is by means of texture. It makes the surface felt as a uniform, tangible material. It is irrelevant whether this texture is achieved by means of drawing or painting, or arises from the substance of the picture's surface itself. Smooth white paper has no texture, nor has a smooth, polished, shiny painting surface, or smooth fresco plaster, whereas coarse paper, rough canvas and plaster have, If a textured material is available there is no need to trouble with graphic means of creating texture. On smooth surfaces, however, texture has to be created with appropriate pencil or brush strokes, Even the simple expedient of interrupting the line indicates that it is not intended to cut up the surface of the picture, but rather to work over it as though stitching a thread into the basic material of the picture.
Van Gogh in the course of his development as a painter, achieved the most uniform strokes possible for textural effect. With him it was certainly not a device, not an external matter. His pencil and brush strokes wind like eyeless serpents over the whole picture, an expression of the dreadful unseeing battle of all living things against each other. The texture gives exceptional emphasis to the surface, an impression which is again heightened by "false" perspective and a flattening of solid forms.
Flattening of solids and distances can also be used to transform all things depicted into a scheme of geometric figures. There is something of this in almost every sketch in which the artist has begun by linking up lines and shapes, seeking the way one curve or rhythm leads to another. This net of fine lines builds up into the effect of an expanding cobweb.
A uniform texture creates the quietest effect. But it can be carried too far, appearing mannered and so insistent that the subject of the picture becomes of secondary importance. A consistent texture is most effective on a rough surface. The original support may possess this, or it can be obtained with a thick application of paint from brush or palette knife. The rough surface gives shadow effects, like a fine network of lines spread over all parts of the painted or shaded surface. A rough surface can also give a broken texture to a light, rapid brush stroke so that the basic color shines through everywhere, again emphasizing the picture plane.
Wherever a material creates a strong effect of texture or color by its substance, such as knotted carpet, tapestry, or varnished wood, it will give a strong suggestion of plane. Even the most brightly colored mosaic is absolutely flat in effect. Old book illustrations where the colors are outlined in black have the same flat look as stained glass with its black lead outlines.
In all these different techniques, mosaic, colored drawing with black contours, and stained glass, the coarse net of irregular lines, which is both technically necessary and which determines the form, creates an effect of flatness.
If you look through a coarse-meshed net or curtain, its texture will hold the space behind it in its own plane, as long as you take care to look at both net and background together. If you look only at the distance, the net becomes blurred, and if you focus upon the net, you see it against a blurred background. This experiment can be repeated in front of a picture painted on coarse canvas; it shows how a picture can at the same time give an effect of flat surface and of living depth.