Hatching

A hatch pattern ( sgraffiare of Italian, " scratch ", compare sgraffito ) is the totality of many fine, straight, parallel lines which are prominent in an area drawings, plans, maps or illustrations.

Use

Hatching is used:

• For adding terms to the specific areas
• The representation of inclination to the plane
• The appearance of the shadow and lighting

Overall hatching always used to make a graph more readable, and / or to have them plastic (spatial ) appear. Of special importance is the hatching for black and white images, while always easier availability of colored representations of the hatching more and more displaced (eg printing).

Hatching in technical drawings

Hatchings used in technical drawings, to identify sectional areas. In this case, these areas are filled with thin parallel lines equally spaced at an angle of 45 ° to the main axis of symmetry of the component shown. ( The sloping lines are supposed to symbolize a saw cut. ) If there are multiple parts in a cross-sectional view, the hatching is also used the parts visually distinguish from each other. The hatches then differ in the direction of the lines ( ± 45 °) and their spacing.

Furthermore, there is according to DIN 201, which was replaced by DIN ISO 128-50 in 2002, yet a variety of hatch material-specific. Usually indeed the Grundschraffur is only used, however, it can sometimes be useful, including the drawings to refer to a special material. Thus, for example, the use of rubber gaskets often the cross-hatching for plastics in use. Parts with small cross- sectional area ( eg thin washers) must be for the sake of simplicity usually quite blackened.

Hatching and hatched lines in cartography

Hatching is used in cartography to represent thematic maps on areas with specific geographical features ( for example, geological features, language areas, historical developments ). The hatch for an analog of area of technical drawing is applied.

Earlier hachures were often used for the representation of the relief around the site represent plastically. The hatched lines run eg in the fall line. Today, cards are, however, due to the more accurate interpretability, contour lines and / or hillshading common.

Map depicting a hill by hachures

Hatching in the visual arts

In the artistic drawing and illustration, the technique of hatching is used to represent gray values ​​, hues and shades close to each other by means of set lines. In addition to simple parallel hatching, the technique of cross-hatching is also frequently used: About a first layer of parallel lines, a second layer is drawn in such a way that curves intersect at an angle. This can be very good hatching subsequently make darker and also represent light-dark gradient. One of the first who used the cross-hatching in the engraving, was living in 1450 engraver Master ES.

Heraldry

In heraldry heraldic hatchings are composed of dots and dashes to represent heraldic tinctures in black-and- white images of coats of arms as part of the tincture.

Aid

To produce uniform hatching serves Schraffierlineal, which consists in the main, of a parallel ruler, which is displaced by pressure of the finger on a little button after each line to a very specific, but previously adjustable size so that the lines which we then use the drawing pen draws, get exactly the same distance from each other.