Labeling (map design)

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Cartographic labeling is a form of typography and strongly deals with form, style, weight and size of type on a map. Essentially, labeling denotes the correct way to label features (points, arcs, or polygons).

Contents 1 Form 1.1 Italics 1.2 Case 1.3 Color 1.4 Spacing 1.5 Kerning 1.6 Font vs. Typeface 1.7 x-Height 2 Style 2.1 Serifs 2.2 Sans serifs 3 Weight 4 Size 4.1 Effects of Size 5 Legibility and Perceptibility 6 Placement 7 Guidelines for Labeling Point Features 8 Guidelines for Labeling Line Features 9 Guidelines for Labeling Area(Polygon) Features 10 See also 11 References 12 Notes

[edit] Form

In type, form describes anything from lengths between letters to the case and color of the font. Form works well for both nominal (qualitative) and ordered (quantitative) data.

[edit] Italics

Italics describe the sloping of letters setting it apart from non-italicized words (or vice versa). Using italics on a map also slightly decreases the size of the font as it shapely squeezes it around features. When introduced, the idea was to condense the text by italicizing it, thus creating more text on the pages. The slope in the font was created to mimic the flow of cursive handwriting and thus, the angles of italic letters range anywhere from 11 to 30 degree and consequently, serifs are absent.

As a general rule on maps, the smaller the point size of a font, the more condensed and difficult it becomes to read. In an example of labeling a globe, ocean features are generally italicized to give an obvious discernment. In cartographic conventions, natural features are adequate in italics such as the aforementioned hydrographic features.

[edit] Case

Case is another way of emphasizing--whether it be uppercase, lowercase or a combination of the two (or even different size points within the same case). In general, uppercase fonts denote a higher emphasis, but according to Bringhurst (1996), an uppercase initial of a word has the seniority; but the lowercase letters have the control. In other words, the strong boldness of a larger letter draws the audience into its viewpoint. The lowercase letters contain the information needed to convey further. When viewing text on maps, it is still crucial to grain the audience’s attention as a way of informing them of something other than the map(s). As for design, uppercase is much harder to read than mixed-use. In the globe example, mountain ranges should be in uppercase. When showing a larger scale, such as a region of the United States, it is useful to classify different case sizes. States should be in uppercase, with counties in small uppercase, and cities in lowercase.

[edit] Color

Color (value and hue) alterations also allow for a further emphasis on certain features. By changing the color of the font to correspond to the feature it is representing, the two become joined. If the cartographer were to label a river, the extra emphasis would be inherent if the font chosen was blue, to correspond with the blue feature (arc). On the contrary though, this is not always necessarily the case. If the cartographer chose a color of font for an ocean feature (polygon), blue would not be the obvious choice because it would appear to be washed out and thus, no emphasis. In this case, it is useful to label the feature with a more rich, bolder color (such as black font on blue polygon).

[edit] Spacing

The spacing of the letters on features also gives a more appealing map-—visually speaking. By enlarging the increments between each letter of a word, the word in turn, becomes more pronounced. In the case for a long arc feature (river), to add more emphasis on the label, the letters would need to be extended or stretched. On the other hand, in some cases, the letters would have to be condensed (shortened increment gaps) to give a more proportional label for a feature.

[edit] Kerning

Kerning (character spacing) is the distance between letters. Kerning deals with the spacing of specific letters within a word that may have spacing issues due to the shape of the letters. This doesn't necessarily space all letters in a word evenly (see spacing in previous section). Kerning is commonly done with capitol letters that might have unwanted space in-between them initially, such as AW, OA, FA, and AC. Kerning is also done with lowercase letters such as ‘ry’. ^[1]Many typeset systems automatically apply kerning to font types, but word processors such as Microsoft Word do not enable kerning by default. Un-kerned letters in cartographic design can ruin flow and even destroy the visual hierarchy of the map.

In the days of manual type, oversized letters were extended beyond the edge of the metal block to produce the desired spaces. In the world of electronic type, there is a kerning table that creates specific spaces for pairs of letters. ^[2]

As letters get bigger, so does the space in between them. ^[3] When characters become increasingly spaced out on a map, the label loses some of its hierarchy. At small scale, legibility is enhanced with increased spacing, and legibility is also increased on curves when spacing is added. Spacing can also be used to show the extent of the area labeled. ^[4]

[edit] Font vs. Typeface

Many people think of typeface and font as being the same thing; however, this is incorect. To say that a font is a typeface or a typeface is a font is like saying that a book (the physical paper object) is Hamlet (the play by Shakespere). Hamlet is not a bunch of paper and words, but words rearanged meaningfully and artistically. A book is the delivery mechanism of Hamlet, and Hamlet is the artistic creation. Font is the delivery mechanism, and typeface is the artistic creation.

[edit] x-Height

As a young person learns to write they are typically given paper with two dark lines and a lighter dotted line in the middle. The top dark line is known as the Cap Height which would be the highest point that an upper case letter would extend. The bottom dark line is known as the baseline, which is the bottom of all letters that don't have tails that extend below to what would be called the descender height (the bottom of a p,q,j). The x-height is the dotted line that splits the cap height and the baseline. It is exactly the height of the lower case x, thus it is called the x-height. This should be the height of all lowercase letters used in labeling, although some curved letter go slightly above the x-height due to the curved nature of the tops of these letters (m, n, o, etc.).

[edit] Style

Serif vs. sans serif

[edit] Serifs

The type style affects to overall look of the map and is adequately used to symbolize nominal (qualitative) data within the map. In general, style amounts to the use of serifs versus sans serifs. A serif, by definition is any of the short lines stemming from and at an angle to the upper and lower ends of the strokes of a letter. There are numerous kinds of serif. The two main types are Adnate and Abrupt. The Adnate serif is more organic and "flows" with the font. Adnate serifs are commonly distinguished with their use of curves. The Abrupt Serif — as its name suggests — is squarer and more rigid, and doesn’t flow into the base letter form.

On a map, the text that is chosen should be consistent. Generally, serif fonts are utilized to give a more regimented block body of text—similar to those used in traditional printing. Serifs are more widely used for historical information or a historical map. Serifed fonts are also widely used for body text because they are considered easier to read than sans-serif fonts in print. Serifed fonts are therefore the overwhelming typeface choice for lengthy text printed in books, newspapers and magazines.

[edit] Sans serifs

The serif counterpart is sans serifs (literally meaning without serifs). Sans serif fonts are the more modern of the two fonts. Generally, sans serifs are not for large bodies of text in print but instead, are ideal for the internet. When typefaces are digitised for use on computers, the letter forms have to fit within a relatively small pixel grid, often leading to what are called the “jaggies”. Many web professionals claim that this relatively low resolution cannot render effectively enough the fine finishing strokes of serif typefaces, and that sans serif typefaces come out cleaner and thus more legible. Books produced for children are often printed with sans serif text as teachers claim that the simplicity of the letter shapes makes them more recognizable. On the same facet, sans serifs are optimal for a more-clean appearance in such places like a header, title, or legend. In map design, it’s useful to also use sans serifs for natural features.

[edit] Weight

The type weight provides a substantial amount of emphasis of the cartographer’s choosing. Weight is important because it involves the difference between bold and regular contrast. The degree of power that is increased with weight, must be proportional to the size of the letter. If not, a letter can be too intense and thus more difficult to read. Similarly, the spacing between the letters must be extended to provide adequate to read smoothly. Bold text creates direct attention to the eyes of the audience to pronounce certain information from cartographer.

[edit] Size

The type size of fonts stresses the importance and emphasis of the intended map. Size is expressed in points through the American point system with 1 point equaling 1/72” of vertical height. Furthermore, points also show the spacing between letters, words and lines. A larger size implies more importance or a greater relative quantity; smaller denotes less importance or less quantity. For design purposes, text using a size of less than 6 point is difficult to read. On the contraire, text that is larger than 26 point is too cumbersome for a standard-size paper format. For titles, a font larger than 10 point generally allows for a good working title. Also, it is important to use at least a 2 point difference between type sizes to allow the audience to see subtle changes.

Larger sizes can be expressed in units of typography known as pica. One pica is 1/72 of a foot. This means that one pica is equivalent to 12 point units of measurement. Pica can be abbreviated as pc or P/. It would be appropriate to work with pica units as opposed to point units when creating very large maps intended to be hung on a wall or similar projects.

[edit] Effects of Size

The different size of a typeface can effect the way that the viewer reads the text. Studies have show that readers will actually read different sizes of texts different ways. Often times larger typeface will be read at a slower pace. Smaller typeface will sometimes lead to an increased reading spead and increased focus on the individual words.^[5] It is important to remember the desired effect on the viewer when labeling a map.

[edit] Legibility and Perceptibility

Legibility in cartography can be defined as the degree in which the labels or writing elements on a map are understood by the audience based on the appearance of the text. The conjugation of typeface, weight, size and case defines how effective the legibility of a map is. On the other hand perceptibility is the speed at which letters or words can be perceived and recognized. Perceptibility is more important when choosing type; this is because the letters are not displayed as blocks in a text, but rather they may be spread out, curved or interrupted by other features. An important issue that has to be kept in mind when designing a map is the difference between the readability on a computer monitor screen when designing the map and the readability of the physical printed version. In some cases, where it is appropriate to use more than one typeface on a map, it is important to keep the harmony between the different typefaces to encourage a high level of legibility. Usually two faces, one serif and one sans serif, including the two variations of bold and italic works the best; however, harmonizing the typeface to suit the purpose and the audience should be taken into consideration as well.

[edit] Placement

With all of the type in order and adequately designed, the final step is the correct placement of labels. Placement describes each feature and its subsequent label(s). For area features, it is important to curve and extend the spaces to properly fill in the areas enough that the audience can discern different areas. As a cartographic convention, labels are usually as horizontal as possible with no upside-down labels. For line features, it is useful to allow the label to conform to the line pattern. Similar to a river (e.g. geographic features), the label should flow around the edges along the line being careful not to have the letters too extended. For point patterns, the minor patterns to follow include keeping labels on/in their respective features (e.g. coastal cities with labels on the land and not ocean). The major pattern for points is the placement along the point itself. The most widely accepted pattern is to start at the center and work outward towards the northeast quadrant from the point. Many studies have been researched to address the correct strategy for the placements. The point feature cartographic label placement (PFCLP) problem offers the solutions when point boxes overlap. Many software features automatically choose label placements for the cartographer, but these are not always a fail-safe option. The use of good judgment and cartographic conventions are important to gain the best placement.

[edit] Guidelines for Labeling Point Features

Next are a series of steps or guides to use when labeling geographic features represented as points on the map.

The preferred location of a label should be to the upper right corner of the map, the second preferred location is in the lower right side, the third and fourth best options are to the upper or lower left respectively. When necessary the labels can be placed either on top or below the point symbol. The least desirable positions are directly to the left or directly the right of the symbol.

No other map feature should come between the point and its label. It is also important to place the point and its label close to each other to emphasize the association between the two.

When necessary use leader lines to connect the point and the label, preferably the lines should not touch the point, also the line must be thin and the use of an arrowhead should be avoided. If those options are not suitable for a given task, the use of a callout, a halo or a mask are encouraged.

Multiple lines of type should be centered or horizontally aligned according to the given scenario When mapping coastal areas, labels whose points fall on the land should be placed also on the land. Points falling between the land and the water must be label entirely on the land or entirely on the water.

Be wise when following the guidelines, take into consideration that the first goal is to make your map understandable.

[edit] Guidelines for Labeling Line Features

Label line features above the line you are labeling. Never place a label text upside-down(or past the vertical). For long lines place multiple labels; don’t spread text out. You can select from a number of different placement positions, offset types, and distances when placing labels for line features. You can also control whether labels must be placed exactly at the location specified by the placement parameters you set or whether they may vary within a given distance from that position. There are combinations of label positions. The first two are the following: Centered—Places-the label on the feature at the midpoint of the label. Offset—Places-the label at a default or user-defined distance or distance range from the line feature's symbol. These two placement positions are combined with the following to create all the choices: Horizontal—Places the label horizontally relative to the upper and lower map border Straight—Places the label on a straight line tangent to the feature. Curved—Places the label along the curve of the line feature Perpendicular—Places the label perpendicular to a straight line tangent to the line feature. These basic guidelines will ensure an easy-to-read map and will eliminate most causes of confusion.

[edit] Guidelines for Labeling Area(Polygon) Features

The way area labels are positioned indicate the extent of the area that is being labeled. When labeling area or polygon features there are a few rules to follow. You should spread text out to cover the whole polygon. This allows for the visual of that entire polygon to be associated with the proper label. The Label should have margins on either side that are equal to the character spaces. Also uppercase letters are better when using character spacing so area labels often should be in all capitals.Second, avoid placing labels outside the polygon; rotate text if you must. If the polygon is odd shaped or longer vertical rather than horizontal, you can rotate the text or curve it to fit withing the polygon. Third, there is always the chance that the polygon is just to small for the label to fit inside. If a polygon is too small to fit a label inside one option is to place the label as if it were a point feature. The guidelines of labeling a point feature are stated above and should be followed in such a case as the polygon being to small to fit the label assigned to it. Another option is to allow the label to extend beyond the boundaries of the polygon but place the label in such a way that it is clear which polygon it is labeling and so that the label does not hide or distort important feature. You should avoid having several horizontally aligned labels because this makes them appear like a sentence. It is important as well to make sure that now of you letters are placed is such a way so that they appear as part of a map feature or line. For example the letter "I" can appear to be part of a line.

[edit] See also

Typography

[edit] References

• Brewer, C. (2005). Designing better maps : a guide for GIS users. Redlands, Calif: ESRI Press.
• Bringhurst, Robert. 1996. The Elements of Typographic Style. 2nd ed. Hartley & Marks, Publishers, Point Roberts, WA. p.p.351.
• Evans, Poppy. 2004. Forms Folds Sizes:. Rockport Publishers, Inc., Gloucester, Massachusetts. p.p.264.
• Kameda, T. and K. Imai. 2003. Map label placement for points and curves. IEICE Transactions of Fundamentals of Electronics Communications and Computer Sciences. E86A(4):835-840.
• Krygier, John and Denis Wood. 2005. Making Maps. The Guilford Press, New York, NY and London. p.p.303.
• Lai, Poh-Chin and Anthony Gar-On Yeh. 2004. Assessing the Effectiveness of Dynamic Symbols in Cartographic Communication. The Cartographic Journal. 41(3):229-244.
• McClean, Ruari. 1997. Jan Tschichold: a life in typography. Princeton Architectural Press, New York, New York. p.p.128.
• Morison, Stanley. 1967. First Principles of Typography. Cambridge University Press, London. p.p.24.
• Ribeiro Glaydston and Luiz Lorena. 2006. Heuristics for cartographic label placement problems. Computers & Geosciences. 32:739-748.
• Rosen, Ben. 1976. Type and Typography: The Designer’s Type Book. Van Nostrand Reinhold Co., New York, NY. p.p.406.
• Slocum, Terry A. 1999. Thematic Cartography and Visualization. Prentice Hall, Upper Saddle River, NJ. p.p.293.
• Solomon, Martin. 2004. The Art of Typography: an introduction to Typo.icon.ography. Art Direction Book Company, New York, NY. p.p.256.
• Wagner, F., A. Wolff, V. Kapoor, and T. Strijk. 2001. Three Rules Suffice for Good Label Placement. Algorithmica. 30:334-349.
• http://www.w3.org/TR/REC-CSS2/syndata.html#length-units
• http://www.cdc.gov/dhdsp/maps/gisx/training/module2/files/6-module.pdf
• http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//003s00000015000000.htm

[edit] Notes

1. ↑ "Fonts : Type topics: Glossary". Adobe. http://www.adobe.com/type/topics/glossary.html. Retrieved 2011-09-16. 
2. ↑ "Kerning." thinking with type. N.p., 28 Nov 2007. Web. 17 Sep 2011. <http://www.papress.com/thinkingwithtype/index.htm>.
3. ↑ "Kerning." thinking with type. N.p., 28 Nov 2007. Web. 17 Sep 2011. <http://www.papress.com/thinkingwithtype/index.htm>.
4. ↑ Brewer, Cynthia. Designing Better Maps: A Guide for GIS Users. 1st ed. Redlands, CA: ESRI Press, 2005. 52. Print.
5. ↑ Hovde, H. (1929). The relative effects of size of type, leading and context, Journal of applied psychology, 13, 6, 600-629.