This article is about geographic maps. For maps in mathematics, see function (mathematics).
Basic map characteristics tell the reader where an object is (location) and what the object is (its attributes). Maps are also simplified reductions and abstracions of selected real world areas that have attributes of scale, resolution, and are defined onto a projection that distorts the curved surface of the earth onto a flat surface. Different objects represented on the map are classifed and symbolized so that the map user can easily use the map as a database of geographic information.
Every map has a scale, determining how large objects on the map are in relation to their actual size. A larger scale shows more detail, thus requiring a larger map to show the same area (a smaller number after the colon means a larger scale: 1:10,000 is a larger scale than 1:25,000).
Representing surfaces 1) contours 2) hill shading (shade from the north-west)
Other kinds of maps 1) morphometric maps - slope - aspect - roughness 2) terrain unit map - mountains - valleys - plains 3) Mimetic/Pictographic
responibilities of readers and map makers makers - select, simplify, and symbolize users - read, analyze and interpret
The spatial resolution of a map is the size of the smallest feature on the map that can be correctly represented without distorting its relative size. Maps with a high resolution have more more pixels (detail) per unit area. The accuracy of a map is a measure of how close a mapped value is to reality. And map precision describes how fine the measurements are (2,145 kilometers is more precise than 2,100 kilometers).
If the map covers a large area of the earth's surface, it also has a map projection, a way of translating the three-dimensional real surface of the globe to a two-dimensional picture. The most commonly used is the Mercator Projection; other popular projections are polar and a variety of equal-area projections.
There are four different types of maps. General reference maps are usually small scale maps that depict very large areas. A good example is an atlas. Thematic maps are used for special purposes such as showing the distribution of certain selected types of demographic or scientific data on a map that follows a theme. This is the main type of map that is made using GIS applications and is the result of performing some type of analysis. Charts are maps that represent the world in a way that are useful for navigational purposes. Plans are used by governments and buiders to layout construction projects (blueprints).
Maps covering parts of the earth tend to be either political or geographical. The most important purpose of the political map is to show national borders, and the purpose of the geographical is to show features of [[physical geography]]. Geological maps show not only the physical surface, but characteristics of the underlying rock, fault lines, and subsurface structures.
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Design Principles To be an effective means in the conveyance of geographic data, maps must be legible, provide visual contrast between elements, have good figure to ground organization, must have a basis for differentiating elements, have a closed form, present familiar elements in recognizable ways and have a good contour interval[?] (for topographic maps). Differences in detail should be expressed by using different element sizes and through hierarchical organization. There are three different categories of organization in maps; seterogramic, extensional and subdivisional.
Hierarchical organization - this is how you structure your map -- stuff that is most important needs to stand out three types: 1) Stereogramic (color; brighter stands out, more saturate and lighter) 2) Extensional; used to show a ranking of symbols (thickness) 3) Subdivisional (states nested in countrys, countys nested in states)
Map design involves an exploration of the purpose of the map which includes the substantive purpose (logical goal: whether the needed data are presented) and the affective purpose (emotional goal: how the map is processed by the reader). The reality of map design has to deal with awkwardly shaped areas, areas on the map with overly dense data, data availability, the end user viewing distance (example: is this the map a wall map or a book map?), conditions of use (example: is this map going to be used in moist environment?) and technical limitations such as the amount of time alloted to make the map, its cost, and the ability of software to do accomplish the map's goals.
The planning process in map design is an involved process. The cartographer must draw a preliminary sketch, help guide the layout decisions (desktop GIS layout tools make layout experimentation much easier), evaluate design options, develop several prototypes for review, find out if the map is a self standing product or will be part of a set, consider the number of copies that will be needed, and determine if the map will be folded or bound.
The optimal visual ratio of a map is about 3:5.
The map legend does not need to list all the elements and features of the map, but only the ones that are needed to affect its purpose. In addition, a properly constructed legond doesn't need to have the word "legend" in its title and it is not necessary to have a box around a well-constructed legend. All maps should have some indicator of scale but the scale should be no more complex than needed to serve the map's purpose. Since most maps are by convention oriented with the top of the map facing either grid, geographic or (less often) magnetic north, a north arrow is not too important and not needed at all if a distinct map grid is present.
Contextual elements (such as title, scale, legond etc.) are positioned relative to the neatline. In reference maps[?] (such as a road atlas[?]) the contextual elements go outside of the neatline so that information is not lost. In thematic maps[?] it is common to place contextual elements in the parts of the map that do not contain data relevant to the map's theme.
design objectives for quantitative use of color
The cartographer needs to know something about color theory[?] which deals with how the different colors of the electromagnetic spectrum function in concert with the human eye and brain in the conveyance of information. The dimension of color is defined by its hue (what the color is), [[color saturation | saturation]] (its intensity and purity), and value[?] (how bright the color is).
Other imporant considerations deal with the [[opponent process theory of vision]], additive vs subtractive color[?] and [[color model]]s (HSV[?], RGB, [[CMYK color model|CMYK]] and CIE[?]).
Color progressions
Complements: Red/green, blue/yellow
Quantitative use of color
Categories of color progressions
Single hue progresson
Two hue progression (Bipolar verson)
Comlementary hue version
Several hues: Partial spectral hue progression
Blended hue progression
Sybolic connotation of color
Number of step is a progression
Pattern progression
Qualitative use of color
Placing text on color
Color conventions: Water is blue. Green is vegetation. Brown is land. Yellow is indicator of dry.
Basic graphic elements: points, lines and polygons
Classes of symbols
The measurement level used in maps is either nominal (names), ordinal (ordering relationships), interval (the distance between objects) or ratio.
Dimensionality of data
This can be done wih a single hue progession where the low values are light and the high values are dark.
Two hues: neutral color in center to two dark endpoint hues
Nominal symbols (qualitative)
Ordering symbols (quantitative)
Mimetic pictograh vs. geometric symbols Symbolizing feaue attribute volumes
Statistical surface: Mathematically continuous distribution over an area.
Functions: locative, nominative and ordinal Elements of text: size, color, style, form Style: Font (serif or sans-serif) Form: Bold, italic, case, underline
Don't want to use more than two styles.
Form conventions: Use uppercase sparingly (water bodies, or widely spaced lettering). Lowercase is easier to read. Italics is used for water (gives the indication of flow).
Size conventions; no smaller than 5 points. Use the largest text that doesn't crowd the map.
Use text size to set up hierarchies.
Use color to link text with features.
text is all on the land or all on the water. If you can see the curvature of gradicule then align the text to it.
If needed repeat the names of things is they are long (such as river)
Typography
Elements of typography
type style
San serif styles are sometimes called Gothic
Style conventions for text
Type form
Case
Slant or italic
Type size
general rules for positioning text
Labelng points
5 2 1 4 3 6
Labeling lines
Because maps are abstract representations of the world they are not neutral documents and must be carefully interpreted.
In First person shooters and other computer games "map" refers to the current territory (including buildings, entities, spawn points, etc.) as well as the objectives that must be completed. For example, the map "de_dust" in Counter-Strike includes the brushes[?], textures, bomb sites, spawn points, and backgrounds.
Printing
Printing is an industrial process[?] for reproducing copies of an image, typically with ink on paper using a printing press.
Printing using a printing press dates back to the 15th century in Europe, although the technique is believed to have been developed and used earlier in China. For a fuller history of printing, see the printing press article.
The term is also used for the act of printing a document using a [[laser printer]] or other computer printer. In recent years, computer printing and industrial printing processes have converged, leading to the development of digital printing[?].
The term is often also used for the artistic process of printmaking.
tint screens - image shops used to tint screens which wer preferated sheets
Morie pattern - results fro bad angleing of screens - it is an objectionale secondary pattern
Rosee patter - results fro a good angleing of screens
Dithering - math technique used to give the illusion of a continuous tone on a computer screen or printer device
two varieties of dithering - Spiral dithering - requires a very high resoltion about 2400 di - Random dithering - lower resolution 300 -120 dpi
Spiral dithering - spirals out from the center to create a dot. - requires very high resolution - just as with tint screens,, after 50% the cells are switched
digital color production - color s produced on a compter screen by firing electron guns at phosphors which eit ligtht when struckk. three electron gus; red greeen, and blue
A frame buffer is a section in the computer menory tat stes a vinary represtation of the cocomputer screen in a multi dimensional arry
bit plan
how many colors are possible? - depends on the numbr of bity planes in th efram buffer
there are eith bit plans per color - there are 2^8 (256) shade available for each color - hence the typical reage of values is 0-255 256x256x256 = 16.777,216 colors
Simultaneous contrast - contrast will confuse color shades - this dictates the number and range of colors
Four-color printing
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