However, in some applications, the need for consistency and immediate usability has driven the development of standard sets of symbols. For example, a polygon in a choropleth map filled with a particular shade of red that means 'high income.' These symbols require effective legends and/or labels to be correctly interpreted.Ĭartographers typically have a great degree of freedom to design and implement map symbology according to their personal tastes, creativity, and innovation. Ad Hoc Symbols do not have any intuitive or commonly accepted relationship in fact, the symbol is often used only for a single map.For example, a red line to represent a highway or a cross to represent a hospital. Conventional Symbols do not have any intuitive relationship but are so commonly used that map readers eventually learn to recognize them.For example, a dollar sign to represent an ATM, or a Star of David to represent a Jewish synagogue. Conceptual Symbols directly represent a concept related to the represented feature.For example, a picture of a skier to represent a ski resort or a tent to represent a campground. Functional Symbols directly represent the activity that takes place at the represented feature.For example, a tree icon to represent a forest, or green denoting vegetation. Image or Iconic Symbols look like the real-world feature, although it is often in a generalized manner.Map symbols can thus be categorized by how they suggest this connection: For example, thick blue line ( sign) = major river ( interpretant), and this thick blue line = The Colorado River ( referent). A legend is needed to explain the meaning of the symbols that cannot safely be assumed to be intuitive.Īccording to semiotics, map symbols are 'read' by map users when they make a connection between the graphic mark on the map (the sign), a general concept (the interpretant), and a particular feature of the real world (the referent). A good symbol is easily recognizable (i.e., connected to the geographic features and concepts it represents), is aesthetically pleasing, and works in harmony with other symbols (for example, as part of a clear visual hierarchy). The choice of symbology is a crucial part of cartographic design the goal is for the map reader to spend less time figuring out what the symbols mean, and thus more time using the symbols to understand the World. Although there is no set standard on symbology for all maps, especially among thematic maps, various conventions (such as using contour lines for elevation or blue for water) are commonly followed for some classes of maps. When designing a map, the cartographer determines that a certain combination of these variables-a symbol (e.g., a dashed 0.5pt blue line)-represents a certain class of geographic feature (e.g., an intermittent stream). Map symbols are created by controlling Visual variables such as color, shape, and size the range of such variables was set forth by Jaques Bertin and subsequent cartographers. In this map the point represents populated places, the line represents roads, and the area represents urban areas This option may be re-enabled by the project by placing a file with the name '.Examples of point, line and area features on a map. NOTE: As of directory index display has been disabled by default. Contact the project administrators of this project via email (see the upper right-hand corner of the Project Summary page for their usernames) at you are a maintainer of this web content, please refer to the Site Documentation regarding web services for further assistance.Contact the project via their designated support resources.

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Symbols quantum gis