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MapnikCoreConcepts.md

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+# Core Concepts of Mapnik
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+Mapnik can be used with XML, Python or C++, but the key concepts are the same across these technologies. For details on how to use the different APIs, see [[LearningMapnik]].
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+Mapnik creates maps. The *map* object is therefore central to Mapnik's API. The map object provides methods for rendering a map to a graphical output format (usually PNG or PDF).
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+Maps are (mainly) made up of arbitrary numbers of *layers*. Each layer has a *datasource* that provides the geometry data (provided by one of several *plugins* that read and parse the data). For rendering the data, each layer can be assigned one or multiple styles.
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+A *style* defines how the objects in a layer are rendered. A style contains one or more *rules* that can optionally constrain its output to *filter* out a subset of the objects provided by the layers datasource, for example to show only these objects who have a specific attribute set. Filters are optional – a common case for simple maps is to have one rule for each layer without any filters. Each rule holds one or more *symbolizers* which are responsible for actually drawing geometry in the output. Depending on the symbolizer class and settings, geometry can be rendered in a variety of ways.
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+## Further Reading
+
+- [[SymbologySupport]]
+- [[GettingStartedInPython]]
+- [[Mapnik API]]