52 lines
1.5 KiB
Text
52 lines
1.5 KiB
Text
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hello world plugin
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------------------
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This is a very simple sample plugin. It is designed to help developers
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see the skeletal basics needed to achieve a functional datasource plugin.
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Code comments attempt to highlight which code is mandatory, which is
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simply recommended, and which is purely fluff used to get the plugin to
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actually show some data.
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When added to a map it provides a single point geometry representing
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the center of any query. This means that it should place a point in
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the middle of any map tile and display a "hello world!" label if used like:
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<?xml version="1.0" encoding="utf-8"?>
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<Map srs="+init=epsg:4326" background-color="white">
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<Style name="style">
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<Rule>
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<PointSymbolizer />
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<TextSymbolizer name="[key]" face_name="DejaVu Sans Book" size="10" dx="5" dy="5"/>
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</Rule>
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</Style>
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<Layer name="test" srs="+init=epsg:4326">
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<StyleName>style</StyleName>
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<Datasource>
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<Parameter name="type">hello</Parameter>
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</Datasource>
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</Layer>
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</Map>
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Or used in python like:
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from mapnik2 import *
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m = Map(600,400)
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m.background = Color('white')
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s = Style()
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r = Rule()
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r.symbols.append(PointSymbolizer())
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t = TextSymbolizer(Expression("[key]"),"DejaVu Sans Book",10,Color('black'))
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t.displacement(15,15)
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r.symbols.append(t)
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s.rules.append(r)
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m.append_style('style',s)
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ds = Datasource(type="hello")
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l = Layer('test')
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l.styles.append('style')
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l.datasource = ds
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m.layers.append(l)
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m.zoom_all()
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render_to_file(m,'test.png')
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