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section-vector-to-raster.html
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<!DOCTYPE html>
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<title>map school: Vector to Raster: a free introduction to geo</title>
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<h1><a href='./'>map school: Vector to Raster</a></h1>
<p>a free introduction to geo.</p>
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<p>It's possible to move between the two types of map data, as disparate as they might seem, and it's actually quite common: it's just not direct.</p>
<p>Typically vector data always becomes raster - what we call 'rasterized' or 'rendered' when it is displayed: computer screens and printers operate on the level of pixels, not lines or shapes. This conversion is imperfect: remember that vector data is not pixel-based, so you can never zoom in and see fuzzy features. Thus, generally, when vector data is converted into a raster format, you can't transform that raster representation back into exactly the source.</p>
<p>Sometimes we convert vector data to raster ahead of time - in order to run some kinds of analysis, it's easier to do the math on a pixel basis.</p>
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