cartographydemgoogle mapsshaded-reliefvector
I am looking for a good workflow on how to represent relief on a map as vector (e.g. for further processing in Adobe Illustrator or Inkscape). My inspiration is the present google maps at zoom level 12, since this looks like it is based on vector graphics:
https://maps.google.de/?ll=47.27853,10.686607&spn=0.179816,0.41851&t=m&z=12
Starting with some free SRTM elevation data, what would be the best way to achieve such a result?
(2008) Updated hillshade toolbox by Aileen Buckley, Mapping Center Lead, Esri. Swiss style shaded relief and Multi directional oblique weighted (MDOW) relief toolboxes for ArcGIS 9.2 and 9.3
(2010) Using curvature rasters to enhance terrain representation by Aileen Buckley, Mapping Center Lead, Esri. "using curvature rasters with hillshaded surfaces helps to capture local variations ... to help us to better see the detail in the high slope areas"
(2014) Introducing Esri’s Next Generation Hillshade by Rajinder Nagi, Esri. "The Multi-Directional Hillshade is available on ArcGIS Online and can be easily added to your desktop or web apps. It is currently implemented as a custom raster function on the World Elevation Service, and requires an ArcGIS Organizational subscription account to access."
(2015) Take your terrain mapping to new heights by Kenneth Field, Senior Cartographic Product Engineer, and Linda Beale, Esri. A culmination of hillshade and terrain research from many years in a single package. Includes a zip file from ArcGIS Online that contains the toolbox, sample data, documentation and also an ArcMap Map Document (v10.x) and ArcGIS Pro Project.
(2018) Multi-directional hillshade function is now available out-of-the-box in ArcGIS Pro (1.4 or later) and ArcMap 10.6. It can be invoked by choosing the Multidirectional option from drop down menu of Hillshade Type parameter (in Image Analysis function editor after applying the Hillshade).
For relief shading in GRASS, better use r.shaded.relief. It comes by default with light from west to east. Like this (SRTM example):
For my perception the valley looks ok in this example. The colortable comes from r.colors (there are "terrain" and "srtm", see here for examples of these color tables).
Best Answer
This is how I managed to get it done in Qgis:
Generate the Hillshade using Raster>>Terrain>>Hillshade Analysis.
The Hillshade that was generated in my case, had values from 25 to 190, with values clustered around 150. Using the Histogram, I figured out what would be the values of the 4 classes.
The Hillshade now needs to be reclassified. In Qgis 1.8, there was a plugin called RasterCalc, which has not been updated to QGIS 2.0 API. SO I fired up Qgis 1.8 and reclassified the Hillshade Raster into a new raster with 4 classes.
I used Raster>>Conversion>>Polygonise to convert the raster from step 3 to a polygon shapefile.
Once you have a shapefile, There are several ways of exporting to Illustrator, most of which are lossy.
I created a map in map composer and then exported that to pdf, which I belive can be opened by Illustrator. You can also export to SVG, which could also be used.
Please note, that I wasn't too happy with my polygon output, so I'm not sure how useful this procedure would be.