The most reliable and effective way to combine relief with geo-political vector data is to generate a relief map in MapRender3D and generate the same vector map in Geocart. Typically the MapRender3D 1km globe data can be matched to the Geocart standard world database or for enhanced mapping using the more detailed Digital Chart of the World database. For the continental USA, the MapRender3D 100 meter USA DEM database can be matched to the Geocart National Atlas USA databases.

There are several conditions that need to be met to achieve a successful match and maintain the integrity of the finished maps.

Starting initially with the generation of the relief map, extract the DEM for the area of interest by defining exactly the Northern and Southern latitudes and Eastern and Western longitudes boundaries using the Convert utility, either from the World data supplied on CD-ROM Disc 1 Global Data or from the USA 100 meter CD-ROM's.

Always select the projection as Geographic. This is a linear projection that is equivalent to Plate Carree in Geocart. Other matching projection options are available where the projection center is not on the equator and one must use a projection than offers the capability of changing the projection center latitude parameter. This does NOT include any of the cylindrical projections, including Plate Carree. If you use a projection other than Plate Carree, great care must be taken selecting the parameters in both the Convert utility and in the Geocart map definition parameters.

Open MapRender, select the DEM created in Convert, and render the map. It is recommended that a low or medium sampling resolution is selected initially in order to get a speedy rendering, thereby varying the settings repeatedly to achieve the look and feel you need. Once you have achieved a satisfactory relief rendering, save the map by exporting the relief map in TIFF format - in the export dialog box leave all the default settings exactly as presented by MapRender3D.

We next recommend you open the TIFF image in Photoshop and do any resizing, resampling or color treatment, as the image processing capabilities in Photoshop are substantially more suitable than tweaking MR3D output.

Next start Geocart, set the projection to Plate Carree (or other selected projection) and define your Projection > Boundaries to the same area as defined for MapRender3D. Set the projection center to 0º North South (Equator) and let the East West default to Geocart's setting, or if using another projection use the same latitude as used in MapRender3D Convert.

Select the appropriate databases for your project File > Databases using either the supplied files, or DCW files or the USA database files - note both DCW and USA databases are optional extra products that can be purchased separately - see www.mac-maps.com/dwi_geod.htm . Typically the most useful Geocart databases are political borders, states and provinces, rivers and lakes, county borders, town locations and text, rail and road - some of these are available in some of the databases and not in the generic Geocart database supplied with the software. When you have selected all the layers you require, File > Export and leave the default as Adobe Illustrator 1.1, enter a file name with the .AI suffix, on the next dialog box, typically enter a value of 10 in both Horizontal and Vertical screen resolution times, and and select Vector to save the file. If the save crashes, you may have to reduce the screen resolution times to a lower value for extremely complex files.

For the last stage, using Adobe Illustrator (preferred application), Macromedia FreeHand or CorelDraw open the AI file. Although all the lines will appear the same weight and color, use the direct selection tool to select a feature - you will notice that all objects on that "layer" will be selected. This allows the vector map to have all its feature layers separated and saved as separate Illustrator layers if this is desired.

The easiest method is to duplicate the original layer and select each group of objects, delete them one by one leaving the object one wishes to preserve on that layer, then name the layer appropriately, select weight and color and then lock it. At the bottom of the layers palette create a new layer called Relief-Map. With this layer selected, File > Place the relief image created above behind the Illustrator vector layers.

The addition of lakes can be accomplished by saving the final size lakes layer and the box layer in a stand-alone Illustrator file. This lakes layer can either be rasterized and saved as a Photoshop image, then, using the Magic Wand to fill the lake areas, the lake layer can be saved with a transparent background and applied over the relief image to complete the map. Another alternative is to take the single lake layer into FreeHand and use the fill function to apply a texture or color to the lakes - for larger lakes, this may require paths to be joined in order to achieve a continuous path around the body of water and allow the fill to operate correctly. Save the filled lakes layer as an EPS file and copy it back into the final Illustrator layers stack - the box outline will ease the registration of this modified lakes layer.

The two images will not match. Lock the Relief-Map layer, unlock all other layers, Select > All (all objects will be highlighted - see above Baja California map), and using the Selection Tool, grab the corner handles to pull out or in to the corners of the vector map so that the box of the Illustrator vector map matches the corner of the relief map. Do this approximately for the upper left and lower right corners to get a rough alignment. Then zoom in, up to 6400% (Illustrator Navigator is very useful for this) to the respective corners and fine adjust the alignment. It's useful to have coastlines visible on the vector map to do a final check on the alignment and the coastline vector layer may be switched off later.

To use the layer editing capability (locking all other layers) it is very easy to modify the appearance of the map, and be able to generate maps with high degree of flexibility and appearances. In the example to the right, the relief map layer has been dimmed to 50% thereby giving a more subtle cartographic style to the map over the raw high contrast style in the line up image above. Note the the line up image above, all the layers have been selected and appear to glow and are wider than they will actually appear. This ensures that all layers are dragged proportionally and in a synchronized manner to the outline of the locked relief map on the bottom layer.

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