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Shape File Import now in OCAD 12 Orienteering

Import ESRI Shape files on OCAD 12 Orienteering edition

This very useful function was previously only in Professional edtion. From OCAD 12 v12.1.2 it is in Orienteering edition. The only difference from Professional is that although you can view the associated dBase file data during the import set up, that file will not be imported for further processing. Is that an issue? Not for orienteering maps as it just prevents you loading text such as road names.

Note that Shape datasets come as a package of files often including metadata and other information. Using Shape dataset TR_ROAD as an example, this is the file group that must be present when you import.

  • TR_ROAD.dbf
  • TR_ROAD.prj
  • TR_ROAD.shp
  • TR_ROAD.shx

Shape is a great tool for georeferencing

Grounded Patterns near Bendigo

Not an ESRI shape file 🙂

New map

To georeference a new map, simply import a relevant Shape file into an empty OCAD map file, assign (New Offset in the import panel) the Shape file co-ordinates to the map file and you are done. You don’t even need to transform nor keep that data.

Existing map

I import VicMap transport (or just the road layer) and use intersections of main roads to georeference an existing map. If main roads are not available on your map area then you can use lesser roads with caution as I find they are less reliable. A good double check if using lesser roads is to check against georeferenced aerial images such as from Nearmap.

Shape vs DXF

Until I upgraded to Professional version, I used DXF data from the state mapping agency and local government. VicMap had to convert their Shape data to DXF for me. A DXF file is very restrictive in its content vs a Shape file as it contained just one of the ‘layers’ at a time (I don’t know whether this is generally true or just the way VicMap worked). For example, index contours had to be provided as an additional DXF file with additional processing. With a Shape elevation file, I get the index contours plus the interval contours in one import.

The apparent advantages of Shape files was the key reason I upgraded. Within 2 weeks I discovered that the advantages over DXF files were even greater than I had thought. The luxury of importing a complex dataset that is perfectly referenced to others just imported was magic. That time saving was significant for a mapper who at that time also had a day job.

Shape data accessibility

VIC Gov Spatial Data selection

VIC Gov Spatial Data selection

Most sources of GIS data use ESRI Shape data files for transfer. ESRI’s ArcGIS is the most commonly used GIS platform worldwide. Organisations that do not use ArcGIS still conform to many ESRI conventions.

So whether you go to your local council or a forestry company, you will probably find they much prefer to provide data in Shape file format.

The Victorian state mapping agency has public online data access at data.vic.gov.au  Here is my pdf guide to accessing it.  You select Spatial Data to get at topographical data. Then you make various selections to filter data. I find this cumbersome when trying to get at the topo type data especially as some key datasets do not show up (VicMap haven’t yet fixed it).

So I suggest that you get a Spatial datamart login as that gets straight to business with this opening screen DataSearch VIC Spatial datamart Victoria .  Anyone can establish a login.

If you can supply similar links to access topo data in your state then please let me have those and I will publish them on this website.

Which topo datasets?

My most frequent topo datasets

My maps are principally for mountain bike orienteering and tourism trail networks. However, a number of the datasets I use can also be relevant to preparing a base map for orienteering and, as we have seen above, to quickly georeference a new or existing map.

  • elevation – contours, index contours, morphology (banks, cuttings and the like). Spot heights and trig points if relevant.
  • hydrology – rivers, streams, watercourses, channels, lakes, ponds, dams … (not accurate for orienteering maps but may be a useful base).
  • transport – roads, rail, infrastructure (bridges …).
  • features – I use Built Up Area (BUA) to define residental areas.
  • vegetation – useful for trail and tourism maps, too general for orienteering.
  • property – great for locating private property and public space boundaries.

    Creswick trail map snip

    Creswick trail map mostly from Shape

Some dataset content notes

Most datasets have multiple layers. For example, the VIC transport dataset allows me to select on road classification. There are 12 classes ranging from freeway to cycle track. I have a .crt file that automatically transforms those layers to their relevant symbol. You could create a single .crt file to handle all the above transforms although I find a separate one for each dataset to be more manageable.

Some of the above datasets contain a number of subsets. For example, the VIC Transport dataset comprises;

  • 3 x airport datasets
  • 2 x rail datasets
  • 3 x road datasets

Some of these are available as separate datasets. Thus generally I use just TR_ROAD and if there is rail in the area I also add TR_RAIL. This simplifies processing.

Useful resources

OCAD blog on Shape import for Orienteering edition

OCAD 12 wiki on Shape import for Orienteering edition

Ken’s mindmap of import of VicMap shape files into OCAD

Other states are likely to have different names for elements described in the above mind map. But the principles should be the same. The mind map may appear daunting but it represents considerable detail that I rarely use in the normal course of importing Shape datasets.

Wikipedia on Shapefiles

The colourful featured image of this post is a screen snip of Shape file hydro data of my local council area. This was displayed using CADViewer. I have used this excellent app by SA based Guthrie CAD for some years. It gives me a fast view of a Shape file (and DXF,  PDF)  so I can quickly detect missing content or incorrect coverage without having to import into OCAD. The information button on screen enables useful info on an element that you select on screen.  Free trial.

Guide to free spatial data – VIC

 

 

 

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