Step 1. Setting up a folder structure
The first step is to add a folder structure to store the map file and base materials.
- Add a folder and name it after the area you will be mapping, e.g., 'Clyne Gardens'.
- Create the following subfolders:
- LiDAR
- DTM
- DSM
- Aerial
Step 2. Setting up a new map file
To create a new map:
- Select New File in the File menu. The New File dialog box appears.
- Set the map type to Orienteering Map and load symbol set from ISSprOM 2019 4000 (or ISOM 2017 15000 if the area is particularly large).
- Click the OK button. OCAD will create a new blank map and import the chosen symbol set into it.
- Save the map in your designated folder.
Step 3. Downloading and Importing LiDAR Data
Downloading LiDAR data for your area
- Visit: https://datamap.gov.wales/maps/lidar-viewer/view#/
- In left-hand sidebar hide “Historic LiDAR Archive”
- Zoom into the area you have chosen and click on a tile that covers (or is included in) the area. A box will appear to the right side of the screen.
- Download the DTM data to the DTM Folder: Right click on the DTM data download link and Download Linked File As… to the DTM folder that you created…
- Download the DSM data to the DSM Folder: Right click on the DSM data download link and Download Linked File As… to the DSM folder that you created…
- Repeat this process for each tile covering your area.
Importing LiDAR data into OCAD
- In OCAD, navigate to DEM > DEM Import Wizard.
- Add the DTM file(s) on the left side and the DSM file(s) on the right.
- Click Next> to import and analyse the LiDAR data.
- Provide a file name for the OCAD DEM, Click Browse and store the file in the main LiDAR folder.
- Check the following options:
- Create Contour Lines
- Create Hill Shading
- Calculate Slope Gradient
- Classify Vegetation Height
The other options take a while to process so we can skip them for now. You can always come back to the DEM to explore more options later.
- Click Next. The DEM Wizard will display a screen for each of the options checked.
- Create Contour Lines
- Check Create not smoothed contours
- Contour interval: 0.5m
- Contour interval main: 2.5m
- Contour interval index: 12.5m
- Check Create smoothed contours using TPI
- Contour interval main: 2.5m
- Contour interval index: 12.5m
- Check Use different symbols for depressions
- Click Load symbols from template… and the depression options should automatically fill in. Double check the intervals look correct across all the symbols
- Click Next
and set the following:
and set the following:
- Create Hill Shading
- Under Direction, check Multi-directional
- Click the Next button
- Calculate Slope Gradient
- Leave default options
- Click the Next button
- Classify Vegetation Height
- Leave default options
- Click the Create button
- You can view the different background maps by going to Background Map > Manage and click the eye to make visible or not. read more →
OCAD will now process the data and create the different basemaps
Geo-referencing
During LiDAR processing, coordinates from the data are added to your new map's coordinates.
To ensure correct geo-referencing, set the map's coordinate system to British National Grid.
To do this go to Map > Set Scale and Coordinate System and in the Coordinate System dropdown choose British National Grid.
Now that the map is geo-referenced, any base material from other sources will load in the correct location.
Loading Google Maps Aerial Image
To load a Google Maps aerial image into your map:
- In OCAD, go to Background Map > Online Map Services…
- Define an extent
- Click on the Update button to move to Online Map Service to the centre of the drawing area.
Move and zoom the map until the desired extent is achieved. You can also enlarge the Online Map Services dialogue by clicking and dragging a corner. The image you see in the dialogue will be loaded as background map.
3. Load as background map
- Click Load as background map to load the image in the dialogue as background map.
- Save it in the Aerial folder that you created earlier.
- OCAD changes to Draft mode afterwards.
Navigating OCAD may have a bit of a learning curve..
Hover over the various menus to see what each thing does.
Updating existing maps
You could apply the same process to help with updating a map.
Simply open the existing orienteering map file instead of creating a new map and so long as it is geo-referenced, the background maps will open in the correct place.
See https://www.ocad.com/wiki/ocad/en/index.php?title=Updating_Orienteering_Maps_in_OCAD for more information.