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arma3:terrain:qgis-real-world-data-tutorial [2019-01-20 10:01]
snakeman fixed typos.
arma3:terrain:qgis-real-world-data-tutorial [2019-02-11 02:57] (current)
snakeman added new update from ross.
Line 36: Line 36:
 **For single tile export** **For single tile export**
  
-  * Load in just the '​.map'​ files generated ​in Terra Incognita into QGIS+  * Load in just the '​.map'​ files generated ​from Terra Incognita into QGIS
   * Merge rasters   * Merge rasters
   * Obtain extents from square feature   * Obtain extents from square feature
Line 43: Line 43:
 **For 4 tile export (large projects 40960 and above)** **For 4 tile export (large projects 40960 and above)**
  
-  * Load in just the '​.map'​ files generated ​in Terra Incognita into QGIS+  * Load in just the '​.map'​ files generated ​from Terra Incognita into QGIS
   * Merge Rasters   * Merge Rasters
   * Create grid -- 2 x 2 Feature   * Create grid -- 2 x 2 Feature
Line 143: Line 143:
  
 import os\\ import os\\
-os.system(r%%'''​%%gdalwarp ​**-t_srs EPSG:​32620** -wo SOURCE_EXTRA=1000 ​**-tr 5.0 5.0** -srcnodata "​-9999"​ -r cubic -of GTiff **-te 576787.687480 1841104.815839 597267.687480 1861584.815839 D:/​Arma/​Heightmaps/​Opentopo/​output_srtm.asc** **D:/​Arma/​QGIS/​Montserrat/​converted.tif**%%'''​%%)+os.system(r%%'''​%%gdalwarp -t_srs EPSG:**32620** -wo SOURCE_EXTRA=1000 -tr **5.0 5.0** -srcnodata "​-9999"​ -r cubic -of GTiff -te **576787.687480 1841104.815839 597267.687480 1861584.815839 D:/​Arma/​Heightmaps/​Opentopo/​output_srtm.asc** **D:/​Arma/​QGIS/​Montserrat/​converted.tif**%%'''​%%)
  
 Some explanation of the key parameters: Some explanation of the key parameters:
Line 305: Line 305:
 **Heightmap (.asc) edits** **Heightmap (.asc) edits**
  
-Open your asc and change the following:+Open your **asc** in notepad ​and change the following ​to ensure it loads in Terrain builder:
  
 {{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-14.png}} {{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-14.png}}
 +
 +Save to a new asc, whilst maintaining the original for use in your QGIS project space
  
 Before loading the asc file into Terrain Builder, delete the .prj file. Otherwise it will not import into TB. Before loading the asc file into Terrain Builder, delete the .prj file. Otherwise it will not import into TB.
Line 331: Line 333:
  
 {{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-11.png}} {{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-11.png}}
 +
 +===== Preparing Road Shapefile =====
 +
 +**Load in road shapefile**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-37.png}}
 +
 +**Clip vector to square shape**
 +Top Menu - **Vector** > **Geoprocessing Tools** > **Clip**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-38.png}}
 +
 +Save features from clip to new shapefile -  selecting correct **CRS UTM-20**\\
 +
 +Top Menu - **Layer** > **Save As**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-39.png}}
 +
 +**Set road shapefile to CRS - 31N**
 +
 +RMB on road shapefile > **Set CRS** > **Set Layer CRS**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-40.png}}
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-41.png}}
 +
 +**Set QGIS project CRS to UTM- 31N (bottom right corner):**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-42.png}}
 +
 +**Collect extents from your square shapefile:​**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-43.png}}
 +
 +Extent: (**576787.687480**,​ **1841104.815839**) - (597267.687480,​ 1861584.815839)
 +
 +The first two values will be used in the v.transform step below.
 +
 +
 +**v.transform on road shapefile using calculated extents from square shapefile**
 +
 +Your heightmap asc must adhere to Terrain Builders required values of **easting 200000** and **northing 0**
 +Your road shapefile also needs to line up to the same values - we will use **v.transform** to achieve this
 +
 +So taking the extent values we grabbed in previous step -\\
 +We will do the following calculations to bring these values to (**200000** and **0**):\\
 +**Easting: ​ 576787.687480 ​ - 376787.68748 = 200000**\\
 +**Northing: 1841104.815839 - 1841104.815839 = 0**\\
 +
 +**-376787.68748**\\
 +**-1841104.815839**
 +
 +
 +Having figured out the correct figures plug them into the **v.transform** process
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-44.png}}
 +
 +Drag and Drop into QGIS your heightmap asc - the one you are able to load into Terrain builder - already adjusted to (**200000**,​ **0**)
 +
 +Set CRS on above asc to **UTM - 31N**
 +
 +Right click on asc in **Layers** > **Zoom to Layer**
 +
 +In **Layers** panel drag the asc below your **transformed road shapefile** - so you can see the roads layered above the asc
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-45.png}}
 +
 +Your roads should now be perfectly aligned above your heightmap
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-46.png}}
 +
 +==== Setting ID and ORDER fields ====
 +
 +RMB on transformed shapefile layer > Toggle **Editing**
 +
 +RMB on transformed shapefile layer  > Open **Attribute Table**
 +
 +
 +Click **Delete field** - select all fields and press **OK**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-47.png}}
 +
 +New Field - Name '​**ID**'​ - length **0**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-48.png}}
 +
 +New Field - Name '​**ORDER**'​ - length 0
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-49.png}}
 +
 +Toggle - **Multi Edit mode**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-50.png}}
 +
 +ID - Enter **0** - click **Update All**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-51.png}}
 +
 +Select ORDER from drop down - Enter **1** - click **Update all**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-52.png}}
 +
 +Click - **Switch to table view**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-53.png}}
 +
 +Click **Save**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-54.png}}
 +
 +RMB on transformed road shapefile - **Toggle Editing** to save the changes
 +
 +
 +**Switching to Terrain Builder -**
 +
 +
 +**Load your road shapefile**
 +
 +Top menu - **File** > **Import** > **Shapes**
 +
 +Click **OK**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-55.png}}
 +
 +Perfectly overlaid within **Terrain builder:**
 +
 +{{https://​pmc.editing.wiki/​images/​Ross-QGIS-Tutorial-56.png}}
 +
  
 **Coming Soon:** **Coming Soon:**
-  * Road shapefile creation 
   * Assisted image classification - for creation of mask   * Assisted image classification - for creation of mask
   * 3d preview using Qgis2threejs   * 3d preview using Qgis2threejs
arma3/terrain/qgis-real-world-data-tutorial.txt ยท Last modified: 2019-02-11 02:57 by snakeman