# TouchTerrain standalone in a jupyter notebook¶

Chris Harding, Feb 8, 2021 (charding@iastate.edu)

• This jupyter notebook runs a standalone version of TouchTerrain, similar to TouchTerrain_standalone.py
• This notebook needs to be run in Python 3.x
• If you're using this via the touchterrain_jupyter docker container, ignore all the install stuff that follows. The image will already contain nearly all packeges, except for the touchterrain module itself, which you should already have installed via the install_touchterrain.sh shell script. You might want to rename/save this notebook into something other than TouchTerrain_standalone_jupyter_notebook.ipnb b/c if you ever update the touchterrain module from github (update_touchterrain.sh) it will overwrite it!
• Use pip to build and install a package called touchterrain (all lowercase!), which contains all functions needed to run in standalone and in server mode. This will also install all dependencies needed(!)
• you can run pip either in a terminal or inside a jupyer cell (see next cell)
• to run it in a separate terminal, cd to the folder that contains the setup.py file (which will contain a folder called touchterrain)
• enter: pip install .
• note the . at the end, which will make pip run the script in setup.py
• this will install all dependencies (including earthengine-api)
• on Windows, if pip gives you trouble with gdal, get the whl file from here and install it separatly with pip install <whl file> then go back and try the full install again
• on Linux/Mac, gdal should be avaiable via conda-forge and does require a C-compiler
• there are two optional modules which you may want to install via pip as well:
• pip install geemap will allow you to use an interactive in-cell map to digitize the print area
• pip install k3d will allow you to preview your STL file in a 3D viewer
In [ ]:
# if you have already installed touchterrain, skip this cell!

# Uncomment these 2 lines and run this cell (Shift-Enter) to have pip install the touchterrain module and
# all its dependencies. Warning: this can take a a while! You may not see any message during the install
# but you should see the full log when pip is done (or when you got errors)

#import sys
#!{sys.executable} -m pip install .


### Preparing to use Google Earth Engine online DEM rasters¶

• You don't need this if you only want to import terrain from locally stored raster files (geotiffs)!
• TouchTerrain can use DEM data from Google Earth Engine (given the corners of the area), but you need to first request a developer account and set up an authentication file
• (This dev account is different from your standard Google (Gmail, etc.) account!)

------------------- Not sure if this is still needed ..........

------------------- Not sure if this is still needed ..........

• ee will be initialized (ee.Initialize()) later (inside TouchTerrainEarthEngine.py)
• in ee.Initialize() it will run an authentication to check with your Google dev/service account.
• The authentication requires that you have this authentication file in place: <your home folder/.config/earthengine/credentials
• This credentials file is created by running ee.Authenticate() once(!).
• To create the credentials file uncomment ee.Authenticate() in the next cell and run it.
• After you have done this ONCE, you should not have to use ee.Authenticate() anymore, so comment it out again. (#ee.Authenticate())
• You will still need to run this cell for its import ee every time, just not the ee.Authenticate() part
In [ ]:
import ee # earthengine-api should have been installed via pip ealier
#ee.Authenticate()

• When you run: ee.Authenticate() this text should appear and you should be redirected to a webpage:  To authorize access needed by Earth Engine, open the following URL in a web browser and follow the instructions. If the web browser does not start automatically, please manually browse the URL below.



• the web page will have you select a Google account for use with ee and give you a code
• paste in your code here: Enter verification code: <your code> and hit Enter, you should get Successfully saved authorization token.
• this will create the <your home folder/.config/earthengine/credentials file you need to authenticate.
• import TouchTerrainEarthEngine (below) will internally run ee.Initialize() which uses this file to authenticate. If you see: EE init() worked with .config/earthengine/credentials, you're ready to use Earth Engine's online DEM sources.

## Running Touchterrain standalone (local and online DEM data)¶

• Put your settings into the dictionary below and hit Shift-Enter
• Note, however, that the settings given below are in Python syntax, whereas the ReadMe describes the JSON syntax used in the config file
• Both are very similar, except for None and True/False
    Python:  JSON:
None     null
True     true
False    false
In [ ]:
# import packages
import os, sys
from pprint import pprint

# touchterrain should have been installed via pip earlier
# this will also run ee.Initialize() and should show:
#  EE init() worked with .config/earthengine/credentials
# If you don't plan on using ee you may get a warning, which you can ignore.
from touchterrain.common import TouchTerrainEarthEngine as TouchTerrain

In [ ]:
args = {
# DEM/Area to print

# A: use local DEM raster (geotiff)
#"importedDEM": "stuff/pyramid.tif",  # path to the geotif in relation to where this notebook sits

# B: use area and a DEM online source via EarthEngine
"importedDEM": None,
"DEM_name": "USGS/3DEP/10m",   # DEM source
# the following defines the area, but you can also define it by hand (see digitizing)
"bllat": 44.50185267072875,   # bottom left corner lat
"bllon": -108.25427910156247, # bottom left corner long
"trlat": 44.69741706507476,   # top right corner lat
"trlon": -107.97962089843747, # top right corner long

# 3D print parameters
"tilewidth": 120,  # width of each tile in mm, (tile height will be auto calculated)
"printres": 0.4,  # resolution (horizontal) of 3D printer in mm, should be your NOZZLE size or just a bit less!
# Using something like 0.01 will NOT print out a super detailed version as you slicer will remove
# super fine details anyway! You'll just wait a long time and get a super large STL file!

"ntilesx": 1, # number of tiles in x
"ntilesy": 1, # number of tiles in y

"basethick": 0.6,   # thickness (in mm) of printed base
"zscale": 2,      # elevation (vertical) scaling
"fileformat": "STLb",  # format of 3D model files: "obj" wavefront obj (ascii),
#   "STLa" ascii STL or "STLb" binary STL.
#   To export just the (untiled) raster (no mesh), use "GeoTiff"
"zip_file_name": "myterrain",   # base name of zipfile, .zip will be added

# Expert settings
"tile_centered": False, # True-> all tiles are centered around 0/0, False, all tiles "fit together"
"CPU_cores_to_use" : 0, # 0: use all available cores, None: don't use multiprocessing (single core only)
# multi-core will be much faster for more than 1 tile
"max_cells_for_memory_only" : 5000^2, # if number of raster cells is bigger than this, use temp_files instead of memory.
# set this very high to force use of memory and lower it if you run out of memory
"no_bottom": False,   # omit bottom triangles? Most slicers still work and it makes smaller files
"no_normal": True,    # Don't calculate normals for triangles. This is significantly faster but some 3D model viewers may need them.
"bottom_image": None, # "stuff/TouchTerrain_bottom_example.png", # 1 band greyscale image used for bottom relief
"ignore_leq": None,   # set all values <= this to NaN so they don't print
"lower_leq": None,    # e.g. [0.0, 2.0] values <= 0.0 will be lowered by 2mm in the final model
"unprojected": False, # don't project to UTM (for EE rasters only)
"projection": None,   # None means use the closest UTM zone. Can be a EPSG number (int!) instead but not all work.
"only" : None,        # if not None: list with x and y tile index (1 based) of the only tile to process
#   e.g. [1,1] will only process the tile in upper left corner, [2,1] the tile right to it, etc.
"importedGPX": [],    # list of gpx path file(s) to be use (optional: see next cell)
}
########################################################

# if we want to work on a local raster, get the full pathname to it
if args["importedDEM"] != None:
from os.path import abspath
args["importedDEM"]= abspath(args["importedDEM"])


### Optional: Drape GPX path file(s) over the terrain (thanks to KohlhardtC!)¶

• you can drape one or more gpx (path) files over your terrain
• the gpx file(s) have to be part of list (importedGPX)
• gpxPathHeight (meters) defines how much a path is elevated above the terrain. Use a negative number to create a trench.
• gpxPixelsBetweenPoints (meters) lets you reduce the number of point in your path to place a point only every X meters. This can help to simplify complex patterns.
• gpxPathThickness (meters) controls the thickness of the path
In [ ]:
# Note: you must uncomment the last line in this cell to actually use these gpx settings!
from touchterrain.common.TouchTerrainGPX import *
gpx_args = {
# Area for using the example GPX test files
"bllat": 39.32205105794382,   # bottom left corner lat
"bllon": -120.37497608519418, # bottom left corner long
"trlat": 39.45763749030933,   # top right corner lat
"trlon": -120.2002248034559, # top right corner long

"importedGPX": # gpx example files.
["stuff/gpx-test/DLRTnML.gpx",
"stuff/gpx-test/DonnerToFrog.gpx",
"stuff/gpx-test/CinTwistToFrog.gpx",
"stuff/gpx-test/sagehen.gpx",
"stuff/gpx-test/dd-to-prosser.gpx",
"stuff/gpx-test/alder-creek-to-crabtree-canyon.gpx",
"stuff/gpx-test/ugly-pop-without-solvang.gpx",
"stuff/gpx-test/tomstrail.gpx"
],
"gpxPathHeight": 10,  # Currently we plot the GPX path by simply adjusting the
# raster elevation at the specified lat/lon,
# therefore this is in meters. Negative numbers are ok
# and put a dent in the mdoel
"gpxPixelsBetweenPoints" : 20, # GPX Files haves a lot of points. A higher
#number will create more space between lines drawn
# on the model and can have the effect of making the paths look a bit cleaner
"gpxPathThickness" : 2, # Stack paralell lines on either side of primary line
# to create thickness. A setting of 1 probably looks the best
}

# uncomment the next line if you want to use gpx_args!
#args = {**args, **gpx_args}; print(args) # merge gpx_args into args, ** unrolls dicts


### Optional: Show map and digitize print area shape (box, circle or polygon)¶

• the next 2 cells will show you a hillshaded Google map and will let you manually define a shape, either a rectangle (box), a circle or a polygon
• it will show you a red box of the area defined earlier (with bllat, etc.) in case you want to digitize inside it. However, you're free to digitize anywhere on the map! Your digitized shape will always override the red box.
• This requires the geemap module. To install it, type pip install geemap into a OS terminal

• Run the next cell to see the Google map

• ignore any Exceptions with with oauth2client >= 4.0.0 or google-auth, they are bogus
• On the left, use the Draw a Rectangle, Draw a Circle or Draw a Polygon to define the shape of your print area
• Run the cell below the Map to make a GeoJSON polygon and add it to args. (If you don't want to use the shape (or didn't digitize any) and want to use the red bounding box, just skip this step.)
• Run the processing cell
In [ ]:
import geemap
center_lat = (args["trlat"] + args["bllat"]) / 2
center_lon = (args["trlon"] + args["bllon"]) / 2

Map = geemap.Map(center=(center_lat, center_lon), zoom=7) # Create an interactive map
image = ee.Image(args["DEM_name"]) # Add source DEM dataset

# You can change the parameters in the next 2 lines for you needs and re-run the cell
azimuth = 315   # horizontal angle of (direction to) sun
elevation = 35  # vertical sun angle
vis_params = {'min': 0,'max': 255,}
shown=True, opacity=0.5)

# show bounding box
rect = ee.Geometry.Rectangle(
args["bllon"], args["bllat"], args["trlon"], args["trlat"])
rect_feature = ee.Feature(rect)
Map.addLayer(rect_feature, {"color": 'FF0000'}, "bounding box", opacity=0.5)

# add gpx lines if used
if len(args["importedGPX"]) > 0:
multi_line_string = convert_to_GeoJSON(args["importedGPX"])
mls_feature = ee.Feature(multi_line_string)
Map.addLayer(mls_feature, {"color":'00FFFF', "strokeWidth":"1"}, "GPX line", opacity=0.9)

Map # makes the interactive map show up as output of this cell
# Note: ignore exceptions with oauth2client >= 4.0.0 or google-auth

In [ ]:
# in the map GUI above, digitze a rectangle, circle or polygon, then run this cell
# (if you screw up, just digitize a new shape and run this cell again, it will always use
# the last digitized shape ...)

# make GeoJSON polygon from (last) digitized polygon feature
polyft = Map.draw_last_feature
from geojson import Polygon
coords = polyft.getInfo()['geometry']['coordinates']
poly = Polygon(coords) # coords[0] is the digitized polygon, [1] etc. would be holes
args["polygon"] = poly # use this GeoJSON polygon in processing
print("Using digitized polygon with", len(coords[0]), "points")


## Processing¶

• Running the cell below processes the data and creates a zip file with the model file(s) inside. This zip file will be inside the tmp folder (which is inside the same folder your notebook file is in).
• This may take some time!
• During processing you'll see a star indicator (In[*]) and some log messages. (Those messages will also be in the logfile inside the zip)
• You may see some red messages with 10%, etc. - don't worry, that's normal
In [ ]:
totalsize, full_zip_file_name = TouchTerrain.get_zipped_tiles(**args) # args are in a dict
print("\nDONE!\n\nCreated zip file", full_zip_file_name,  "%.2f" % totalsize, "Mb")

In [ ]:
# If you want to unzip the zip file, run this cell
# (You will need to do this before using k3d for visualization)

import os.path
from glob import glob
folder, file = os.path.splitext(full_zip_file_name) # get folder of zip file

# unzip the zipfile into the folder it's already in
import zipfile
zip_ref = zipfile.ZipFile(full_zip_file_name, 'r')
zip_ref.extractall(folder)
zip_ref.close()
print ("unzipped files from", full_zip_file_name, "into the folder", folder)
print (folder, "contains these files:")
for f in glob(folder + os.sep + "*.*"): print(" ", f)


## Visualize the STL file(s)¶

• If you want to visualize your model(s), install k3d (pip install k3d) and run the cell below
• this won't work with OBJ files, as k3d can't read them in.
• binary STL should work, but ascii may not.
In [ ]:
import k3d
from glob import glob

# get all stl files (tiles) in that folder
mesh_files = glob(folder + os.sep + "*.STL")

plot = k3d.plot()

# Add all tiles with a random color
from random import randint
for m in mesh_files:
col = (randint(0,255) << 16) + (randint(0,255) << 8) + randint(0,255) # random rgb color as hex

# If you plan to refine your parameters and create different models, you should run this cell to remove