Turn Digital Terrain Models (DTMs) to STL files (TIFFs from Astropedia)
Download a DEM image of choice from Astropedia (or elsewhere), for example this DEM from Mars' moon Phobos:
From the metadata/PDS label configure the following setups (coverage, conversion, data type, etc.):
# User Preferences
FileName = "Phobos" # name of output STL file (DO NOT include .stl extension)
poleSquare = bool(0) # boolean for whether source image is a "polar square" or normal "equi-rectangular", 1(T) or 0(F)
normalize = bool(1) # boolean to select whether or not to normalize the units to max(max()) dimension, 1(T) or 0(F)
plotShow = bool(0) # show surface plot (1/T) or not (0/F)
OutCSV = bool(0) # output pixel data to csv (1/T) or not (0/F)
# Base Body/Model Parameters
R0 = 11100 # base 'radius' of parent body (m)
LatRange = [90, -90] # range of latitudes (°) Top to Bottom
LongRange = [-180, 180] # range of longitudes (°) Left to Right
def radiusFunc(DN): # Data Number (DN) to Radius Function (change as needed)
radius = DN + R0
return radius
if (poleSquare):
arc = 30 # angular width of "pole square" data (2x latitude range, °)
# Load Image of DTM (change array data type as needed)
DTM = Image.open(dirname + "\Image_Filename.tif")
DTM_Array = np.array(DTM,'int16') # make sure the data type is correct
The script creates a UTF-8 encoded STL from the data. Here is the STL output for the Phobos DEM:
The "ridges" are an artifact from the data, not the script.
Here is another example of the Lunar south pole (1/32 resolution, 75° S):
You can use the attached TIFF_Reduction.m MATLAB script to reduce very large TIFFs (~GBs) to more manageable sizes. This was done for the above Lunar maps.