Export 3D objects to Wavefront .obj format

Maybe this helps

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There is also this tutorial :
https://gmic.eu/bouncing_balls3d/

I want to try out this elevation 3d with vents generated by Inkscape dotted-line text outset … (dots which allow vacuum-air to pass through and increase chocolate mold precision:).
image

Example from industrial design course slides:

The big block disc at the top left corner is also a way to ensure that a hole is created… assuming that possibly black = no volume (or … my question is how to control elevation3d so that a color provides no volume == is a hole).
svg and png counterparts below
lithophane_with_vents

I have got a crash with the latter png:
image

Python 3.7.5 (default, Apr 19 2020, 20:18:17) 
[GCC 9.2.1 20191008] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import gmic
gmic-py: If you do not see any text for G'MIC 'print' or 'display' commands, you could '!pip install wurlitzer' and if under an IPython environment, run the '%load_ext wurlitzer' macro. See https://github.com/myselfhimself/gmic-py/issues/64
>>> gmic.run("/home/jd/Productions/GMIC/lithophane/lithophane_with_vents.png elevation3d -0.02,10 display")
[gmic]-1./ Display image [0] = '('CImg3d':y)', from point (0,266742244,0).
[0] = '('CImg3d':y)':
  size = (1,533484488,1,1) [2035 Mio of floats].
  data = (67.5;73.5;109.5;103.5;51.5;100.5;-83.1803;-83.1803;0;0;-0;1;(...),1;1;1;1;1;1;1;1;1;1;1;1).
  min = -83.1803, max = 524287, mean = 1478.6, std = 18961.3, coords_min = (0,6,0,0), coords_max = (0,135959176,0,0).
Killed

(the Killed is not my killing, but G’MIC + Python crashing altogether)

Trying at 500dpi instead of 1000dpi, and using display3d instead of display, I see nothing:



My computer is very slow at displaying something.

Is there a color for 0 elevation or hole?.. I would like the black color to be boolean substracted somehow…

Hello Jonathan,

Note that elevation3d always produces a 3d object that has at least W\times H vertices and as many quadrangles (and the double if you activate the base feature).
So, for an image 6595\times 3370 , it means at least 22,225,150 vertices which is actually a quite big object (particularly if you want to output this as an .obj file, which is ascii-encoded by nature). This would lead to a huge output file
(I don’t even think Blender could reasonnably re-import it, considering that its Wavefront import module is not really optimized).

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For stuff like that, CAD is often more reasonable than using gmic. I’m sure basic CAD is enough.

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I will publish something this year on filament 3d printing slicing parameters which makes a 3d print porous and spares oneself to do any vents on the CAD side. This is an intrinsic property of filament 3d prints, which can be exaggerated in the perspective of thermoforming for chocolate molds-making etc…