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I have an object located in the origin (0,0,0). I wonder how I can translate it along the z-axis where the lowest -z value of the object will be translated to z value 0 as shown below:

enter image description here

Tak
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  • Loop over the vertices, find the one with the lowest z value, move the object up -whatever_the_previous_got_you :-) I'll post an answer in a few... – JakeD Feb 15 '17 at 12:42
  • related http://blender.stackexchange.com/a/42110/15543 in that it moves the origin to bottom. – batFINGER Feb 15 '17 at 14:21

1 Answers1

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Here is a simple script that accomplishes this...let me know if you have any questions.

import bpy

# get a reference to the active object
obj = bpy.context.object

# get the minimum z-value of all vertices after converting to global transform
lowest_pt = min([(obj.matrix_world * v.co).z for v in obj.data.vertices])

# transform the object
obj.location.z -= lowest_pt

Note

For 2.8 replace * with @ for matrix multiplication.

lowest_pt = min([(obj.matrix_world @ v.co).z for v in obj.data.vertices])
batFINGER
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JakeD
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    Can also find the lowestZ in one line instead of a loop thus: lowestZ = min( [ ( obj.matrix_world * v.co ).z for v in obj.data.vertices ] ) – TLousky Feb 15 '17 at 13:04
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    Adding object location to local vert coordinate is not converting to global location. See comment above. – batFINGER Feb 15 '17 at 14:25
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    @TLousky Thanks! Your method also works correctly with rotation and scale that I wasn't thinking about when I posted originally. I have edited my answer to include this technique... – JakeD Feb 15 '17 at 14:50
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    @batFINGER I was fooled into thinking this b/c I was not using a rotated or scaled object. – JakeD Feb 15 '17 at 14:50
  • @pycoder what if the object was an armature? It doesn't work in that case as this solution only works for mesh as it uses the mesh vertices – Tak Mar 05 '17 at 02:49
  • @Tak That's a completely different problem, and something that I can't really think of a good reason to need off the top of my head. Would you be calculating based on the center of bones? The heads and tails? I think this would be better suited for a different question that explains these things clearly and gives an example of when you may want to use it. – JakeD Mar 05 '17 at 03:18
  • @pycoder http://blender.stackexchange.com/questions/74936/move-object-without-changing-origin – Tak Mar 05 '17 at 03:20
  • The line 7 doesn't work in Blender 2.8: TypeError: Element-wise multiplication: not supported between 'Matrix' and 'Vector' types

    What should we write instead? Thank you.

     – Danyl Bekhoucha Jan 11 '19 at 18:51
  • @DanylBekhoucha You should ask that as a separate question if you need an answer. I've not looked into porting my add-ons to Blender 2.8 yet, so I don't know off the top of my head. – JakeD Jan 11 '19 at 22:27