Hello,

I'm looking for how to rotate an object coordinate system so that a chosen axis (from the object coordinate system) is normal to an object face.

Thanks in advance for your help.

## Rotate object coordinate system

**Moderators:** jesterKing, stiv

maybe this helps:

http://wiki.blender.org/index.php/Exten ... cise_Align

otherwise, it's possible to write a python addon to do so, i'm just a little unsure about normal vector to rotation matrix conversion (rather math problem)

http://wiki.blender.org/index.php/Exten ... cise_Align

otherwise, it's possible to write a python addon to do so, i'm just a little unsure about normal vector to rotation matrix conversion (rather math problem)

I'm sitting, waiting, wishing, building Blender in superstition...

i'm stuck at the required math, basically rotation matrix construction :/

however, i know how to do the rest

rough outline:

this might be relevant for the mat construction:

http://www.gamedev.net/topic/602485-dir ... on-matrix/

however, i know how to do the rest

rough outline:

Code: Select all

```
active_ob = bpy.context.active_object
sel_obs = bpy.context.selected_objects
sel_obs.remove(active_ob)
me = active_ob.data
face_normal = me.polygons[me.polygons.active].normal
# construct rotation matrix
for ob in sel_obs:
ob.matrix_world *= rot_mat
```

http://www.gamedev.net/topic/602485-dir ... on-matrix/

I'm sitting, waiting, wishing, building Blender in superstition...