[Bf-python] Latest update on Mesh module

Campbell Barton cbarton at metavr.com
Mon Oct 17 23:59:24 CEST 2005

Ken, brief reply...
There are cases where you would want to transform a mesh (as well as the 
blender mesh) - I can think of a few cases Im alredy doing this- 
Advanced array with skinning. and vertex displacement script, that 
applys the objects matrix. Through without a copy function I can see 
your right.

However a getRawFromObject would get the mesh data unlinked to the 
original mesh, so transforming it would be fine.

it would be realy nice to do somthing like Mathutils and have a copymesh 
newMesh = Blender.Mesh.New(existingMesh) # could be different syntax.
I was thinking of how Mathutils copys matrix/vector by "vec = 

Scanfill is Shift+F in edit mode with an edge loop selected.
Recalc normals is Ctrl+N, hope that covers it, maybe I missed somthing.

- Cam

Ken Hughes wrote:
> Campbell Barton wrote:
>> Ken Hughes wrote:
>>> So I'm looking now at the other miscellaneous methods in NMesh, with 
>>> future thoughts of replacing NMesh completely.  Should I recode all 
>>> of those methods, or are there some "legacy" ones which don't make 
>>> much sense anymore or are rarely used?  Are they any methods 
>>> glaringly missing, based on recent additions elsewhere in Blender.
>> Hi Ken, I use nmesh.transform(matrix) a lot for exporters, should be 
>> trivial, and could use the same syntax as  NMesh.
>> An equivilent to NMesh.getRawFromObject is needed for exporters 
>> (maybe there could be added a function like Alt+C, then you get the 
>> resulting mesh)
> I think the two points above are separate, so I'll discuss separately 
> first.
> I don't know if a mesh.transform() is a good idea in the thin mesh 
> case, since it's going to change all the mesh's vertices.  It's not 
> like NMesh where (as I understand it) you can do nmesh.transform() and 
> as long as you don't do nmesh.update() the original mesh remains 
> unchanged.  An alternative might be to have the method return a 
> sequence of transformed vertices and assign to mesh.verts:
> origverts = mesh.verts[:]
> mesh.verts = mesh.transform()
> # do export stuff with transformed verts
> mesh.verts = origverts
> I'll look into coding a version of getRawFromObject(); had forgot 
> about that method completely.
> Combining the two points above, another way to approach 
> mesh.transform() is to copy the mesh and transform it, leaving the 
> original alone.
>> Another usefull function is scanfill. though this will probably be a 
>> editmode only function too.
>> I have also needed a "Recalc Normals Outside" function, with some 
>> mesh generation its tricky to work out wich way to flip the face,
> Are there scanfill and "recalc normals" tools already somewhere in 
> blender?  Not only do I want to avoid reinventing the wheel, if the 
> code isn't already in Blender itself them maybe it should be?
>> I was wondering if the editMode functions work when there are no ed 
>> views open?
> Well, if you call mesh.subdivide() and have marked the edges you want 
> to subdivide (either in the UI or by selecting their vertices in 
> BPython) it works.  It does so by using the editmesh structure, which 
> is why you can't have an edit view open.  Specifically, I set G.obedit 
> to an object linked to the current mesh.  Elsewhere in the editmesh 
> code it relies on G.editMesh to point at the edit mesh structures 
> (which, from what I can see, always points to the static variable 
> theEditMesh).  I haven't looked into creating my own copy of the edit 
> mesh structures and pointing G.editMesh at that as well... if others 
> think "you can't be in edit mode" is too much of a constraint I'll 
> look into it.
> Ken
> _______________________________________________
> Bf-python mailing list
> Bf-python at projects.blender.org
> http://projects.blender.org/mailman/listinfo/bf-python

Campbell J Barton

133 Hope Street
Geelong West, Victoria 3218 Australia

URL:    http://www.metavr.com
e-mail: cbarton at metavr.com
phone: AU (03) 5229 0241

More information about the Bf-python mailing list