Blender 3D: Blending Into Python/Cookbook

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Image Functions[edit | edit source]

Edit Image in External Program[edit | edit source]

This runs in linux (probably any unix), and launches The Gimp. It could probably be modified to launch Photoshop in windows.
In Gnome, KDE and Mac OS X, you can use a command to open documents using the default or a specified application.

  • KDE: kfmclient openURL <URL, relative or absolute path>
  • Gnome: gnome-open <any URL or path Gnome understands>
  • Mac OS X: open [-a <application name>] <path>

Win32 has some open command too, maybe somebody could add this in.

Name: 'Edit Image in the Gimp'
Blender: 232
Group: 'UV'
Tooltip: 'Edit Image in the Gimp.'
from Blender import *
import os

def main():
	image = Image.GetCurrent()
	if not image: # Image is None
		print 'ERROR: You must select an active Image.'
	imageFileName = sys.expandpath( image.filename )
	#appstring = 'xnview "%f"'
	#appstring = 'gqview "%f"'
	appstring = 'gimp-remote "%f"'
	# -------------------------------
	appstring = appstring.replace('%f', imageFileName)

if __name__ == '__main__':

Find Images[edit | edit source]

This script recursively searches for images that have broken files references.
It works by giving the user a root path, then finds and re-links all images within that path.
Its very useful when migrating projects to different computers.

Name: 'Find all image files'
Blender: 232
Group: 'UV'
Tooltip: 'Finds all image files from this blend an relinks'

__author__ = "Campbell Barton AKA Ideasman"
__url__ = ["", "blender", "elysiun"]

__bpydoc__ = """\

from Blender import *
import os

# Strips the slashes from the back of a string #
def stripPath(path):
	return path.split('/')[-1].split('\\')[-1]

# finds the file starting at the root.
def findImage(findRoot, imagePath):
	newImageFile = None
	imageFile = imagePath.split('/')[-1].split('\\')[-1]
	pathWalk = os.walk(findRoot)
	pathList = [True]
	matchList = [] # Store a list of (match, size), choose the biggest.
	while True:
			pathList  =
		for file in pathList[2]:
			if file.lower() == imageFile.lower():
				name = pathList[0] + sys.sep + file
					size = os.path.getsize(name)
					size = 0
				if size:
					print '   found:', name 
					matchList.append( (name, size) )
	if matchList == []:
		print 'no match for:', imageFile
		return None
		# Sort by file size
		matchList.sort(key=lambda x: x[1], reverse=True )
		print 'using:', matchList[0][0]
		# First item is the largest
		return matchList[0][0] # 0 - first, 0 - pathname

# Makes the pathe relative to the blend file path.
def makeRelative(path):
	blendBasePath = sys.expandpath('//')
	if path.startswith(blendBasePath):
		path = path.replace(blendBasePath, '//')
		path = path.replace('//\\', '//')
	return path

def find_images(findRoot):
	print findRoot
	# findRoot = Draw.PupStrInput ('find in: ', '', 100)
	if findRoot == '':
		Draw.PupMenu('No Directory Selected')
	# Account for //
	findRoot = sys.expandpath(findRoot)
	# Strip filename
	while findRoot[-1] != '/' and findRoot[-1] != '\\':
		findRoot = findRoot[:-1]
	if not findRoot.endswith(sys.sep):
		findRoot += sys.sep
	if findRoot != '/' and not sys.exists(findRoot[:-1]):
		Draw.PupMenu('Directory Dosent Exist')
	# ============ DIR DONE\
	images = Image.Get()
	len_images = float(len(images))
	for idx, i in enumerate(images):

		progress = idx / len_images
		Window.DrawProgressBar(progress, 'searching for images')
		# If files not there?
		if not sys.exists(sys.expandpath(i.filename )):	
			newImageFile = findImage(findRoot, i.filename)
			if newImageFile != None:
				newImageFile = makeRelative(newImageFile)
				print 'newpath:', newImageFile
				i.filename = newImageFile
	Window.DrawProgressBar(1.0, '')

if __name__ == '__main__':
	Window.FileSelector(find_images, 'SEARCH ROOT DIR', sys.expandpath('//'))

Remove Double Images[edit | edit source]

This script finds images that are referenced more than once, and looks through all meshes texface's, and assigns only one of the images.
If a face has no users the image is removed.
This is useful because when an image is loaded more than once, it's also loaded into system memory and graphics card memory more than once, wasting resources.
Support for image type textures still needs doing.

Name: 'Remove Double Images' 
Blender: 232 
Group: 'UV' 
Tooltip: 'Remove Double Images'

from Blender import *

def main():
	# Sync both lists 
	fNameList = []# 
	bImageList = [] # Sync with the one abovr.
	bImageReplacePointer = dict() # The length of IMage.Get()
	imgIdx = 0
	# Sort by name lengths so image.001 will be replaced by image
	Images = Image.Get()
	Images.sort(key=lambda x: len(, reverse=True )
	for bimg in Images:
		expendedFName = sys.expandpath(bimg.filename)
		bImageReplacePointer[expendedFName] = bimg
	print 'Remove Double Images, loading mesh data...',
	uniqueMeshNames = []
	# get all meshs
	doubles = 0
	for ob in Object.Get():
		if ob.getType() == 'Mesh' and ob.getData(1) not in uniqueMeshNames:
			m = ob.getData(mesh=1)
			# We Have a new mesh,
			imageReplaced = 0
			for f in m.faces:
				image = None
				try: image = f.image
				except: pass
				if image:
					replaceImage = bImageReplacePointer[ sys.expandpath(f.image.filename) ]
					if !=
						f.image = replaceImage
						imageReplaced = 1
			if imageReplaced:
				doubles += 1
				print '\tchanged',
				print '\tunchanged',
	print 'Done, %i doubles removed.' % doubles

if __name__ == '__main__':

Material Functions[edit | edit source]

Toon Material Batch Conversion Script[edit | edit source]

this script changes *all* materials in your currently open blend file to toon materials. after executing, check the blender console for script output.

as this script alters *all* of your material settings in your currently opened blend file, you should *not* run it on a project that has not been saved yet! changes made to materials while using this script cannot be undone!

note: changes are not permanently committed to your blend file unless you choose to save your file after executing this script.

import Blender

from Blender import Material, Scene
from Blender.Scene import Render


# Get list of active materials from Blender
materials = Blender.Material.Get()

# Get render information needed for edge setting
scn = Scene.GetCurrent()
context = scn.getRenderingContext()


# Change materials to Toon Diffuse/Specular
for m in materials:

   # Diffuse Shader (2 = Toon)
   # Specular Shader (3 = Toon)


   # Diffuse Size (0 to 3.14)

   # Diffuse Smooth (0 to 1.0)

   # Reflect Amount (0 to 1.0)
   # - optionally here to help you
   # with any necessary batch changes
   # to all material reflection values
   # Remove "#" from line below to use:
   # m.setRef(.75)

   # Specular (0 to 2.0)

   # Specular Smooth (0 to 1.0)

   # Specular Size (0 to 3.14)

   # Enable toon edge: 0 = off, 1 = on

   # Edge Intension (0 to 255)



Curve Functions[edit | edit source]

Length of a curve[edit | edit source]

This function gets the combined length of all edges. Most useful to get the length of a curve. Be careful, because it will get the length of every curve in a curve object!

Note that this function doesn't take the object's transformation into account when getting the length.

from Blender import Mesh, Object
def curve_length(ob): # Can realy be any object
    me= Mesh.New()
    totlength= 0.0
    for ed in me.edges:
        # Blender 2.42 can simply do
        # totlength+= ed.length
        totlength+= (
    return totlength

cu_ob= Object.Get('mycurve')
print curve_length(cu_ob)

Text Functions[edit | edit source]

Paste Text in Unix[edit | edit source]

Paste text in X11, requires uclip [[1]]

Name: 'Text from Clipboard'
Blender: 234
Group: 'Add'
Tooltip: 'Text from Clipboard X11'
from Blender import Text
import os

clip = os.popen('uclip -o')

clipTxt =
text = Text.New(clipTxt[0:10])

Save all Texts as files[edit | edit source]

Saves all text editor texts as files in the current working directory. WARNING: This will overwrite files with those names!

import Blender


for text in texts:
        out=file(, 'w')
        for line in text.asLines():

Mesh Functions[edit | edit source]

Examples and functions for Blenders NMesh, GMesh and new Mesh module.

Mesh tool template[edit | edit source]

Use this to base your editmode mesh tool on.

""" Registration info for Blender menus:
Name: 'Template Mesh Editmode tool...'
Blender: 237
Group: 'Mesh'
Tooltip: 'Change this template text tooltip'

__author__ = "Your Name"
__url__ = ("blender", "elysiun")
__version__ = "1.0"

__bpydoc__ = """\
Multilin Script Help
Document your script here.

from Blender import *

def main():
	scn = Scene.GetCurrent()
	ob = scn.getActiveObject() # Gets the current active object (If Any)
	if ob == None or ob.getType() != 'Mesh': # Checks the active objects a mesh
		Draw.PupMenu('ERROR%t|Select a mesh object.')
	Window.WaitCursor(1) # So the user knowns the script is busy.
	is_editmode = Window.EditMode() # Store edit mode state
	if is_editmode: Window.EditMode(0) # Python must get a mesh in object mode.
	me = ob.getData()
	for v in me.verts:
		if v.sel: # Operating on selected verts is what the user expects. = * 2
	me.update() # Writes the mesh back into Blender.
	# Go back into editmode if we started in edit mode.
	if is_editmode: Window.EditMode(1)

if __name__ == '__main__': # Dont run the script if its imported by another script.

Desaturate Meshes VertCol[edit | edit source]

Uses the new Mesh module. In Blender 2.4 only. Desaturates using the same weighting as Photoshop uses.

from Blender import Mesh, Object
for ob in Object.GetSelected():
        if ob.getType() == 'Mesh':
                me = ob.getData(mesh=1)
                if me.faceUV:
                        for f in me.faces:
                                for c in f.col:
                                        # Weighted colour conversion, as used by photoshop.
                                        c.r = c.g = c.b = int(((c.r*30) + (c.g*59) + (c.b*11)) / 100.0)

Point inside a Mesh[edit | edit source]

This function returns 1/0 depending on whether the provided point is inside a mesh. It relies on the mesh having a continuous skin, no holes in it. (Otherwise the problem doesn't make sense.)

It uses the method of seeing how many face intersections there are along a line segment between that point, and a point somewhere outside the meshs bounds.

An even number of intersections means it's outside, an odd for inside. Hence we return len(intersections) % 2 where intersections generates a list of intersections.

This function uses a Z direction vector so we can save some CPU cycles by first doing an X/Y bounds test to see if the points could intersect, before doing a full ray intersection.

from Blender import *

def pointInsideMesh(ob, pt):
	Intersect = Mathutils.Intersect # 2 less dict lookups.
	Vector = Mathutils.Vector
	def ptInFaceXYBounds(f, pt):
		co= f.v[0].co
		xmax= xmin= co.x
		ymax= ymin= co.y
		co= f.v[1].co
		xmax= max(xmax, co.x)
		xmin= min(xmin, co.x)
		ymax= max(ymax, co.y)
		ymin= min(ymin, co.y)
		co= f.v[2].co
		xmax= max(xmax, co.x)
		xmin= min(xmin, co.x)
		ymax= max(ymax, co.y)
		ymin= min(ymin, co.y)
		if len(f.v)==4: 
			co= f.v[3].co
			xmax= max(xmax, co.x)
			xmin= min(xmin, co.x)
			ymax= max(ymax, co.y)
			ymin= min(ymin, co.y)
		# Now we have the bounds, see if the point is in it.
		return xmin <= pt.x <= xmax and \
			ymin <= pt.y <= ymax
	def faceIntersect(f):
		isect = Intersect(f.v[0].co, f.v[1].co, f.v[2].co, ray, obSpacePt, 1) # Clipped.
		if not isect and len(f.v) == 4:
			isect = Intersect(f.v[0].co, f.v[2].co, f.v[3].co, ray, obSpacePt, 1) # Clipped.
		return bool(isect and isect.z > obSpacePt.z) # This is so the ray only counts if its above the point. 
	obImvMat = Mathutils.Matrix(ob.matrixWorld)
	obSpacePt = pt* obImvMat
	ray = Vector(0,0,-1)
	me= ob.getData(mesh=1)
	# Here we find the number on intersecting faces, return true if an odd number (inside), false (outside) if its true.
	return len([None for f in me.faces if ptInFaceXYBounds(f, obSpacePt) if faceIntersect(f)]) % 2

# Example, see if the cursor is inside the mesh.
if __name__ == '__main__':
	scn= Scene.GetCurrent()
	ob= scn.getActiveObject()
	pt= Mathutils.Vector(Window.GetCursorPos())
	print 'Testing if cursor is inside the mesh',
	inside= pointInsideMesh(ob, pt)
	print inside

Scanfill for importers[edit | edit source]

This function takes a mesh and a list of vert indicies representing an ngon. It returns a list of tri indicies that make up the scanfilled face. This is much more useful for importers.

it also handles cases where scanfill does not work by returning a triangle fan.

It may be faster then using the mesh.fill() function on your original mesh because cycling editmode can be slow on a lot of data. Another advantage with this function over simply using fill() is you can be sure the faces will be flipped the right way, according to the order of the indicies.

from Blender import *
def ngon(from_mesh, indicies):
	if len(indicies) < 4:
		return [indicies]
	is_editmode= Window.EditMode()
	if is_editmode:
	temp_mesh = Mesh.New()
	temp_mesh.verts.extend( [from_mesh.verts[i].co for i in indicies] )
	temp_mesh.edges.extend( [(temp_mesh.verts[i], temp_mesh.verts[i-1]) for i in xrange(len(temp_mesh.verts))] )
	oldmode = Mesh.Mode()
	for v in temp_mesh.verts:
		v.sel= 1
	# Must link to scene
	scn= Scene.GetCurrent()
	temp_ob= Object.New('Mesh')
	new_indicies= [ [v.index for v in f.v]  for f in temp_mesh.faces ]
	if not new_indicies: # JUST DO A FAN, Cant Scanfill
		print 'Warning Cannot scanfill!- Fallback on a triangle fan.'
		new_indicies = [ [indicies[0], indicies[i-1], indicies[i]] for i in xrange(2, len(indicies)) ]
		# Use real scanfill.
		# See if its flipped the wrong way.
		flip= None
		for fi in new_indicies:
			if flip != None:
			for i, vi in enumerate(fi):
				if vi==0 and fi[i-1]==1:
					flip= 0
				elif vi==1 and fi[i-1]==0:
					flip= 1
		if flip:
			for fi in new_indicies:
	if is_editmode:
	return new_indicies

# === ===== EG
scn= Scene.GetCurrent()
me = scn.getActiveObject().getData(mesh=1)
ind= [v.index for v in me.verts if v.sel] # Get indicies

indicies = ngon(me, ind) # fill the ngon.

# Extand the faces to show what the scanfill looked like.
print len(indicies)
me.faces.extend([[me.verts[ii] for ii in i] for i in indicies])

Triangulate NMesh[edit | edit source]

This is a function to be used by other scripts, its useful if you want to make your life simpler by only dealing with triangles.
The shortest edge method is used for dividing the quad into 2 tri's.

def triangulateNMesh(nm):
	Converts the meshes faces to tris, modifies the mesh in place.
	# Returns a new face that has the same properties as the origional face      #
	# but with no verts                                                          #
	def copyFace(face):
		newFace = NMesh.Face()
		# Copy some generic properties
		newFace.mode = face.mode
		if face.image != None:
			newFace.image = face.image
		newFace.flag = face.flag
		newFace.mat = face.mat
		newFace.smooth = face.smooth
		return newFace
	# 2 List comprehensions are a lot faster then 1 for loop.
	tris = [f for f in nm.faces if len(f) == 3]
	quads = [f for f in nm.faces if len(f) == 4]
	if quads: # Mesh may have no quads.
		has_uv = quads[0].uv 
		has_vcol = quads[0].col
		for quadFace in quads:
			# Triangulate along the shortest edge
			if (quadFace.v[0].co - quadFace.v[2].co).length < (quadFace.v[1].co - quadFace.v[3].co).length:
				# Method 1
				triA = 0,1,2
				triB = 0,2,3
				# Method 2
				triA = 0,1,3
				triB = 1,2,3
			for tri1, tri2, tri3 in (triA, triB):
				newFace = copyFace(quadFace)
				newFace.v = [quadFace.v[tri1], quadFace.v[tri2], quadFace.v[tri3]]
				if has_uv: newFace.uv = [quadFace.uv[tri1], quadFace.uv[tri2], quadFace.uv[tri3]]
				if has_vcol: newFace.col = [quadFace.col[tri1], quadFace.col[tri2], quadFace.col[tri3]]
				nm.addEdge(quadFace.v[tri1], quadFace.v[tri3]) # Add an edge where the 2 tris are devided.
		nm.faces = tris

Fix vertex winding in "bowtie" quads[edit | edit source]

Sometimes you may encounter quad faces which, although correctly coplanar, aren't quite "full". This comes from the vertices being in the wrong order, and causes the face to overlap itself, often leaving undesired holes and black areas where the normals point the wrong way. To see what this all means, just make a plane and switch places for the vertices at any edge. The connecting edges will then cross. Since the normals of the face don't make sense in this situation, the script can't guarantee that the normal points outwards after finishing.

Name: 'Quadsorter'
Blender: 233
Group: 'Mesh'
Tip: 'Fix winding order for quad faces for all selected meshes'
Author: Yann Vernier (LoneTech)

from Blender.Mathutils import Vector, CrossVecs, DotVecs

def sortface(f):
  if len(f) != 4:
    return f
  v=[Vector(list(p)) for p in f]
  # The normal of the plane
  n=CrossVecs(v[1]-v[0], v2m0)
  #if DotVecs(v[3],n) != k:
  #  raise ValueError("Not Coplanar")
  # Well, the above test would be a good hint to make triangles.
  # Get a vector pointing along the plane perpendicular to v[0]-v[2]
  n2=CrossVecs(n, v2m0)
  # Get the respective distances along that line
  k=[DotVecs(p,n2) for p in v[1:]]
  # Check if the vertices are on the proper side
  if cmp(k[1],k[0]) == cmp(k[1],k[2]):
    #print "Bad",v

from Blender.Object import GetSelected
for obj in GetSelected():
  if obj.getType() == 'Mesh':
    for face in mesh.faces:

Remove Verts Without removing entire faces[edit | edit source]

Script that uses the mesh template above. removes verts but surrounding quads will be converted to tri's.
Note This only works with NMesh.

        # EDIT MESH HERE #
        for f in me.faces:
            face_verts = f.v[:] # make a copy of the list.
            for v in face_verts:
                if v.sel:
        # Remove all with less then 3 verts,
        # When removing objects from a list its best to loop backwards
        fIdx = len(me.faces)
        while fIdx:
            fIdx -=1
            f = me.faces[fIdx]
            if len(f.v) < 3:
                del me.faces[fIdx]
        # Remove all selected verts
        # Loop backwards.
        vIdx = len(me.verts)
        while vIdx:
            vIdx -=1
            v = me.verts[vIdx]
            if v.sel:
                del me.verts[vIdx]
        # FINISH EDITING #

GMesh AutoSmooth Mesh[edit | edit source]

This function uses GMesh to autosmooth manifold meshes, it requires the GMesh module.

Be careful because it will smooth your mesh in place, so make a copy of your original object if you don't want it modified.

from Blender import *
import GMesh

smooth = Draw.PupIntInput('smooth:', 20,1,89)

for ob in Object.GetSelected():
        mesh = ob.getData()
        gmesh = GMesh.NMesh2GMesh(mesh)

                print 'Error non manifold mesh'
                continue # go onto the next item

        mesh = GMesh.GMesh2NMesh(gmesh)

        # Make the faces smooth
        for f in mesh.faces:
                f.smooth = 1 # Link the new mesh with the original object

ScanFill[edit | edit source]

To simulate typing "Shift F" in blender to create scanfill selected edge loop (edit mode only)

This will only work if the 3D view is open.

import Blender

winid = Blender.Window.GetScreenInfo(Blender.Window.Types.VIEW3D)[0]['id']
Blender.Window.QAdd(winid, Blender.Draw.FKEY,1)

Expanded Scanfill function[edit | edit source]

Self contained scanfill function, based on the code above. Note, this function needs a 3D view to be available

import Blender

# Take a list of points and return a scanfilled NMesh
def scanFillPoints(pointList):

        nme = Blender.NMesh.New()
        # 2.37 compatability, not needed in 2.4
        if not nme.edges:

        for p in pointList:
                v = Blender.NMesh.Vert( p[0], p[1], p[2] )
                v.sel = 1

                if len(nme.verts) >= 2:
                        nme.addEdge(nme.verts[-2], nme.verts[-1])

        nme.addEdge(nme.verts[0], nme.verts[-1])

        scn = Blender.Scene.GetCurrent()

        actOb = scn.getActiveObject()
        if actOb:
                actSel = actOb.sel
                actSel = 0

        ob = Blender.Object.New('Mesh')
        scn.layers = range(1,20)
        ob.sel = 1

        winid = Blender.Window.GetScreenInfo(Blender.Window.Types.VIEW3D)[0]['id']
        Blender.Window.QAdd(winid, Blender.Draw.FKEY,1)

        # scn.unlink(ob)

        # Select the old active object.
        if actOb:
                actOb.sel = actSel

        # Reture the scanfilled faces.
        return ob.getData()

Example function usage.

scanFillPoints([[-1,-1,0], [1,-1,1], [1,1,0], [0,0,0.2], [0,1,-.1], [0.1,1,-0.3] ])

Copy NMesh Face[edit | edit source]

Returns a new face that has the same properties as the original face but with no verts

def faceCopy(face):
  newFace = NMesh.Face()
  # Copy some generic properties
  newFace.mode = face.mode
  if face.image != None:
    newFace.image = face.image
  newFace.flag = face.flag
  newFace.mat = face.mat
  newFace.smooth = face.smooth
  return newFace

Returns the Faces centre as a Vector[edit | edit source]

Note, Blenders Mesh API now has face.cent access

Take 1 NMFace and return a vector as its centre, will use an existing vector object "cent" if provided.

def faceCent(f, cent=None):
	x = y = z = 0
	for v in f.v:[0][1][2]
	if not cent:
		return Mathutils.Vector([x/len(f.v), y/len(f.v), z/len(f.v)])
	# Modify the provided vec
	cent.x = x/len(f.v)
	cent.y = y/len(f.v)
	cent.z = z/len(f.v)

Flip Faces Up[edit | edit source]

I used this script to flip all faces in many terrain meshes to point up. It uses Mesh as opposed to NMesh.

from Blender import *

# Apply Tpransform #
#==================# Used for skin
def apply_transform(vec, matrix):
        x, y, z = vec
        xloc, yloc, zloc = matrix[3][0], matrix[3][1], matrix[3][2]
        vec.x = x*matrix[0][0] + y*matrix[1][0] + z*matrix[2][0] + xloc
        vec.y = x*matrix[0][1] + y*matrix[1][1] + z*matrix[2][1] + yloc
        vec.z = x*matrix[0][2] + y*matrix[1][2] + z*matrix[2][2] + zloc

def apply_transform3x3(vec, matrix):
        x, y, z = vec
        vec.x = x*matrix[0][0] + y*matrix[1][0] + z*matrix[2][0]
        vec.y = x*matrix[0][1] + y*matrix[1][1] + z*matrix[2][1]
        vec.z = x*matrix[0][2] + y*matrix[1][2] + z*matrix[2][2]

# Point to z up.
noVec = Mathutils.Vector(0,0,-10000)
cent = Mathutils.Vector(0,0,0)

for ob in Object.GetSelected():
        if ob.getType() != 'Mesh':
        mat = ob.matrixWorld

        me = ob.getData(mesh=1)
        # We know were mesh

        # Select none
        for f in me.faces: f.sel = 0

        # Flip based on facing.
        for f in me.faces:
                no =
                apply_transform3x3(no, mat)
                # Get the faces centre
                cent.x, cent.y, cent.z = 0,0,0
                for v in f.v:
                        cent +=
                cent = cent * (1.0 / len(f.v))
                apply_transform(cent, mat)
                # Move the vec over the centre of the face.
                noVec.x = cent.x
                noVec.y = cent.y
                # Are we not facing up?, if not then select and flip later.
                if ((cent+no)-noVec).length <= (cent-noVec).length:
                        f.sel = 1

Scale UVs[edit | edit source]

Scales all uv coords for selected mesh objects.

from Blender import *
def main():
        # Scale the UV down.
        # This examples scales down by 1 pixel on a 512x512 image.
        shrink = 1-(1/512.0)

        for ob in Object.GetSelected():
                if ob.getType() == 'Mesh':
                        me = ob.getData(mesh=1)
                        if me.faceUV:
                                for f in me.faces:
                                        f.uv =\
                                        tuple([ Mathutils.Vector(\
                                         ) for uv in f.uv])

if __name__ == '__main__':

Find a material in all Meshes in all Scenes[edit | edit source]

Sometimes You have a lot of mesh object and materials you don't want any of them to use. This script can help you find those objects.

Name: 'Find Mesh with Material'
Blender: 234
Group: 'Object'
Tooltip: 'Find Mesh with Material'

from Blender import *

def main():
	matToFind = Draw.PupStrInput('matName:', '', 21)
	if matToFind == None:
	for scn in Scene.Get():
		for ob in scn.getChildren():
			if ob.getType() == 'Mesh':
				for mat in ob.getData(mesh=1).materials:
					matname = None
						matname =
						# Material must be None

					if matname == matToFind:
						# Unselect all in the scene
						for ob_ in scn.getChildren():
							ob_.sel = 0

						# Select the found object
						ob.sel = 1

						Draw.PupMenu('Material "%s" found in object "%s".' % (matToFind,

	Draw.PupMenu('Material "%s" Not found.' % matToFind)

if __name__ == '__main__':

Faces share an edge[edit | edit source]

The 2 faces share an edge, its best to make sure your not comparing the same faces, and remove the first 'if'.

# Do the 2 faces share an edge?
# return true or false.
def faceShareEdge(face1, face2):
	# Are we using the same verts. could be more comprehensive, since vert order may differ but still be the same.
	if face1.v == face2.v: 
		return False
	firstMatch = None
	for v1 in face1:
		if v1 in face2:
			if firstMatch is None:
				firstMatch = True
				return True
	return False

Get Edge Angles[edit | edit source]

Returns a list of angles, the combine angle difference of all faces that use the edges. the angles returned are in sync with mesh.edges. Edges with 0 or 1 faces will have Zero angle.

This function uses Blender.Mesh not Blender.NMesh mesh data.

def getEdgeAngles(me):
	Ang= Blender.Mathutils.AngleBetweenVecs
	Vector= Blender.Mathutils.Vector
	edges = dict( [ (ed.key,  (i, [])) for i, ed in enumerate(me.edges) ] )
	for f in me.faces:
		#print f.index
		for key in f.edge_keys:
	edgeAngles=[0.0] * len(me.edges)
	for eIdx, angles in edges.itervalues():
		angles_len= len(angles)
		if angles_len < 2:
		if angles_len==2:
			edgeAngles[eIdx] = Ang(angles[0], angles[1])
			for j in reversed(xrange(angles_len)):
				for k in reversed(xrange(j)):
					totAngDiff+= (Ang(angles[j], angles[k])/180) # /180 isnt needed, just to keeop the vert small.
			edgeAngles[eIdx] = totAngDiff
	return edgeAngles

Mesh Ray Intersect[edit | edit source]

Intersect a ray with a mesh, Assume the mesh has no loc/size/rot.

import Blender
from Blender import Window, Mathutils, Object
Vector= Mathutils.Vector
Intersect= Mathutils.Intersect
Matrix= Mathutils.Matrix

def meshRayIntersect(me, Origin, Direction):
	def faceIntersect(f):
		isect = Intersect(f.v[0].co, f.v[1].co, f.v[2].co, Direction, Origin, 1) # Clipped.
		if isect:
			return isect
		elif len(f.v) == 4:
			isect = Intersect(f.v[0].co, f.v[2].co, f.v[3].co, Direction, Origin, 1) # Clipped.
		return isect
	''' Ray is a tuple of vectors (Origin, Direction) '''
	isect= best_isect= None
	dist_from_orig= 1<<30
	for f in me.faces:
		isect= faceIntersect(f)
		if isect:
			l= (isect-Origin).length
			if l < dist_from_orig:
				dist_from_orig= l
				best_isect= isect
	return best_isect, dist_from_orig

Copy Vertex UV to Face UV[edit | edit source]

Copies the Vertex UV coordinates (Sticky) to face UV coordinates (TexFace).


""" Registration info for Blender menus:
Name: 'Vertex UV to face UV'
Blender: 241
Group: 'Mesh'
Tooltip: 'Copy vertex UV to face UV'
__author__ = "Brandano"
__url__ = ("blender", "elysiun")
__version__ = "1.0"
__bpydoc__ = """\
Copies the Vertex UV coordinates (Sticky) to face UV coordinates (TexFace).
Warning: the original face UV's will be overwritten.
import Blender
from Blender import Mesh

if (Blender.Object.GetSelected() != None):
    for me in [ob.getData(mesh=1) for ob in Blender.Object.GetSelected() if ob.getType() == "Mesh"]:
        if me.vertexUV:
            me.faceUV = 1
            for f in me.faces: f.uv = [v.uvco for v in f.verts]

Math Functions[edit | edit source]

Here is the place to add math examples, they can be blender specific or generic python math functions.

Changing Rotation Axis Order[edit | edit source]

If you ever have trouble converting between different rotation systems its possible that the order of rotations is the problem.

import Blender
RotationMatrix= Blender.Mathutils.RotationMatrix

MATRIX_IDENTITY_3x3 = Blender.Mathutils.Matrix([1.0,0.0,0.0],[0.0,1.0,0.0],[0.0,0.0,1.0])
def eulerRotateOrder(x,y,z): 
	x,y,z = x%360,y%360,z%360 # Clamp all values between 0 and 360, values outside this raise an error.
	xmat = RotationMatrix(x,3,'x')
	ymat = RotationMatrix(y,3,'y')
	zmat = RotationMatrix(z,3,'z')
	# Standard BVH multiplication order, apply the rotation in the order Z,X,Y
	# Change the order here
	return (ymat*(xmat * (zmat * MATRIX_IDENTITY_3x3))).toEuler()

Get Angle between 3 points[edit | edit source]

Get the angle between line AB and BC where b is the elbow.

import Blender
AngleBetweenVecs = Blender.Mathutils.AngleBetweenVecs

def getAng3pt3d(avec, bvec, cvec):
		ang = AngleBetweenVecs(avec - bvec,  cvec - bvec)
		if ang != ang:
			raise  "ERROR angle between Vecs"
			return ang
		print '\tAngleBetweenVecs failed, zero length?'
		return 0

Point inside a tri (2D)[edit | edit source]

Returns True if pt is inside the triangle.
only gives a correct answer when pt lies on the triangles plane.

from Blender import Mathutils
SMALL_NUM = 0.000001
def pointInTri2D(pt, tri1, tri2, tri3):
	a = Mathutils.TriangleArea(tri1, tri2, tri3)
	othera = Mathutils.TriangleArea(pt, tri1, tri2) + SMALL_NUM
	if othera > a: return False
	othera += Mathutils.TriangleArea(pt, tri2, tri3)
	if othera > a: return False
	othera += Mathutils.TriangleArea(pt, tri3, tri1)
	if othera > a: return False
	return True

Apply Matrix[edit | edit source]

Applys a 4x4 transformation as returned by object.getMatrix(), to a vector (3d point in space)

This is useful for finding out the position of a vertex in worldspace.

Blender 2.43 supports this simply by doing "newvwec = vec*matrix" but its good to know how to do it manually

# Apply Tpransform #
def apply_transform(vec, matrix):
	x, y, z = vec
	xloc, yloc, zloc = matrix[3][0], matrix[3][1], matrix[3][2]
	return	x*matrix[0][0] + y*matrix[1][0] + z*matrix[2][0] + xloc,\
			x*matrix[0][1] + y*matrix[1][1] + z*matrix[2][1] + yloc,\
			x*matrix[0][2] + y*matrix[1][2] + z*matrix[2][2] + zloc

def apply_transform3x3(vec, matrix):
	x, y, z = vec
	return x*matrix[0][0] + y*matrix[1][0] + z*matrix[2][0],\
			x*matrix[0][1] + y*matrix[1][1] + z*matrix[2][1],\
			x*matrix[0][2] + y*matrix[1][2] + z*matrix[2][2]

2D Line Intersection[edit | edit source]

Intersect 2 lines, if so where.

If there is no intersection the retured X value will be None and the y will be an error code.

The first line is (x1,y1, x2,y2), the second (_x1,_y1, _x2,_y2)

SMALL_NUM = 0.000001
def lineIntersection2D(x1,y1, x2,y2, _x1,_y1, _x2,_y2):
	# Bounding box intersection first.
	if min(x1, x2) > max(_x1, _x2) or \
	max(x1, x2) < min(_x1, _x2) or \
	min(y1, y2) > max(_y1, _y2) or \
	max(y1, y2) < min(_y1, _y2):
		return None, 100 # Basic Bounds intersection TEST returns false.
	# are either of the segments points? Check Seg1
	if abs(x1 - x2) + abs(y1 - y2) <= SMALL_NUM:
		return None, 101
	# are either of the segments points? Check Seg2
	if abs(_x1 - _x2) + abs(_y1 - _y2) <= SMALL_NUM:
		return None, 102
	# Make sure the HOZ/Vert Line Comes first.
	if abs(_x1 - _x2) < SMALL_NUM or abs(_y1 - _y2) < SMALL_NUM:
		x1, x2, y1, y2, _x1, _x2, _y1, _y2 = _x1, _x2, _y1, _y2, x1, x2, y1, y2
	if abs(x2-x1) < SMALL_NUM: # VERTICLE LINE
		if abs(_x2-_x1) < SMALL_NUM: # VERTICLE LINE SEG2
			return None, 111 # 2 verticle lines dont intersect.
		elif abs(_y2-_y1) < SMALL_NUM:
			return x1, _y1 # X of vert, Y of hoz. no calculation.		
		yi = ((_y1 / abs(_x1 - _x2)) * abs(_x2 - x1)) + ((_y2 / abs(_x1 - _x2)) * abs(_x1 - x1))
		if yi > max(y1, y2): # New point above seg1's vert line
			return None, 112
		elif yi < min(y1, y2): # New point below seg1's vert line
			return None, 113
		return x1, yi # Intersecting.
	if abs(y2-y1) < SMALL_NUM: # HOZ LINE
		if abs(_y2-_y1) < SMALL_NUM: # HOZ LINE SEG2
			return None, 121 # 2 hoz lines dont intersect.
		# Can skip vert line check for seg 2 since its covered above.	
		xi = ((_x1 / abs(_y1 - _y2)) * abs(_y2 - y1)) + ((_x2 / abs(_y1 - _y2)) * abs(_y1 - y1))
		if xi > max(x1, x2): # New point right of seg1's hoz line
			return None, 112
		elif xi < min(x1, x2): # New point left of seg1's hoz line
			return None, 113
		return xi, y1 # Intersecting.
	# Accounted for hoz/vert lines. Go on with both anglular.
	b1 = (y2-y1)/(x2-x1)
	b2 = (_y2-_y1)/(_x2-_x1)
	a1 = y1-b1*x1
	a2 = _y1-b2*_x1
	if b1 - b2 == 0.0:
		return None, None	
	xi = - (a1-a2)/(b1-b2)
	yi = a1+b1*xi
	if (x1-xi)*(xi-x2) >= 0 and (_x1-xi)*(xi-_x2) >= 0 and (y1-yi)*(yi-y2) >= 0 and (_y1-yi)*(yi-_y2)>=0:
		return xi, yi
		return None, None

Round to power of 2[edit | edit source]

This function takes any number and rounds it to the nearest power of 2 value (2,4,8,16,32,64,128,256,512,1024,2048, 4096...) This is useful for rounding textures to sized that load into graphics card memory.

It returns 3 values. rounded down, round closest, rounded up.

def roundPow2(roundVal):
	base2val = 1
	while roundVal >= base2val:
	# dont round up if there the same, just give the same vars
	if roundVal == base2val/2:
		return base2val/2, base2val/2, base2val/2 # Round down and round up.
	smallRound = base2val/2
	largeRound = base2val
	# closest to the base 2 value
	diffLower = abs(roundVal - smallRound)
	diffHigher = abs(roundVal - largeRound)
	if diffLower < diffHigher:
		mediumRound = smallRound
		mediumRound = largeRound
	smallRound = base2val/2
	largeRound = base2val
	return smallRound, mediumRound, largeRound # round down, round mid and round up.

Closest Point (snapping)[edit | edit source]

Returns the vector that is closest to point. Good for snapping.

def getSnapVec(point, snap_points):
	Returns the closest vec to snap_points
	close_dist= 1<<30
	close_vec= None

	x= point[0]
	y= point[1]
	z= point[2]
	for v in snap_points:
		# quick length cmp before a full length comparison.
		if abs(x-v[0]) < close_dist and\
		abs(y-v[1]) < close_dist and\
		abs(z-v[2]) < close_dist:
			l= (v-point).length
			if l<close_dist:
				close_dist= l
				close_vec= v
	return close_vec

Blender Object Scripts[edit | edit source]

Linked Duplicate Object[edit | edit source]

There is no function in B:Python to make a linked duplicate of an object (Alt+D) so here is a function that does it for you.

Note Since this was written Blender.Object.Duplicate() has been added as well as object.copy()

from Blender import *

# Like pressing Alt+D
def linkedCopy(ob, scn=None): # Just like Alt+D
	if not scn:
		scn = Scene.GetCurrent()
	type = ob.getType()
	newOb = Object.New(type)
	if type != 'Empty':
	# Copy other attributes.
	newOb.Layer = ob.Layer
        # Update the view
	return newOb

# You can call the function like this
	ob2duplicate = Object.GetSelected()[0]
	print "Nothing Selected"

Select Double Objects[edit | edit source]

Finds double object- objects that have the same dataname, type and loc/size/rot

Name: 'Select only double objects.'
Blender: 232
Group: 'Object'
Tooltip: 'Select double objects from the existing selection.'

from Blender import *

def main():
	# Collect the extra object data once only, so we dont need to request it again.
	obinfo = [{'object':ob, 'dataname':ob.getData(1), 'type':ob.getType(), 'matrix':tuple(ob.matrixWorld)} for ob in Object.GetSelected() ]
	print '\n\n\nStarting to select doubles for %i objects.' % len(obinfo)
	doubleObs = [] # store doubles in this list
	doubles = 0
	# Comparison loop, compare items in the list only once.
	obIdx1 = len(obinfo)
	while obIdx1:
		obIdx1 -=1
		ob1 = obinfo[obIdx1]
		# Deselect as we go, any doubles will be selected again.		ob1['object'].sel = 0
		ob1['object'].sel = 0
		obIdx2 = obIdx1
		while obIdx2:
			obIdx2 -=1
			ob2 = obinfo[obIdx2]
			# Comparison loop done.
			# Now we have both objects we can compare ob2 against ob1.
			if \
			ob1['dataname'] == ob2['dataname'] and\
			ob1['type']     == ob2['type'] and\
			ob1['matrix']   == ob2['matrix']:
				# We have a double, print output and add to the double list.
				doubles +=1
				print '\t%i doubles found: "%s", "%s"' % (doubles, ob1['object'].name, ob2['object'].name)

	for ob in doubleObs:
		ob['object'].sel = 1

if __name__ == '__main__':
	t = sys.time()
	print 'Done in %.4f seconds.' % (sys.time()-t)

NLA strips Examples[edit | edit source]

Example code for manipulating NLA strips and action strips

# Nov 16 2006
# Mike Stramba
# BlenderArtists  Mike_S

import Blender
from Blender import *
from Blender.Armature import NLA

ctr = 1
numStrips = 1

vflags ={32:'LOCK_ACTION',1:'SELECT',2:'STRIDE_PATH',8:'HOLD',16:'ACTIVE'}
def tranflag(flag):
	if flag:
		for v in vflags:
			t = flag & v
			if t:
				print '\t\t',v,vflags[t]

def showStrip(strip):
	print ctr,'/',numStrips
	print '\tstripStart',strip.stripStart
	print '\tstripEnd',strip.stripEnd
	print '\tactionStart',strip.actionStart
	print '\tactionEnd',strip.actionEnd
	print '\tblendin',strip.blendIn
	print '\tblendout',strip.blendOut

	print '\tflag',strip.flag,
	print '\tmode',strip.mode
	print '\tbrepeat',strip.repeat
	print '\tstrideAxis',strip.strideAxis
	print '\tstrideBone',strip.strideBone
	print '\tstrideLength',strip.strideLength



#  Actions named 'rot', 'move', 'Run' assumed to exist, or substitute
#  your own action names

rotAct = actions['rot']
movAct = actions['move']
runAct = actions['Run']

# get all NLA strips for this object

Char1NLAstrips = armOb.actionStrips

# set the current frame to where you want NLA strips to initially appear
# in the NLA editor

frame = 1

# remove all NLA strips

Char1NLAstrips[:] = []

#  some different ways of adding action strips to the NLA editor






#  get a strip

strip0 = Char1NLAstrips[0]

print '\ ="''"'

# show it's properties


# change it's stripStart, stripEND (add 50 frames)
#  (effectively moving the strip

strip0.stripEnd   += 50
strip0.stripStart += 50

# show the changes  


# select the strip in the NLA editor

strip0.flag += NLA.Flags['SELECT']


# move all strips by FrameOffset 

def moveallStrips(FrameOffset):
	for strip in Char1NLAstrips:
		strip.stripEnd   += FrameOffset
		strip.stripStart += FrameOffset


# show all strips Properties

print '============  ALL STRIPS ================'

numStrips = len(Char1NLAstrips)
print numStrips,' NLA strips for ',armOb
for strip in Char1NLAstrips:

Blender Windowing and User Interface Scripts[edit | edit source]

Mouse Location 3D Space[edit | edit source]

import Blender
from Blender import Mathutils, Window, Scene, Draw, Mesh
from Blender.Mathutils import Matrix, Vector, Intersect

# screen_x, screen_y the origin point of the pick ray
# it is either the mouse location
# localMatrix is used if you want to have the returned values in an objects localspace.
#    this is usefull when dealing with an objects data such as verts.
# or if useMid is true, the midpoint of the current 3dview
# returns
# Origin - the origin point of the pick ray
# Direction - the direction vector of the pick ray
# in global coordinates
epsilon = 1e-3 # just a small value to account for floating point errors

def getPickRay(screen_x, screen_y, localMatrix=None, useMid = False):
	# Constant function variables
	p = getPickRay.p
	d = getPickRay.d
	for win3d in Window.GetScreenInfo(Window.Types.VIEW3D): # we search all 3dwins for the one containing the point (screen_x, screen_y) (could be the mousecoords for example) 
		win_min_x, win_min_y, win_max_x, win_max_y = win3d['vertices']
		# calculate a few geometric extents for this window

		win_mid_x  = (win_max_x + win_min_x + 1.0) * 0.5
		win_mid_y  = (win_max_y + win_min_y + 1.0) * 0.5
		win_size_x = (win_max_x - win_min_x + 1.0) * 0.5
		win_size_y = (win_max_y - win_min_y + 1.0) * 0.5

		#useMid is for projecting the coordinates when we subdivide the screen into bins
		if useMid: # == True
			screen_x = win_mid_x
			screen_y = win_mid_y
		# if the given screencoords (screen_x, screen_y) are within the 3dwin we fount the right one...
		if (win_max_x > screen_x > win_min_x) and (  win_max_y > screen_y > win_min_y):
			# first we handle all pending events for this window (otherwise the matrices might come out wrong)
			# now we get a few matrices for our window...
			# sorry - i cannot explain here what they all do
			# - if you're not familiar with all those matrices take a look at an introduction to OpenGL...
			pm	= Window.GetPerspMatrix()   # the prespective matrix
			pmi  = Matrix(pm); pmi.invert() # the inverted perspective matrix
			if (1.0 - epsilon < pmi[3][3] < 1.0 + epsilon):
				# pmi[3][3] is 1.0 if the 3dwin is in ortho-projection mode (toggled with numpad 5)
				hms = getPickRay.hms
				ortho_d = getPickRay.ortho_d
				# ortho mode: is a bit strange - actually there's no definite location of the camera ...
				# but the camera could be displaced anywhere along the viewing direction.
				ortho_d.x, ortho_d.y, ortho_d.z = Window.GetViewVector()
				ortho_d.w = 0
				# all rays are parallel in ortho mode - so the direction vector is simply the viewing direction
				#hms.x, hms.y, hms.z, hms.w = (screen_x-win_mid_x) /win_size_x, (screen_y-win_mid_y) / win_size_y, 0.0, 1.0
				hms[:] = (screen_x-win_mid_x) /win_size_x, (screen_y-win_mid_y) / win_size_y, 0.0, 1.0
				# these are the homogenious screencoords of the point (screen_x, screen_y) ranging from -1 to +1
				p=(hms*pmi) + (1000*ortho_d)
				d[:] = ortho_d[:3]

			# Finally we shift the position infinitely far away in
			# the viewing direction to make sure the camera if outside the scene
			# (this is actually a hack because this function
			# is used in sculpt_mesh to initialize backface culling...)
				# PERSPECTIVE MODE: here everything is well defined - all rays converge at the camera's location
				vmi  = Matrix(Window.GetViewMatrix()); vmi.invert() # the inverse viewing matrix
				fp = getPickRay.fp
				dx = pm[3][3] * (((screen_x-win_min_x)/win_size_x)-1.0) - pm[3][0]
				dy = pm[3][3] * (((screen_y-win_min_y)/win_size_y)-1.0) - pm[3][1]
				fp[:] = \
				# fp is a global 3dpoint obtained from "unprojecting" the screenspace-point (screen_x, screen_y)
				#- figuring out how to calculate this took me quite some time.
				# The calculation of dxy and fp are simplified versions of my original code
				#- so it's almost impossible to explain what's going on geometrically... sorry
				p[:] = vmi[3][:3]
				# the camera's location in global 3dcoords can be read directly from the inverted viewmatrix
				d[:] = p.x-fp.x, p.y-fp.y, p.z-fp.z
			# the direction vector is simply the difference vector from the virtual camera's position
			#to the unprojected (screenspace) point fp
			# Do we want to return a direction in object's localspace?
			if localMatrix:
				localInvMatrix = Matrix(localMatrix)
				p = p*localInvMatrix
				d = d*localInvMatrix # normalize_v3
				p.x += localInvMatrix[3][0]
				p.y += localInvMatrix[3][1]
				p.z += localInvMatrix[3][2]
			#else: # Worldspace, do nothing
			return True, p, d # Origin, Direction	
	# Mouse is not in any view, return None.
	return False, None, None

# Constant function variables
getPickRay.d = Vector(0,0,0) # Perspective, 3d
getPickRay.p = Vector(0,0,0)
getPickRay.fp = Vector(0,0,0)

getPickRay.hms = Vector(0,0,0,0) # ortho only 4d
getPickRay.ortho_d = Vector(0,0,0,0) # ortho only 4d

def main():
	ob = Scene.GetCurrent().getActiveObject()
	me = ob.getData(mesh=1)
	# Loop until the mouse is in the view.
	mouseInView = False
	while not mouseInView: 
		screen_x, screen_y = Window.GetMouseCoords()
		mouseInView, Origin, Direction = getPickRay(screen_x, screen_y)
	if Window.GetMouseButtons() == 1 and mouseInView:
		i = 0
		time = Blender.sys.time()
		while Window.GetMouseButtons() == 1:
			screen_x, screen_y = Window.GetMouseCoords()
			mouseInView, Origin, Direction = getPickRay(screen_x, screen_y, ob.matrix)
			if mouseInView:
				me.verts[0].co.x = Origin.x
				me.verts[0].co.y = Origin.y
				me.verts[0].co.z = Origin.z
				me.verts[1].co.x = Origin.x - (Direction.x*1000)
				me.verts[1].co.y = Origin.y - (Direction.y*1000)
				me.verts[1].co.z = Origin.z - (Direction.z*1000)
		print '100 draws in %.6f' % (((Blender.sys.time()-time) / float(i))*100)

if __name__ == '__main__':

Auto Buttons[edit | edit source]

Auto Buttons is a really easy way to add a stack of buttons into any script.
Add the AutoButtons text to the bottom of any script and any function ending with _bgui will have a button that calls it.

# All functions to be displayed as buttons must use this suffix
GUI_SUFFIX= '_bgui'
BUTTON_LIST = [] # A list if dicts
EVENT = 1000

for func in dir():
	if func.endswith(GUI_SUFFIX):
		newButton = {}
		newButton['name'] = func[:-5].replace('_', ' ')[2:]
		newButton['func'] = func + '()'
		newButton['event'] = EVENT
		BUTTON_LIST.append( newButton )
def draw_gui():
	# find the width of the widest button
	button_height = 16; button_width = 100; ROW = 0
	for button in BUTTON_LIST:
		Draw.PushButton(button['name'], button['event'], 0, button_height*ROW, button_width, button_height, ''); ROW+=1
def handle_event(evt, val):
	if evt in (Draw.ESCKEY, Draw.QKEY) and not val:
def handle_button_event(evt):
	if evt >= EVENTNUM and evt < EVENTNUM + len(BUTTON_LIST):
		exec(BUTTON_LIST[evt - EVENTNUM]['func'])
		print 'invalid', evt
Draw.Register(draw_gui, handle_event, handle_button_event)

An example of a function that could use this

def Print_Object_Selection_bgui():
	Blender.Draw.PupMenu('|'.join( for ob in Blender.Object.GetSelected()))

Popup Menu Wrapper[edit | edit source]

This script takes a string that you would normally give to Draw.PupMenu() splitting up the menus by the groupsize.

def PupMenuLess(menu, groupSize=30):
	Works like Draw.PupMenu but will add a more/less buttons if the number of
	items is greater then the groupSize.
	more = ['   more...']
	less = ['   less...']
	menuList= menu.split('|')
	# No Less Needed, just call.
	if len(menuList) < groupSize:
		return Draw.PupMenu(menu)
	title = menuList[0].split('%t')[0]
	# Split the list into groups
	menuGroups = [[]]
	for li in menuList[1:]:
		if len(menuGroups[-1]) < groupSize:
	# Stores the current menu group we are looking at
	groupIdx = 0
	while True:
		# Give us a title with the menu number
		numTitle = [ ' '.join([title, str(groupIdx + 1), 'of', str(len(menuGroups)), '%t'])]
		if groupIdx == 0:
			menuString = '|'.join(numTitle + menuGroups[groupIdx] + more)
		elif groupIdx == len(menuGroups)-1:
			menuString = '|'.join(numTitle + less + menuGroups[groupIdx])
		else: # In the middle somewhere so Show a more and less
			menuString = '|'.join(numTitle + less + menuGroups[groupIdx] + more)
		result = Draw.PupMenu(menuString)
		# User Exit
		if result == -1:
			return -1
		if groupIdx == 0: # First menu
			if result-1 < groupSize:
				return result
			else: # must be more
				groupIdx +=1
		elif groupIdx == len(menuGroups): # Last Menu
			if result == 1: # Must be less
				groupIdx -= 1
			else: # Must be a choice
				return result + (groupIdx*groupSize)
			if result == 1: # Must be less
				groupIdx -= 1
			elif result-2 == groupSize:
				groupIdx +=1
				return result - 1 + (groupIdx*groupSize)

General Python[edit | edit source]

Here add general python code, useful when Python scripting.

Benchmark Script[edit | edit source]

Script that times different functions.

def loopFor():
	'''For loop test'''
	for i in xrange(1000000):
def loopWhile():
	'''While loop test'''
	while i<1000000:

def time_func(bench_func, iter=4):
	''' Run the function 10 times '''
	print '',bench_func.__doc__
	t= Blender.sys.time()
	for i in xrange(iter):
	tme= (Blender.sys.time()-t) / 10
	print '\tBenchmark %.4f average sec' % tme
	return tme

def main():
	print '\nRunning tests'

if __name__ == '__main__':

Iterate Multiple Lists[edit | edit source]

Sometimes you want to loop over more than 1 list at once. if the lists your dealing with are large then creating a new list for the purpose can be slow and use too much memory. This class takes multiple lists and treats them like 1 big list. without having to make a new list.

type_list= type([])
type_tuple= type(())
class listIter:
	def __init__(self, lists):
		if type(lists) != type_list:
			self.lists= list(lists)
			self.lists= lists
		self.idx= self.lidx= 0
	def next(self):
		if self.lidx==len(self.lists):
			raise StopIteration
		if self.idx==len(self.lists[self.lidx]):
			self.idx= 0
		return self.lists[lidx][idx]
	def __iter__(self):
		return self
	def __getitem__(self, index):
		for l in self.lists:
			if i+len(l)>index:
				return l[index-i]
		raise IndexError
	def __setitem__(self, index, value):
		for l in self.lists:
			if i+len(l)>index:
				l[index-i]= value
		raise IndexError
	def __len__(self):
		for l in self.lists:
		return length
	def index(self, value):
		for l in self.lists:
			for li in l:
				if li == value:
					return i
		raise ValueError
	def remove(self, value):
		for l in self.lists:
			if value in li:
		raise ValueError
	def count(self, value):
		return sum(l.count(value) for l in self.lists)
	def extend(self, value):
		for i in value: # See its an iterator
	def pop(self, index):
		for l in self.lists:
			if i+len(l)>index:
				return l.pop(index-i)
		raise IndexError
	def __str__(self):
		return '['+ ''.join(str(l)[1:-1] for l in self.lists) +']'
	def sort(self):
		'''Cant to a full sort, just do a par'''
		for l in self.lists:
	def append(self, value):
	def reverse(self):
		for l in self.lists:

Some examples

for i in listIter( (range(10), range(22), range(5)) ):
	print i

Another example that takes verts from 3 meshes and adds them to 1 mesh using this iterator and list comprehension.

from Blender import Mesh
newme= Mesh.New()

# Using the iterator
newme.verts.extend( [ for v in listIter((me1.verts, me2.verts, me3.verts))] )

# Without the iterator
newme.verts.extend( [ for v in me1.verts ] )
newme.verts.extend( [ for v in me2.verts ] )
newme.verts.extend( [ for v in me3.verts ] )

Binary Conversion (Without Struct)[edit | edit source]

Thanks to SJH 07/29/2004 20:26:03

nybblechr_to_01_dqs={'-':'-','0':'0000', '1':'0001', '2':'0010', '3':'0011',
                             '4':'0100', '5':'0101', '6':'0110', '7':'0111',
                             '8':'1000', '9':'1001', 'A':'1010', 'B':'1011',
                             'C':'1100', 'D':'1101', 'E':'1110', 'F':'1111'}

# Int to binary
def i2b(j, wd=0):
	return ''.join(nybblechr_to_01_dqs[x] for x in '%02X' % j))[-wd:].zfill(wd)
# Char to binary
def c2b(c, wd=0):
	return i2b(ord(c))
# String to binary
def s2b(s, wd=0):
	return ''.join(nybblechr_to_01_dqs[x] for x in ''.join('%02X' % ord(c) for c in s))[-wd:].zfill(wd)
# Binary to char
def b2c(b):

Randomize List[edit | edit source]

Returns a randomized list. Note if you can import random, use random.shuffle(ls) instead.

def randList(ls):
	lsCopy = ls[:]
	randList = []
	lenList = len(lsCopy)
	while lenList != len(randList):
		randIndex = int( Noise.random() * len(lsCopy)  )
		randList.append( lsCopy.pop( randIndex ) )
	return randList

Remove Doubles in List[edit | edit source]

Removes doubles in a list, modifying the original list. (will use an objects cmp() function)

def RemDoubles(List):
	lIdx = 0
	while lIdx < len(List):
		if List.count(List[lIdx]) > 1:

Remove Doubles in List (Hash)[edit | edit source]

Return a new list with no doubles.

def RemDoublesHash(myList):
	return list(set(myList))

Get flag properties of a sum[edit | edit source]

A lot of properties in Blender are flags and stored in a sum of exponentials of 2. To find out that a specific flag is set and it is included in the sum try this function:

def powList(self, x):
	tmpx = x
	exp = 0
	expList = []
	while tmpx != 0:	
		tmp = 2**exp
		if tmp > tmpx:
			elem = 2**(exp-1)
			tmpx -= elem	
			exp = 0
			exp += 1; 
	return expList

Call the function in that way:

lmp = Lamp.Get(
lmpMode = lmp.getMode()
lmpFlags = self.powList(lmpMode)
if 16 in lmpFlags:

Fraction Data Type[edit | edit source]

Allows creation of fraction data and all operations on them within the real number system.

class fraction:
	# Types without importing type - Does not retuire a python install.
	type_float = type(0.1)
	type_int = type(1)
	def __init__(self, num, den=1):
		if den == 0:
			raise ValueError, 'Division by zero'
		g = self.gcd(num, den)
		self.num = num / g
		self.den = den / g

	def __str__(self):
		return "%d/%d" % (self.num, self.den)

	def __mul__(self, other):
		if type(other) is fraction.type_int:
			other = fraction(other)
		elif type(other) is fraction.type_float:
			return self.eval() * other
		if not isinstance(other, fraction):
			raise ValueError, 'Unsupported operand type for multiply operation ' + str(type(other))
		return fraction(self.num * other.num, self.den * other.den)

	__rmul__ = __mul__

	def __add__(self, other):
		if type(other) is fraction.type_int:
			other = fraction(other)
		elif type(other) is fraction.type_float:
			return self.eval() + other
		if not isinstance(other, fraction):
			raise ValueError, 'Unsupported operand type for addition operation ' + str(type(other))
		num = self.num * other.den + self.den * other.num
		den = self.den * other.den
		return fraction(num, den)

	def __cmp__(self, other):
		if type(other) is fraction.type_int or type(other) is fraction.type_float:
			return self.eval() - other
		if not isinstance(other, fraction):
			raise ValueError, 'Comparative operation no supported for operand ' * type(other)
		return (self.num * other.den - other.num * self.den)

	def __neg__(self):	
		return fraction(self.num * -1, self.den)

	def __invert__(self):
		return fraction(self.den, self.num)

	def __sub__(self, other):
		return self + -other

	def __rsub__(self, other):
		return other + -self

	def __div__(self, other):
		return fraction(self.num, self.den) * fraction(other.den, other.num)
	def __rdiv__(self, other):
		return fraction(self.den, self.num) * fraction(other.num, other.den)
	def __pow__(self, other):
		if type(other) is fraction.type_int:
			return fraction(self.num ** other, self.den ** other)
		elif type(other) is fraction.type_float:
			a = self.eval()
			if a > 0:
				return a ** other
				raise ValueError, 'Negative number raised to fractional power'
		if not isinstance(other, fraction):
			raise ValueError, 'Unsupported operand type for exponential operation ' + str(type(other))
		return self.eval() ** other.eval()

	def gcd(self, m, n):
		if m % n:
			return self.gcd(n, m % n)
		return n
	def eval(self):
		return float(self.num) / self.den

##### Usage: #####

a = fraction(3, 4)
b = fraction(5, 6)
print a * b
print a - 3
print a ** b

#invalid - raising a negative number to a fractional power
print (-a)**b

Get a name with sane chars[edit | edit source]

This function can be used when you are making a filename from an object/mesh/scene... name. Blender supports many characters in a name that a filesystem may not.

saneFilechars replaces these characters with "_"

def saneFilechars(name):
	for ch in ' /\\~!@#$%^&*()+=[];\':",./<>?\t\r\n':
		name = name.replace(ch, '_')
	return name

Colour Scripts[edit | edit source]

A place for scripts that deal with colours.

RGB to HSV[edit | edit source]

Convert Red/Green/Blue to Hue/Saturation/Value

r,g,b values are from 0.0 to 1.0

h = [0,360], s = [0,1], v = [0,1]

if s == 0, then h = -1 (undefined)

The Hue/Saturation/Value model was created by A. R. Smith in 1978. It is based on such intuitive color characteristics as tint, shade and tone (or family, purety and intensity). The coordinate system is cylindrical, and the colors are defined inside a hexcone. The hue value H runs from 0 to 360º. The saturation S is the degree of strength or purity and is from 0 to 1. Purity is how much white is added to the color, so S=1 makes the purest color (no white). Brightness V also ranges from 0 to 1, where 0 is the black.

def RGBtoHSV(R,G,B):
	# min, max, delta;
	min_rgb = min( R, G, B )
	max_rgb = max( R, G, B )
	V = max_rgb

	delta = max_rgb - min_rgb
	if not delta:
		H = 0
		S = 0
		V = R # RGB are all the same.
		return H,S,V
	elif max_rgb: # != 0
		S = delta / max_rgb
		R = G = B = 0 # s = 0, v is undefined
		S = 0
		H = 0 # -1
		return H,S,V

	if R == max_rgb:
		H = ( G - B ) / delta # between yellow & magenta
	elif G == max_rgb:
		H = 2 + ( B - R ) / delta # between cyan & yellow
		H = 4 + ( R - G ) / delta # between magenta & cyan

	H *= 60 # convert to deg
	if H < 0:
		H += 360
	return H,S,V

HSV to RGB[edit | edit source]

Convert Hue/Saturation/Value to Red/Green/Blue

def HSVtoRGB(H,S,V):
	if not S: # S == 0
		# achromatic (grey)
		# R = G = B = V
		return V,V,V # RGB == VVV
	H /= 60;			# sector 0 to 5
	i = int( H ) # round down to int. in C its floor()
	f = H - i			# factorial part of H
	p = V * ( 1 - S )
	q = V * ( 1 - S * f )
	t = V * ( 1 - S * ( 1 - f ) )
	if i == 0:
		R,G,B = V,t,p
	elif i == 1:
		R,G,B = q,V,p
	elif i == 2:
		R,G,B = p,V,t
	elif i == 3:
		R,G,B = p,q,V
	elif i == 4:
		R,G,B = t,p,V
	else: # 5
		R,G,B = V,p,q
	return R,G,B

Interactive Tools[edit | edit source]

Freehand Polyline Draw Tool[edit | edit source]

from Blender import *

def main():
        # New Curve and add to Scene.
        scn = Scene.GetCurrent()
        cu = Curve.New()
        # cu.setResolu(1)
        x=y=z=w=t = 1
        cu[0].type = 0 # Poly line
        ob = Object.New('Curve')
        ob.sel = 1 # Make active and selected

        # Initialize progress bar for writing
        Window.DrawProgressBar(0.0, '')

        ticker = 0.0 # Used to cycle the progress bar

        # Pause before drawing
        while not Window.GetMouseButtons() & Window.MButs['L']:

                Window.DrawProgressBar(ticker, 'Left Mouse to Draw')
                ticker += 0.01
                if ticker > 0.98: ticker = 0

        oldx=oldy = -100000
        # Mouse Clicked, lets draw
        while Window.GetMouseButtons() & Window.MButs['L']:
                x,y = Window.GetMouseCoords()
                print abs(x-oldx)+abs(y-oldy)
                if (oldx == x and oldy == y) or abs(x-oldx)+abs(y-oldy) < 10: # Mouse must have moved 10 before adding the next point
                        z = 0 # 2D Drawing for now
                        w = 100 #Weight is 1
                        cu.appendPoint(0, [x*0.001,y*0.001,z,w]) # Can add tilt here.

                        Window.DrawProgressBar(ticker, 'Drawing...')
                        ticker += 0.01
                        if ticker > 0.98: ticker = 0

                        oldx,oldy = x,y # Store the old mouse location to compare with new.

        # Clear the progress bar
        Window.DrawProgressBar(1.0, '')


Render Functions[edit | edit source]

Render to a dir[edit | edit source]

# recursive dir creation.
def _mkdir(newdir):
	import os, sys
	"""works the way a good mkdir should :)
			- already exists, silently complete
			- regular file in the way, raise an exception
			- parent directory(ies) does not exist, make them as well
	if os.path.isdir(newdir):
	elif sys.exists(newdir):
		raise OSError("a file with the same name as the desired " \
						      "dir, '%s', already exists." % newdir)
			head, tail = os.path.split(newdir)
			if head and not os.path.isdir(head):
			#print "_mkdir %s" % repr(newdir)
			if tail:

from Blender import *
from Blender.Scene import Render
if sys.sep == '\\':

# Should probably create the paths if not existing.

scene= Scene.GetCurrent()
context = scene.getRenderingContext()


Render from all cameras[edit | edit source]

This script renders an animation from all cameras in a scene, it makes a new name from the camera and leaves the scene as it was originally.

Be sure to use useful camera names.

from Blender import Object, Scene

sce= Scene.GetCurrent()
context = sce.getRenderingContext()
output_path_orig= context.getRenderPath()

cams= [ob for ob in sce.getChildren() if ob.getType()=='Camera']

# backup the active cam.
orig_cam= sce.getCurrentCamera()

# loop over all the cameras in this scene, set active and render.
for i, c in enumerate(cams):
	print '\tRendering %i of %i cameras.' % (i, len(cams))
	context.setRenderPath('%s_%s_' % (output_path_orig, # use a unique name
	sce.setCurrentCamera(c) # set this camera to be active.
print 'Done per camera render'	

if orig_cam:
	sce.setCurrentCamera(orig_cam) # restore the original cam

# restore the original path.

Scriptlinks[edit | edit source]

Monitor Image[edit | edit source]

This Script needs to be used as a redraw scriptlink. It checks the date of the current image and attempts to reload the image, and if successful it redraws the image.

import Blender
import os
img= Blender.Image.GetCurrent() # currently displayed picture.
if img: # Image isnt None
	path= Blender.sys.expandpath(img.filename)
	if Blender.sys.exists(path):
		t= os.path.getctime(path)
		if t != Blender.my_image_time:
		Blender.my_image_time= t # global, persists between running the scripts.

Dynamic Text[edit | edit source]

This script needs to be used as a FrameChanged script linked to a Text object. Change the Years.append line to choice the years of the timeline.

import Blender as B 

Years = [] 

# year = [year, initial frame, duration of frames] 
Years.append([1800, 1, 10])
Years.append([1850, 100, 50]) 
Years.append([1994, 170, 100]) 
Years.append([2008, 300, 50])
Years.append([2050, 400, 50]) 
def when (frame,  years): 
    iniY = 0 
    for y in range(len(years)): 
        if frame > years[y][1]: 
            iniY = y 
    iniYear       = years[iniY][0] 
    iniFrame      = years[iniY][1] 
    iniFrameDelay = years[iniY][2] 
    finYear  = years[iniY+1][0] 
    finFrame = years[(iniY+1)][1] 
    frameRange = finFrame - (iniFrame + iniFrameDelay) 
    yearRange = finYear - iniYear 
    normFrame = float(frame - iniFrame - iniFrameDelay) 
    normFrame = normFrame/frameRange 
    if normFrame > 0: 
        newYear = str(int(iniYear + (yearRange * normFrame))) 
        newYear = iniYear 
    return str(newYear) 
if B.bylink: 
    actualFrame = B.Get("curframe") 
    year = 
    dynYear = year.getData()      
    newYear=when (actualFrame,Years) 
    if newYear != oldYear: 

External Utils[edit | edit source]

Compress All Blend files (Unix Only)[edit | edit source]

Sine blender 2.41, support for GZip compression has been integrated into blender. So you can gzip all blend files and they will still open as expected.

This utility searches your hard-disk for blend files and gzips them if they are not already compressed.

Note: python3 required.


root_dir = '/mango/pro'

import os
import os.path

def blend_path_list(path):
    for dirpath, dirnames, filenames in os.walk(path):
        for filename in filenames:
            if filename.endswith(".blend"):
                yield os.path.join(dirpath, filename)

def isblend_nogz(path):
        f = open(path, 'rb')
        is_blend = ( == b'BLENDER')
        return is_blend
        return False

def main():
    print('Searching "%s"...' % root_dir)
    files = list(blend_path_list(root_dir))
    #print files
    tot_files = len(files)
    tot_compressed = tot_blends = tot_alredy_compressed = 0
    tot_blend_size = 0
    tot_blend_size_saved = 0
    for f in files:
        if len(f) >= 6:  # .blend is 6 chars
            f_lower = f.lower()
            if (f_lower.endswith(".blend") or
                f_lower[:-1].endswith(".blend") or
                f_lower[:-2].endswith(".blend")):  # .blend10 +

                print(f, "...", end="")
                tot_blends += 1
                # allows for dirs with .blend, will just be false.
                if isblend_nogz(f):
                    print("compressing ...", end="")
                    tot_compressed += 1
                    orig_size = os.path.getsize(f)
                    tot_blend_size += orig_size
                    os.system('gzip --best "%s"' % f)
                    os.system('mv "%s.gz" "%s"' % (f, f)) # rename the gz file to the original.
                    new_size = os.path.getsize(f)
                    tot_blend_size_saved += orig_size - new_size
                    print('saved %.2f%%' % (100 - (100 * (float(new_size) / orig_size))))
                    print('alredy compressed.')
                    tot_alredy_compressed += 1

    print('\nTotal files:', tot_files)
    print('Total Blend:', tot_blends)
    print('Total Blend Compressed:', tot_compressed)
    print('Total Alredy Compressed:', tot_alredy_compressed)
    print('\nTotal Size in Blends: %sMB' % (((tot_blend_size) / 1024) / 1024))
    print('Total Saved in Blends: %sMB' % (((tot_blend_size_saved) / 1024) / 1024))

if __name__ == '__main__':