blender/release/scripts/obj_export.py

#!BPY

"""
Name: 'Wavefront (.obj)...'
Blender: 232
Group: 'Export'
Tooltip: 'Save a Wavefront OBJ File'
"""

# --------------------------------------------------------------------------
# OBJ Export v0.9 by Campbell Barton (AKA Ideasman)
# --------------------------------------------------------------------------
# ***** BEGIN GPL LICENSE BLOCK *****
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
#
# ***** END GPL LICENCE BLOCK *****
# --------------------------------------------------------------------------

#==================================================#
# New name based on old with a different extension #
#==================================================#
def newFName(ext):
  return Get('filename')[: -len(Get('filename').split('.', -1)[-1]) ] + ext


#===============================================#
# Strips the slashes from the front of a string #
#===============================================#
def stripPath(path):
	for CH in range(len(path), 0, -1):
		if path[CH-1] == "/" or path[CH-1] == "\\":
			path = path[CH:]
			break	
	return path


#==================#
# Apply Transform  #
#==================#
def apply_transform(vert, matrix):
	vertCopy = Mathutils.CopyVec(vert)
	vertCopy.resize4D()
	return Mathutils.VecMultMat(vertCopy, matrix)

#====================================================#
# Return a 6 deciaml point floating point value      #
# as a string that dosent have any python chars      #
#====================================================#
def saneFloat(float):
  #return '%(float)b' % vars()  # 6 fp as house.hqx
  return str('%f' % float) + ' '


from Blender import *

NULL_MAT = '(null)'
NULL_IMG = '(null)'

def save_mtl(filename):
	file = open(filename, "w")
	for mat in Material.Get():
		
		file.write('newmtl ' + mat.getName() + '\n') # Define a new material
		
		file.write('Ns ' + saneFloat((mat.getHardness()-1) * 1.9607843137254901 ) + '\n') # Hardness, convert blenders 1-511 to MTL's 
		
		col = mat.getRGBCol()
		file.write('Kd ' + saneFloat(col[0]) + saneFloat(col[1])  + saneFloat(col[2]) +'\n') # Diffuse
		
		col = mat.getMirCol()
		file.write('Ka ' + saneFloat(col[0]) + saneFloat(col[1])  + saneFloat(col[2]) + '\n') # Ambient, uses mirror colour,
		
		col = mat.getSpecCol()
		file.write('Ks ' + saneFloat(col[0]) + saneFloat(col[1])  + saneFloat(col[2]) +'\n') # Specular
		
		file.write('d ' + saneFloat(mat.getAlpha()) +'\n') # Alpha (dissolve)
		
		# illum, 0 to disable lightng, 2 is normal.
		file.write('illum ')
		if mat.getMode() & Material.Modes['SHADELESS']:
			file.write('0\n') # ignore lighting
		else:
			file.write('2\n') # light normaly
		
		# End OF Mat
		file.write('\n') # new line
		
	file.close()



def save_obj(filename):
  
  # First output all material
  mtlfilename = filename[:-4] + '.mtl'
  save_mtl(mtlfilename)
  
  file = open(filename, "w")
  
  # Write Header
  file.write('# Blender OBJ File: ' + Get('filename') + ' \n')
  file.write('# www.blender.org\n')
  
  # Tell the obj file what file to use.
  file.write('mtllib ' + stripPath(mtlfilename) + ' \n')   
  
  # Initialize totals, these are updated each object
  totverts = totuvco = 0
  
  
  # Get all meshs
  for ob in Object.Get():
     if ob.getType() == 'Mesh':
        m = ob.getData()
        if len(m.verts) > 0: # Make sure there is somthing to write.
          
          # Set the default mat
          currentMatName = NULL_MAT
          currentImgName = NULL_IMG
          
          file.write('o ' + ob.getName() + '_' + m.name + '\n') # Write Object name
          
          # Works 100% Yay
          matrix = ob.getMatrix('worldspace')
          
          # Vert
          for v in m.verts:
            # Transform the vert
            vTx = apply_transform(v.co, matrix)
            
            file.write('v ')
            file.write(saneFloat(vTx[0]))
            file.write(saneFloat(vTx[1]))
            file.write(saneFloat(vTx[2]) + '\n')
          
          # UV
          for f in m.faces:
             if len(f.v) > 2:
                for uvIdx in range(len(f.v)):
                  file.write('vt ')
                  if f.uv:
                    file.write(saneFloat(f.uv[uvIdx][0]))
                    file.write(saneFloat(f.uv[uvIdx][1]))
                  else:
                    file.write('0.0 ')
                    file.write('0.0 ')
                     
                  file.write('0.0' + '\n')
          
          # NORMAL
          for f1 in m.faces:
             if len(f1.v) > 2:
                for v in f1.v:
                   # Transform the normal
                   noTx = apply_transform(v.no, matrix)
                   noTx.normalize()
                   file.write('vn ')
                   file.write(saneFloat(noTx[0]))
                   file.write(saneFloat(noTx[1]))
                   file.write(saneFloat(noTx[2]) + '\n')
          
          uvIdx = 0
          for f in m.faces:
             if len(f.v) > 2:
                # Check material and change if needed.
                if len(m.materials) > f.mat:
                   if currentMatName != m.materials[f.mat].getName():
                      currentMatName = m.materials[f.mat].getName()
                      file.write('usemtl ' + currentMatName + '\n')
                  
                elif currentMatName != NULL_MAT:
                   currentMatName = NULL_MAT
                   file.write('usemtl ' + currentMatName + '\n')
                
                # UV IMAGE
                # If the face uses a different image from the one last set then add a usemap line.
                if f.image:
                  if f.image.filename != currentImgName:
                    currentImgName = f.image.filename
                    file.write( 'usemat ' + stripPath(currentImgName) +'\n') # Set a new image for all following faces
                    
                elif currentImgName != NULL_IMG: # Not using an image so set to NULL_IMG
                  currentImgName = NULL_IMG
                  file.write( 'usemat ' + stripPath(currentImgName) +'\n') # Set a new image for all following faces
                
                file.write('f ')
                for v in f.v:
                  file.write( str(m.verts.index(v) + totverts +1) + '/') # Vert IDX
                  file.write( str(uvIdx + totuvco +1) + '/') # UV IDX
                  file.write( str(uvIdx + totuvco +1) + ' ') # NORMAL IDX
                  uvIdx+=1
                file.write('\n')
        
        # Make the indicies global rather then per mesh
        totverts += len(m.verts)
        totuvco += uvIdx
  file.close()

Window.FileSelector(save_obj, 'Export Wavefront OBJ', newFName('obj'))