Software Público Brasileiro

#--------------------------------------------------------------------------
# Software:     InVesalius - Software de Reconstrucao 3D de Imagens Medicas
# Copyright:    (C) 2001  Centro de Pesquisas Renato Archer
# Homepage:     http://www.softwarepublico.gov.br
# Contact:      invesalius@cti.gov.br
# License:      GNU - GPL 2 (LICENSE.txt/LICENCA.txt)
#--------------------------------------------------------------------------
#    Este programa e software livre; voce pode redistribui-lo e/ou
#    modifica-lo sob os termos da Licenca Publica Geral GNU, conforme
#    publicada pela Free Software Foundation; de acordo com a versao 2
#    da Licenca.
#
#    Este programa eh distribuido na expectativa de ser util, mas SEM
#    QUALQUER GARANTIA; sem mesmo a garantia implicita de
#    COMERCIALIZACAO ou de ADEQUACAO A QUALQUER PROPOSITO EM
#    PARTICULAR. Consulte a Licenca Publica Geral GNU para obter mais
#    detalhes.
#--------------------------------------------------------------------------

import multiprocessing
import os
import plistlib
import random
import tempfile
import weakref

import vtk
import wx
from wx.lib.pubsub import pub as Publisher

import constants as const
import imagedata_utils as iu
import polydata_utils as pu
import project as prj
import session as ses
import surface_process
import utils as utl
import vtk_utils as vu

try:
    import ca_smoothing
except ImportError:
    import data.ca_smoothing as ca_smoothing

class Surface():
    """
    Represent both vtkPolyData and associated properties.
    """
    general_index = -1
    def __init__(self, index=None, name=""):
        Surface.general_index += 1
        if index is None:
            self.index = Surface.general_index
        else:
            self.index = index
            Surface.general_index -= 1
        self.polydata = ''
        self.colour = ''
        self.transparency = const.SURFACE_TRANSPARENCY
        self.volume = 0
        self.is_shown = 1
        self.temp_file = ''
        if not name:
            self.name = const.SURFACE_NAME_PATTERN %(self.index+1)
        else:
            self.name = name

    def SavePlist(self, dir_temp, filelist):
        filename = 'surface_%d' % self.index
        vtp_filename = filename + '.vtp'
        vtp_filepath = os.path.join(dir_temp, vtp_filename)
        pu.Export(self.polydata, vtp_filepath, bin=True)

        filelist[vtp_filepath] = vtp_filename

        surface = {'colour': self.colour,
                   'index': self.index,
                   'name': self.name,
                   'polydata': vtp_filename,
                   'transparency': self.transparency,
                   'visible': bool(self.is_shown),
                   'volume': self.volume,
                  }
        plist_filename = filename + '.plist'
        #plist_filepath = os.path.join(dir_temp, filename + '.plist')
        temp_plist = tempfile.mktemp()
        plistlib.writePlist(surface, temp_plist)

        filelist[temp_plist] = plist_filename

        return plist_filename

    def OpenPList(self, filename):
        sp = plistlib.readPlist(filename)
        dirpath = os.path.abspath(os.path.split(filename)[0])
        self.index = sp['index']
        self.name = sp['name']
        self.colour = sp['colour']
        self.transparency = sp['transparency']
        self.is_shown = sp['visible']
        self.volume = sp['volume']
        self.polydata = pu.Import(os.path.join(dirpath, sp['polydata']))
        Surface.general_index = max(Surface.general_index, self.index)

    def save_workdir(self):
        surface = {'colour': self.colour,
                   'index': self.index,
                   'name': self.name,
                   'polydata': self.temp_file,
                   'transparency': self.transparency,
                   'visible': bool(self.is_shown),
                   'volume': self.volume,
                  }
        plist_filename = os.path.splitext(self.temp_file)[0] + '.plist'
        plistlib.writePlist(surface, plist_filename)
        return os.path.split(plist_filename)[-1]

    def _set_class_index(self, index):
        Surface.general_index = index


# TODO: will be initialized inside control as it is being done?
class SurfaceManager():
    """
    Responsible for:
     - creating new surfaces;
     - managing surfaces' properties;
     - removing existing surfaces.

    Send pubsub events to other classes:
     - GUI: Update progress status
     - volume_viewer: Sends surface actors as the are created

    """
    def __init__(self):
        self.actors_dict = {}
        self.last_surface_index = 0
        self.__bind_events()

    def __bind_events(self):
        Publisher.subscribe(self.AddNewActor, 'Create surface')
        Publisher.subscribe(self.SetActorTransparency,
                                 'Set surface transparency')
        Publisher.subscribe(self.SetActorColour,
                                 'Set surface colour')

        Publisher.subscribe(self.OnChangeSurfaceName, 'Change surface name')
        Publisher.subscribe(self.OnShowSurface, 'Show surface')
        Publisher.subscribe(self.OnExportSurface,'Export surface to file')
        Publisher.subscribe(self.OnLoadSurfaceDict, 'Load surface dict')
        Publisher.subscribe(self.OnCloseProject, 'Close project data')
        Publisher.subscribe(self.OnSelectSurface, 'Change surface selected')
        #----
        Publisher.subscribe(self.OnSplitSurface, 'Split surface')
        Publisher.subscribe(self.OnLargestSurface,
                                'Create surface from largest region')
        Publisher.subscribe(self.OnSeedSurface, "Create surface from seeds")

        Publisher.subscribe(self.OnDuplicate, "Duplicate surfaces")
        Publisher.subscribe(self.OnRemove,"Remove surfaces")
        Publisher.subscribe(self.UpdateSurfaceInterpolation, 'Update Surface Interpolation')

    def OnDuplicate(self, pubsub_evt):
        selected_items = pubsub_evt.data
        proj = prj.Project()
        surface_dict = proj.surface_dict
        for index in selected_items:
            original_surface = surface_dict[index]
            # compute copy name
            name = original_surface.name
            names_list = [surface_dict[i].name for i in surface_dict.keys()]
            new_name = utl.next_copy_name(name, names_list)
            # create new mask
            self.CreateSurfaceFromPolydata(polydata = original_surface.polydata,
                                           overwrite = False,
                                           name = new_name,
                                           colour = original_surface.colour,
                                           transparency = original_surface.transparency,
                                           volume = original_surface.volume)

    def OnRemove(self, pubsub_evt):
        selected_items = pubsub_evt.data
        proj = prj.Project()

        old_dict = self.actors_dict
        new_dict = {}
        if selected_items:
            for index in selected_items:
                proj.RemoveSurface(index)
                actor = old_dict[index]
                for i in old_dict:
                    if i < index:
                        new_dict[i] = old_dict[i]
                    if i > index:
                        new_dict[i-1] = old_dict[i]
                old_dict = new_dict
                Publisher.sendMessage('Remove surface actor from viewer', actor)
            self.actors_dict = new_dict

        if self.last_surface_index in selected_items:
            if self.actors_dict:
                self.last_surface_index = 0
            else:
                self.last_surface_index = None

    def OnSeedSurface(self, pubsub_evt):
        """
        Create a new surface, based on the last selected surface,
        using as reference seeds user add to surface of reference.
        """
        points_id_list = pubsub_evt.data
        index = self.last_surface_index
        proj = prj.Project()
        surface = proj.surface_dict[index]

        new_polydata = pu.JoinSeedsParts(surface.polydata,
                                          points_id_list)
        index = self.CreateSurfaceFromPolydata(new_polydata)
        Publisher.sendMessage('Show single surface', (index, True))
        #self.ShowActor(index, True)

    def OnSplitSurface(self, pubsub_evt):
        """
        Create n new surfaces, based on the last selected surface,
        according to their connectivity.
        """
        index = self.last_surface_index
        proj = prj.Project()
        surface = proj.surface_dict[index]

        index_list = []
        new_polydata_list = pu.SplitDisconectedParts(surface.polydata)
        for polydata in new_polydata_list:
            index = self.CreateSurfaceFromPolydata(polydata)
            index_list.append(index)
            #self.ShowActor(index, True)

        Publisher.sendMessage('Show multiple surfaces', (index_list, True))

    def OnLargestSurface(self, pubsub_evt):
        """
        Create a new surface, based on largest part of the last
        selected surface.
        """
        index = self.last_surface_index
        proj = prj.Project()
        surface = proj.surface_dict[index]

        new_polydata = pu.SelectLargestPart(surface.polydata)
        new_index = self.CreateSurfaceFromPolydata(new_polydata)
        Publisher.sendMessage('Show single surface', (new_index, True))

    def CreateSurfaceFromPolydata(self, polydata, overwrite=False,
                                  name=None, colour=None,
                                  transparency=None, volume=None):
        normals = vtk.vtkPolyDataNormals()
        normals.SetInput(polydata)
        normals.SetFeatureAngle(80)
        normals.AutoOrientNormalsOn()

        mapper = vtk.vtkPolyDataMapper()
        mapper.SetInput(normals.GetOutput())
        mapper.ScalarVisibilityOff()
        mapper.ImmediateModeRenderingOn() # improve performance

        actor = vtk.vtkActor()
        actor.SetMapper(mapper)

        if overwrite:
            surface = Surface(index = self.last_surface_index)
        else:
            surface = Surface()

        if not colour:
            surface.colour = random.choice(const.SURFACE_COLOUR)
        else:
            surface.colour = colour
        surface.polydata = polydata

        if transparency:
            surface.transparency = transparency

        if name:
            surface.name = name

        # Append surface into Project.surface_dict
        proj = prj.Project()
        if overwrite:
            proj.ChangeSurface(surface)
        else:
            index = proj.AddSurface(surface)
            surface.index = index
            self.last_surface_index = index

        wdir = proj.working_dir
        temp_file = tempfile.mktemp(prefix='surface%d_' % surface.index, suffix='.vtp', dir=wdir)

        writer = vtk.vtkXMLPolyDataWriter()
        writer.SetInput(polydata)
        writer.SetFileName(temp_file)
        writer.Write()
        del writer

        surface.temp_file = temp_file

        # Set actor colour and transparency
        actor.GetProperty().SetColor(surface.colour)
        actor.GetProperty().SetOpacity(1-surface.transparency)
        self.actors_dict[surface.index] = actor

        session = ses.Session()
        session.ChangeProject()

        # The following lines have to be here, otherwise all volumes disappear
        if not volume:
            triangle_filter = vtk.vtkTriangleFilter()
            triangle_filter.SetInput(polydata)
            triangle_filter.Update()

            measured_polydata = vtk.vtkMassProperties()
            measured_polydata.SetInput(triangle_filter.GetOutput())
            volume =  measured_polydata.GetVolume()
            surface.volume = volume
            print ">>>>", surface.volume
        else:
            surface.volume = volume
        self.last_surface_index = surface.index

        Publisher.sendMessage('Load surface actor into viewer', actor)

        Publisher.sendMessage('Update surface info in GUI',
                                        (surface.index, surface.name,
                                        surface.colour, surface.volume,
                                        surface.transparency))

        return surface.index

    def OnCloseProject(self, pubsub_evt):
        self.CloseProject()

    def CloseProject(self):
        for index in self.actors_dict:
            Publisher.sendMessage('Remove surface actor from viewer', self.actors_dict[index])
        del self.actors_dict
        self.actors_dict = {}

    def OnSelectSurface(self, pubsub_evt):
        index = pubsub_evt.data
        #self.last_surface_index = index
        # self.actors_dict.
        proj = prj.Project()
        surface = proj.surface_dict[index]
        Publisher.sendMessage('Update surface info in GUI',
                                    (index, surface.name,
                                    surface.colour, surface.volume,
                                    surface.transparency))
        self.last_surface_index = index
        if surface.is_shown:
            self.ShowActor(index, True)

    def OnLoadSurfaceDict(self, pubsub_evt):
        surface_dict = pubsub_evt.data
        for key in surface_dict:
            surface = surface_dict[key]
            # Map polygonal data (vtkPolyData) to graphics primitives.
            normals = vtk.vtkPolyDataNormals()
            normals.SetInput(surface.polydata)
            normals.SetFeatureAngle(80)
            normals.AutoOrientNormalsOn()
            normals.GetOutput().ReleaseDataFlagOn()

	    # Improve performance
            stripper = vtk.vtkStripper()
            stripper.SetInput(normals.GetOutput())
            stripper.PassThroughCellIdsOn()
            stripper.PassThroughPointIdsOn()

            mapper = vtk.vtkPolyDataMapper()
            mapper.SetInput(stripper.GetOutput())
            mapper.ScalarVisibilityOff()
            mapper.ImmediateModeRenderingOn() # improve performance

            # Represent an object (geometry & properties) in the rendered scene
            actor = vtk.vtkActor()
            actor.SetMapper(mapper)

            # Set actor colour and transparency
            actor.GetProperty().SetColor(surface.colour)
            actor.GetProperty().SetOpacity(1-surface.transparency)

            self.actors_dict[surface.index] = actor

            # Send actor by pubsub to viewer's render
            Publisher.sendMessage('Load surface actor into viewer', (actor))

            Publisher.sendMessage('Update status text in GUI',
                                        _("Ready"))

            # The following lines have to be here, otherwise all volumes disappear
            Publisher.sendMessage('Update surface info in GUI',
                                        (surface.index, surface.name,
                                        surface.colour, surface.volume,
                                        surface.transparency))
            if not surface.is_shown:
                self.ShowActor(key, False)

    ####
    #(mask_index, surface_name, quality, fill_holes, keep_largest)

    def AddNewActor(self, pubsub_evt):
        """
        Create surface actor, save into project and send it to viewer.
        """
        slice_, mask, surface_parameters = pubsub_evt.data
        matrix = slice_.matrix
        filename_img = slice_.matrix_filename
        spacing = slice_.spacing

        algorithm = surface_parameters['method']['algorithm']
        options = surface_parameters['method']['options']

        surface_name = surface_parameters['options']['name']
        quality = surface_parameters['options']['quality']
        fill_holes = surface_parameters['options']['fill']
        keep_largest = surface_parameters['options']['keep_largest']

        mode = 'CONTOUR' # 'GRAYSCALE'
        min_value, max_value = mask.threshold_range
        colour = mask.colour

        try:
            overwrite = surface_parameters['options']['overwrite']
        except KeyError:
            overwrite = False
        mask.matrix.flush()

        if quality in const.SURFACE_QUALITY.keys():
            imagedata_resolution = const.SURFACE_QUALITY[quality][0]
            smooth_iterations = const.SURFACE_QUALITY[quality][1]
            smooth_relaxation_factor = const.SURFACE_QUALITY[quality][2]
            decimate_reduction = const.SURFACE_QUALITY[quality][3]

        #if imagedata_resolution:
            #imagedata = iu.ResampleImage3D(imagedata, imagedata_resolution)

        pipeline_size = 4
        if decimate_reduction:
            pipeline_size += 1
        if (smooth_iterations and smooth_relaxation_factor):
            pipeline_size += 1
        if fill_holes:
            pipeline_size += 1
        if keep_largest:
            pipeline_size += 1

        ## Update progress value in GUI
        UpdateProgress = vu.ShowProgress(pipeline_size)
        UpdateProgress(0, _("Creating 3D surface..."))

        language = ses.Session().language

        if (prj.Project().original_orientation == const.CORONAL):
            flip_image = False
        else:
            flip_image = True

        n_processors = multiprocessing.cpu_count()

        pipe_in, pipe_out = multiprocessing.Pipe()
        o_piece = 1
        piece_size = 2000

        n_pieces = int(round(matrix.shape[0] / piece_size + 0.5, 0))

        q_in = multiprocessing.Queue()
        q_out = multiprocessing.Queue()

        p = []
        for i in xrange(n_processors):
            sp = surface_process.SurfaceProcess(pipe_in, filename_img,
                                                matrix.shape, matrix.dtype,
                                                mask.temp_file,
                                                mask.matrix.shape,
                                                mask.matrix.dtype,
                                                spacing,
                                                mode, min_value, max_value,
                                                decimate_reduction,
                                                smooth_relaxation_factor,
                                                smooth_iterations, language,
                                                flip_image, q_in, q_out,
                                                algorithm != 'Default',
                                                algorithm,
                                                imagedata_resolution)
            p.append(sp)
            sp.start()

        for i in xrange(n_pieces):
            init = i * piece_size
            end = init + piece_size + o_piece
            roi = slice(init, end)
            q_in.put(roi)
            print "new_piece", roi

        for i in p:
            q_in.put(None)

        none_count = 1
        while 1:
            msg = pipe_out.recv()
            if(msg is None):
                none_count += 1
            else:
                UpdateProgress(msg[0]/(n_pieces * pipeline_size), msg[1])

            if none_count > n_pieces:
                break

        polydata_append = vtk.vtkAppendPolyData()
        polydata_append.ReleaseDataFlagOn()
        t = n_pieces
        while t:
            filename_polydata = q_out.get()

            reader = vtk.vtkXMLPolyDataReader()
            reader.SetFileName(filename_polydata)
            reader.ReleaseDataFlagOn()
            reader.Update()
            reader.GetOutput().ReleaseDataFlagOn()

            polydata = reader.GetOutput()
            polydata.SetSource(None)

            polydata_append.AddInput(polydata)
            del reader
            del polydata
            t -= 1

        polydata_append.Update()
        polydata_append.GetOutput().ReleaseDataFlagOn()
        polydata = polydata_append.GetOutput()
        #polydata.Register(None)
        polydata.SetSource(None)
        del polydata_append

        if algorithm == 'ca_smoothing':
            normals = vtk.vtkPolyDataNormals()
            normals_ref = weakref.ref(normals)
            normals_ref().AddObserver("ProgressEvent", lambda obj,evt:
                                      UpdateProgress(normals_ref(), _("Creating 3D surface...")))
            normals.SetInput(polydata)
            normals.ReleaseDataFlagOn()
            #normals.SetFeatureAngle(80)
            #normals.AutoOrientNormalsOn()
            normals.ComputeCellNormalsOn()
            normals.GetOutput().ReleaseDataFlagOn()
            normals.Update()
            del polydata
            polydata = normals.GetOutput()
            polydata.SetSource(None)
            del normals

            clean = vtk.vtkCleanPolyData()
            clean.ReleaseDataFlagOn()
            clean.GetOutput().ReleaseDataFlagOn()
            clean_ref = weakref.ref(clean)
            clean_ref().AddObserver("ProgressEvent", lambda obj,evt:
                            UpdateProgress(clean_ref(), _("Creating 3D surface...")))
            clean.SetInput(polydata)
            clean.PointMergingOn()
            clean.Update()

            del polydata
            polydata = clean.GetOutput()
            polydata.SetSource(None)
            del clean

            try:
                polydata.BuildLinks()
            except TypeError:
                polydata.BuildLinks(0)
            polydata = ca_smoothing.ca_smoothing(polydata, options['angle'],
                                                 options['max distance'],
                                                 options['min weight'],
                                                 options['steps'])
            polydata.SetSource(None)
            polydata.DebugOn()

        else:
            #smoother = vtk.vtkWindowedSincPolyDataFilter()
            smoother = vtk.vtkSmoothPolyDataFilter()
            smoother_ref = weakref.ref(smoother)
            smoother_ref().AddObserver("ProgressEvent", lambda obj,evt:
                            UpdateProgress(smoother_ref(), _("Creating 3D surface...")))
            smoother.SetInput(polydata)
            smoother.SetNumberOfIterations(smooth_iterations)
            smoother.SetRelaxationFactor(smooth_relaxation_factor)
            smoother.SetFeatureAngle(80)
            #smoother.SetEdgeAngle(90.0)
            #smoother.SetPassBand(0.1)
            smoother.BoundarySmoothingOn()
            smoother.FeatureEdgeSmoothingOn()
            #smoother.NormalizeCoordinatesOn()
            #smoother.NonManifoldSmoothingOn()
            smoother.ReleaseDataFlagOn()
            smoother.GetOutput().ReleaseDataFlagOn()
            smoother.Update()
            del polydata
            polydata = smoother.GetOutput()
            #polydata.Register(None)
            polydata.SetSource(None)
            del smoother


        if decimate_reduction:
            print "Decimating", decimate_reduction
            decimation = vtk.vtkQuadricDecimation()
            decimation.ReleaseDataFlagOn()
            decimation.SetInput(polydata)
            decimation.SetTargetReduction(decimate_reduction)
            decimation_ref = weakref.ref(decimation)
            decimation_ref().AddObserver("ProgressEvent", lambda obj,evt:
                            UpdateProgress(decimation_ref(), _("Creating 3D surface...")))
            #decimation.PreserveTopologyOn()
            #decimation.SplittingOff()
            #decimation.BoundaryVertexDeletionOff()
            decimation.GetOutput().ReleaseDataFlagOn()
            decimation.Update()
            del polydata
            polydata = decimation.GetOutput()
            #polydata.Register(None)
            polydata.SetSource(None)
            del decimation

        to_measure = polydata
        #to_measure.Register(None)
        to_measure.SetSource(None)

        if keep_largest:
            conn = vtk.vtkPolyDataConnectivityFilter()
            conn.SetInput(polydata)
            conn.SetExtractionModeToLargestRegion()
            conn_ref = weakref.ref(conn)
            conn_ref().AddObserver("ProgressEvent", lambda obj,evt:
                    UpdateProgress(conn_ref(), _("Creating 3D surface...")))
            conn.Update()
            conn.GetOutput().ReleaseDataFlagOn()
            del polydata
            polydata = conn.GetOutput()
            #polydata.Register(None)
            polydata.SetSource(None)
            del conn

        #Filter used to detect and fill holes. Only fill boundary edges holes.
        #TODO: Hey! This piece of code is the same from
        #polydata_utils.FillSurfaceHole, we need to review this.
        if fill_holes:
            filled_polydata = vtk.vtkFillHolesFilter()
            filled_polydata.ReleaseDataFlagOn()
            filled_polydata.SetInput(polydata)
            filled_polydata.SetHoleSize(300)
            filled_polydata_ref = weakref.ref(filled_polydata)
            filled_polydata_ref().AddObserver("ProgressEvent", lambda obj,evt:
                    UpdateProgress(filled_polydata_ref(), _("Creating 3D surface...")))
            filled_polydata.Update()
            filled_polydata.GetOutput().ReleaseDataFlagOn()
            del polydata
            polydata = filled_polydata.GetOutput()
            #polydata.Register(None)
            polydata.SetSource(None)
            polydata.DebugOn()
            del filled_polydata

        proj = prj.Project()

        normals = vtk.vtkPolyDataNormals()
        normals.ReleaseDataFlagOn()
        normals_ref = weakref.ref(normals)
        normals_ref().AddObserver("ProgressEvent", lambda obj,evt:
                        UpdateProgress(normals_ref(), _("Creating 3D surface...")))
        normals.SetInput(polydata)
        normals.SetFeatureAngle(80)
        normals.AutoOrientNormalsOn()
        normals.GetOutput().ReleaseDataFlagOn()
        normals.Update()
        del polydata
        polydata = normals.GetOutput()
        #polydata.Register(None)
        polydata.SetSource(None)
        del normals

        # Improve performance
        stripper = vtk.vtkStripper()
        stripper.ReleaseDataFlagOn()
        stripper_ref = weakref.ref(stripper)
        stripper_ref().AddObserver("ProgressEvent", lambda obj,evt:
                        UpdateProgress(stripper_ref(), _("Creating 3D surface...")))
        stripper.SetInput(polydata)
        stripper.PassThroughCellIdsOn()
        stripper.PassThroughPointIdsOn()
        stripper.GetOutput().ReleaseDataFlagOn()
        stripper.Update()
        del polydata
        polydata = stripper.GetOutput()
        #polydata.Register(None)
        polydata.SetSource(None)
        del stripper

        # Map polygonal data (vtkPolyData) to graphics primitives.
        mapper = vtk.vtkPolyDataMapper()
        mapper.SetInput(polydata)
        mapper.ScalarVisibilityOff()
        mapper.ReleaseDataFlagOn()
        mapper.ImmediateModeRenderingOn() # improve performance

        # Represent an object (geometry & properties) in the rendered scene
        actor = vtk.vtkActor()
        actor.SetMapper(mapper)
        del mapper
        #Create Surface instance
        if overwrite:
            surface = Surface(index = self.last_surface_index)
        else:
            surface = Surface(name=surface_name)

        wdir = proj.working_dir
        temp_file = tempfile.mktemp(prefix='surface%d_' % surface.index, suffix='.vtp', dir=wdir)

        writer = vtk.vtkXMLPolyDataWriter()
        writer.SetInput(polydata)
        writer.SetFileName(temp_file)
        writer.Write()
        del writer

        surface.temp_file = temp_file
        surface.colour = colour
        surface.polydata = polydata
        del polydata

        # Set actor colour and transparency
        actor.GetProperty().SetColor(colour)
        actor.GetProperty().SetOpacity(1-surface.transparency)

        prop = actor.GetProperty()

        interpolation = int(ses.Session().surface_interpolation)

        prop.SetInterpolation(interpolation)

        if overwrite:
            proj.ChangeSurface(surface)
        else:
            index = proj.AddSurface(surface)
            surface.index = index
            self.last_surface_index = index

        session = ses.Session()
        session.ChangeProject()

        # The following lines have to be here, otherwise all volumes disappear
        measured_polydata = vtk.vtkMassProperties()
        measured_polydata.ReleaseDataFlagOn()
        measured_polydata.SetInput(to_measure)
        volume =  float(measured_polydata.GetVolume())
        surface.volume = volume
        self.last_surface_index = surface.index
        del measured_polydata
        del to_measure

        Publisher.sendMessage('Load surface actor into viewer', actor)

        # Send actor by pubsub to viewer's render
        if overwrite and self.actors_dict.keys():
            old_actor = self.actors_dict[self.last_surface_index]
            Publisher.sendMessage('Remove surface actor from viewer', old_actor)

        # Save actor for future management tasks
        self.actors_dict[surface.index] = actor

        Publisher.sendMessage('Update surface info in GUI',
                                    (surface.index, surface.name,
                                    surface.colour, surface.volume,
                                    surface.transparency))

        #When you finalize the progress. The bar is cleaned.
        UpdateProgress = vu.ShowProgress(1)
        UpdateProgress(0, _("Ready"))
        Publisher.sendMessage('Update status text in GUI', _("Ready"))

        Publisher.sendMessage('End busy cursor')
        del actor

    def UpdateSurfaceInterpolation(self, pub_evt):
        interpolation = int(ses.Session().surface_interpolation)
        key_actors = self.actors_dict.keys()

        for key in self.actors_dict:
            self.actors_dict[key].GetProperty().SetInterpolation(interpolation)
        Publisher.sendMessage('Render volume viewer')

    def RemoveActor(self, index):
        """
        Remove actor, according to given actor index.
        """
        Publisher.sendMessage('Remove surface actor from viewer', (index))
        self.actors_dict.pop(index)
        # Remove surface from project's surface_dict
        proj = prj.Project()
        proj.surface_dict.pop(index)

    def OnChangeSurfaceName(self, pubsub_evt):
        index, name = pubsub_evt.data
        proj = prj.Project()
        proj.surface_dict[index].name = name

    def OnShowSurface(self, pubsub_evt):
        index, value = pubsub_evt.data
        self.ShowActor(index, value)

    def ShowActor(self, index, value):
        """
        Show or hide actor, according to given actor index and value.
        """
        self.actors_dict[index].SetVisibility(value)
        # Update value in project's surface_dict
        proj = prj.Project()
        proj.surface_dict[index].is_shown = value
        Publisher.sendMessage('Render volume viewer')

    def SetActorTransparency(self, pubsub_evt):
        """
        Set actor transparency (oposite to opacity) according to given actor
        index and value.
        """
        index, value = pubsub_evt.data
        self.actors_dict[index].GetProperty().SetOpacity(1-value)
        # Update value in project's surface_dict
        proj = prj.Project()
        proj.surface_dict[index].transparency = value
        Publisher.sendMessage('Render volume viewer')

    def SetActorColour(self, pubsub_evt):
        """
        """
        index, colour = pubsub_evt.data
        self.actors_dict[index].GetProperty().SetColor(colour)
        # Update value in project's surface_dict
        proj = prj.Project()
        proj.surface_dict[index].colour = colour
        Publisher.sendMessage('Render volume viewer')

    def OnExportSurface(self, pubsub_evt):
        filename, filetype = pubsub_evt.data
        if (filetype == const.FILETYPE_STL) or\
           (filetype == const.FILETYPE_VTP) or\
           (filetype == const.FILETYPE_PLY) or\
           (filetype == const.FILETYPE_STL_ASCII):

            # First we identify all surfaces that are selected
            # (if any)
            proj = prj.Project()
            polydata_list = []

            for index in proj.surface_dict:
                surface = proj.surface_dict[index]
                if surface.is_shown:
                    polydata_list.append(surface.polydata)

            if len(polydata_list) == 0:
                utl.debug("oops - no polydata")
                return
            elif len(polydata_list) == 1:
                polydata = polydata_list[0]
            else:
                polydata = pu.Merge(polydata_list)

            # Having a polydata that represents all surfaces
            # selected, we write it, according to filetype
            if filetype == const.FILETYPE_STL:
                writer = vtk.vtkSTLWriter()
                writer.SetFileTypeToBinary()
            elif filetype == const.FILETYPE_STL_ASCII:
                writer = vtk.vtkSTLWriter()
                writer.SetFileTypeToASCII()
            elif filetype == const.FILETYPE_VTP:
                writer = vtk.vtkXMLPolyDataWriter()
            #elif filetype == const.FILETYPE_IV:
            #    writer = vtk.vtkIVWriter()
            elif filetype == const.FILETYPE_PLY:
                writer = vtk.vtkPLYWriter()
                writer.SetFileTypeToASCII()
                writer.SetColorModeToOff()
                #writer.SetDataByteOrderToLittleEndian()
                #writer.SetColorModeToUniformCellColor()
                #writer.SetColor(255, 0, 0)

            if filetype in (const.FILETYPE_STL, const.FILETYPE_PLY):
                # Invert normals
                normals = vtk.vtkPolyDataNormals()
                normals.SetInput(polydata)
                normals.SetFeatureAngle(80)
                normals.AutoOrientNormalsOn()
                normals.GetOutput().ReleaseDataFlagOn()
                normals.UpdateInformation()
                polydata = normals.GetOutput()

            filename = filename.encode(wx.GetDefaultPyEncoding())
            writer.SetFileName(filename)
            writer.SetInput(polydata)
            writer.Write()