static  boost::python::tuple
 getstate(const text_symbolizer& t)
 {
     boost::python::list disp = get_displacement_list(t);
     boost::python::list anchor = get_anchor_list(t);
     
     // so we do not exceed max args accepted by make_tuple,
     // lets put the increasing list of parameters in a list
     boost::python::list extras;
     extras.append(t.get_wrap_char_string());
     extras.append(t.get_line_spacing());
     extras.append(t.get_character_spacing());
     extras.append(t.get_text_convert());
     extras.append(t.get_wrap_before());
     extras.append(t.get_horizontal_alignment());
     extras.append(t.get_justify_alignment());
     extras.append(t.get_text_opacity());
             
     return boost::python::make_tuple(disp,t.get_label_placement(),
                                      t.get_vertical_alignment(),t.get_halo_radius(),t.get_halo_fill(),t.get_text_ratio(),
                                      t.get_wrap_width(),t.get_label_spacing(),t.get_minimum_distance(),t.get_allow_overlap(),
                                      anchor,t.get_force_odd_labels(),t.get_max_char_angle_delta(),extras
         );
 }
void grid_renderer<T>::process(text_symbolizer const& sym,
                              Feature const& feature,
                              proj_transform const& prj_trans)
{
    typedef  coord_transform2<CoordTransform,geometry_type> path_type;

    bool placement_found = false;
    text_placement_info_ptr placement_options = sym.get_placement_options()->get_placement_info();
    while (!placement_found && placement_options->next())
    {
        expression_ptr name_expr = sym.get_name();
        if (!name_expr) return;
        value_type result = boost::apply_visitor(evaluate<Feature,value_type>(feature),*name_expr);
        UnicodeString text = result.to_unicode();

        if ( sym.get_text_transform() == UPPERCASE)
        {
            text = text.toUpper();
        }
        else if ( sym.get_text_transform() == LOWERCASE)
        {
            text = text.toLower();
        }
        else if ( sym.get_text_transform() == CAPITALIZE)
        {
            text = text.toTitle(NULL);
        }

        if ( text.length() <= 0 ) continue;
        color const& fill = sym.get_fill();

        face_set_ptr faces;

        if (sym.get_fontset().size() > 0)
        {
            faces = font_manager_.get_face_set(sym.get_fontset());
        }
        else
        {
            faces = font_manager_.get_face_set(sym.get_face_name());
        }

        stroker_ptr strk = font_manager_.get_stroker();
        if (!(faces->size() > 0 && strk))
        {
            throw config_error("Unable to find specified font face '" + sym.get_face_name() + "'");
        }
        text_renderer<T> ren(pixmap_, faces, *strk);
        ren.set_pixel_size(placement_options->text_size * (scale_factor_ * (1.0/pixmap_.get_resolution())));
        ren.set_fill(fill);
        ren.set_halo_fill(sym.get_halo_fill());
        ren.set_halo_radius(sym.get_halo_radius() * scale_factor_);
        ren.set_opacity(sym.get_text_opacity());

        // /pixmap_.get_resolution() ?
        box2d<double> dims(0,0,width_,height_);
        placement_finder<label_collision_detector4> finder(detector_,dims);

        string_info info(text);

        faces->get_string_info(info);
        unsigned num_geom = feature.num_geometries();
        for (unsigned i=0; i<num_geom; ++i)
        {
            geometry_type const& geom = feature.get_geometry(i);
            if (geom.num_points() == 0) continue; // don't bother with empty geometries
            while (!placement_found && placement_options->next_position_only())
            {
                placement text_placement(info, sym, scale_factor_);
                text_placement.avoid_edges = sym.get_avoid_edges();
                if (sym.get_label_placement() == POINT_PLACEMENT ||
                        sym.get_label_placement() == INTERIOR_PLACEMENT)
                {
                    double label_x, label_y, z=0.0;
                    if (sym.get_label_placement() == POINT_PLACEMENT)
                        geom.label_position(&label_x, &label_y);
                    else
                        geom.label_interior_position(&label_x, &label_y);
                    prj_trans.backward(label_x,label_y, z);
                    t_.forward(&label_x,&label_y);

                    double angle = 0.0;
                    expression_ptr angle_expr = sym.get_orientation();
                    if (angle_expr)
                    {
                        // apply rotation
                        value_type result = boost::apply_visitor(evaluate<Feature,value_type>(feature),*angle_expr);
                        angle = result.to_double();
                    }

                    finder.find_point_placement(text_placement, placement_options,
                                                label_x, label_y,
                                                angle, sym.get_line_spacing(),
                                                sym.get_character_spacing());

                    finder.update_detector(text_placement);
                }
                else if ( geom.num_points() > 1 && sym.get_label_placement() == LINE_PLACEMENT)
                {
                    path_type path(t_,geom,prj_trans);
                    finder.find_line_placements<path_type>(text_placement, placement_options, path);
                }

                if (!text_placement.placements.size()) continue;
                placement_found = true;

                for (unsigned int ii = 0; ii < text_placement.placements.size(); ++ii)
                {
                    double x = text_placement.placements[ii].starting_x;
                    double y = text_placement.placements[ii].starting_y;
                    ren.prepare_glyphs(&text_placement.placements[ii]);
                    ren.render_id(feature.id(),x,y,2);
                }
            }
        }
    }
    if (placement_found)
        pixmap_.add_feature(feature);
}