Add repeat-distance to text symbolizer properties.

Update collision detector to handle minimum-distance and repeat-distance seperately.
Update placement_finder to use repeat-distance.
Update group symbolizer to handle minimum-distance and repeat-distance.

bindings/python/mapnik_text_placement.cpp

@@ -424,6 +424,7 @@ void export_text_placement()
         .def_readwrite("label_position_tolerance", &text_symbolizer_properties::label_position_tolerance)
         .def_readwrite("avoid_edges", &text_symbolizer_properties::avoid_edges)
         .def_readwrite("minimum_distance", &text_symbolizer_properties::minimum_distance)
+        .def_readwrite("repeat_distance", &text_symbolizer_properties::repeat_distance)
         .def_readwrite("minimum_padding", &text_symbolizer_properties::minimum_padding)
         .def_readwrite("minimum_path_length", &text_symbolizer_properties::minimum_path_length)
         .def_readwrite("maximum_angle_char_delta", &text_symbolizer_properties::max_char_angle_delta)

include/mapnik/label_collision_detector.hpp

@@ -158,29 +158,47 @@ public:
         return true;
     }
 
-    bool has_placement(box2d<double> const& box, mapnik::value_unicode_string const& text, double distance)
+    bool has_placement(box2d<double> const& box, double minimum_distance)
     {
-        box2d<double> bigger_box(box.minx() - distance, box.miny() - distance, box.maxx() + distance, box.maxy() + distance);
+        box2d<double> const& minimum_box = (minimum_distance > 0
-        tree_t::query_iterator itr = tree_.query_in_box(bigger_box);
+                                               ? box2d<double>(box.minx() - minimum_distance, box.miny() - minimum_distance,
+                                                               box.maxx() + minimum_distance, box.maxy() + minimum_distance)
+                                               : box);
+
+        tree_t::query_iterator itr = tree_.query_in_box(minimum_box);
         tree_t::query_iterator end = tree_.query_end();
 
         for (;itr != end; ++itr)
         {
-            if (itr->box.intersects(box) || (text == itr->text && itr->box.intersects(bigger_box)))
+            if (itr->box.intersects(minimum_box))
+            {
                 return false;
+            }
         }
         return true;
     }
 
-    bool has_point_placement(box2d<double> const& box, double distance)
+    bool has_placement(box2d<double> const& box, double minimum_distance, mapnik::value_unicode_string const& text, double repeat_distance)
     {
-        box2d<double> bigger_box(box.minx() - distance, box.miny() - distance, box.maxx() + distance, box.maxy() + distance);
+        box2d<double> const& minimum_box = (minimum_distance > 0
-        tree_t::query_iterator itr = tree_.query_in_box(bigger_box);
+                                               ? box2d<double>(box.minx() - minimum_distance, box.miny() - minimum_distance,
+                                                               box.maxx() + minimum_distance, box.maxy() + minimum_distance)
+                                               : box);
+
+        box2d<double> const& repeat_box = (repeat_distance > 0
+                                               ? box2d<double>(box.minx() - repeat_distance, box.miny() - repeat_distance,
+                                                               box.maxx() + repeat_distance, box.maxy() + repeat_distance)
+                                               : box);
+
+        tree_t::query_iterator itr = tree_.query_in_box(repeat_distance > minimum_distance ? repeat_box : minimum_box);
         tree_t::query_iterator end = tree_.query_end();
 
         for ( ;itr != end; ++itr)
         {
-            if (itr->box.intersects(bigger_box)) return false;
+            if (itr->box.intersects(minimum_box) || (text == itr->text && itr->box.intersects(repeat_box)))
+            {
+                return false;
+            }
         }
 
         return true;

include/mapnik/renderer_common/process_group_symbolizer.hpp

@@ -297,38 +297,28 @@ void render_group_symbolizer(group_symbolizer const& sym,
                                    common.scale_factor_, common.t_,
                                    *common.detector_, clipping_extent);
 
-    // determine if we should be tracking repeat distance
-    bool check_repeat = (helper.get_properties().minimum_distance > 0);
-
     for (size_t i = 0; i < matches.size(); ++i)
     {
-        if (check_repeat)
+        group_rule_ptr match_rule = matches[i].first;
+        feature_ptr match_feature = matches[i].second;
+        value_unicode_string rpt_key_value = "";
+
+        // get repeat key from matched group rule
+        expression_ptr rpt_key_expr = match_rule->get_repeat_key();
+
+        // if no repeat key was defined, use default from group symbolizer
+        if (!rpt_key_expr)
         {
-            group_rule_ptr match_rule = matches[i].first;
+            rpt_key_expr = get<expression_ptr>(sym, keys::repeat_key);
-            feature_ptr match_feature = matches[i].second;
-            value_unicode_string rpt_key_value = "";
-
-            // get repeat key from matched group rule
-            expression_ptr rpt_key_expr = match_rule->get_repeat_key();
-
-            // if no repeat key was defined, use default from group symbolizer
-            if (!rpt_key_expr)
-            {
-                rpt_key_expr = get<expression_ptr>(sym, keys::repeat_key);
-            }
-
-            // evalute the repeat key with the matched sub feature if we have one
-            if (rpt_key_expr)
-            {
-                rpt_key_value = boost::apply_visitor(evaluate<Feature,value_type,attributes>(*match_feature,common.vars_),
-                                                     *rpt_key_expr).to_unicode();
-            }
-            helper.add_box_element(layout_manager.offset_box_at(i), rpt_key_value);
         }
-        else
+
+        // evalute the repeat key with the matched sub feature if we have one
+        if (rpt_key_expr)
         {
-            helper.add_box_element(layout_manager.offset_box_at(i));
+            rpt_key_value = boost::apply_visitor(evaluate<Feature,value_type,attributes>(*match_feature,common.vars_),
+                                                 *rpt_key_expr).to_unicode();
         }
+        helper.add_box_element(layout_manager.offset_box_at(i), rpt_key_value);
     }
 
     pixel_position_list positions = helper.get();

include/mapnik/text/placement_finder.hpp

@@ -72,7 +72,7 @@ private:
     // Adjusts user defined spacing to place an integer number of labels.
     double get_spacing(double path_length, double layout_width) const;
     // Checks for collision.
-    bool collision(box2d<double> const& box) const;
+    bool collision(box2d<double> const& box, const value_unicode_string &repeat_key = "") const;
     // Adds marker to glyph_positions and to collision detector. Returns false if there is a collision.
     bool add_marker(glyph_positions_ptr glyphs, pixel_position const& pos) const;
     // Maps upright==auto, left_only and right_only to left,right to simplify processing.

include/mapnik/text/text_properties.hpp

@@ -128,6 +128,7 @@ struct text_properties_expressions
     symbolizer_base::value_type label_spacing = 0.0;
     symbolizer_base::value_type label_position_tolerance = 0.0;
     symbolizer_base::value_type avoid_edges = false;
+    symbolizer_base::value_type repeat_distance = 0.0;
     symbolizer_base::value_type minimum_distance = 0.0;
     symbolizer_base::value_type minimum_padding = 0.0;
     symbolizer_base::value_type minimum_path_length = 0.0;
@@ -170,6 +171,7 @@ struct MAPNIK_DECL text_symbolizer_properties
     // distance the label can be moved on the line to fit, if 0 the default is used
     double label_position_tolerance;
     bool avoid_edges;
+    double repeat_distance;
     double minimum_distance;
     double minimum_padding;
     double minimum_path_length;

src/group/group_symbolizer_helper.cpp

@@ -164,9 +164,10 @@ bool group_symbolizer_helper::collision(const box2d<double> &box, const value_un
          !query_extent_.contains(box + (scale_factor_ * placement_->properties.minimum_padding)))
             ||
         (!placement_->properties.allow_overlap &&
-            ((repeat_key.length() == 0 && !detector_.has_point_placement(box, placement_->properties.minimum_distance * scale_factor_))
+            ((repeat_key.length() == 0 && !detector_.has_placement(box, placement_->properties.minimum_distance * scale_factor_))
                 ||
-             (repeat_key.length() > 0  && !detector_.has_placement(box, repeat_key, placement_->properties.minimum_distance * scale_factor_))))
+             (repeat_key.length() > 0  && !detector_.has_placement(box, placement_->properties.minimum_distance * scale_factor_,
+                                                                   repeat_key, placement_->properties.repeat_distance * scale_factor_))))
         )
     {
         return true;

src/text/placement_finder.cpp

@@ -120,8 +120,8 @@ bool placement_finder::find_point_placement(pixel_position const& pos)
         box2d<double> bbox = layout.bounds();
         bbox.re_center(layout_center.x, layout_center.y);
 
-        // For point placements it is faster to just check the bounding box.
+        /* For point placements it is faster to just check the bounding box. */
-        if (collision(bbox)) return false;
+        if (collision(bbox, layouts_.text())) return false;
 
         if (layout.num_lines()) bboxes.push_back(std::move(bbox));
 
@@ -309,7 +309,7 @@ bool placement_finder::single_line_placement(vertex_cache &pp, text_upright_e or
                 cluster_offset.y -= rot.sin * glyph.advance();
 
                 box2d<double> bbox = get_bbox(layout, glyph, pos, rot);
-                if (collision(bbox)) return false;
+                if (collision(bbox, layouts_.text())) return false;
                 bboxes.push_back(std::move(bbox));
                 glyphs->push_back(glyph, pos, rot);
             }
@@ -376,7 +376,7 @@ double placement_finder::get_spacing(double path_length, double layout_width) co
     return path_length / num_labels;
 }
 
-bool placement_finder::collision(const box2d<double> &box) const
+bool placement_finder::collision(const box2d<double> &box, const value_unicode_string &repeat_key) const
 {
     if (!detector_.extent().intersects(box)
             ||
@@ -386,7 +386,10 @@ bool placement_finder::collision(const box2d<double> &box) const
          !extent_.contains(box + (scale_factor_ * info_.properties.minimum_padding)))
             ||
         (!info_.properties.allow_overlap &&
-         !detector_.has_point_placement(box, info_.properties.minimum_distance * scale_factor_))
+            ((repeat_key.length() == 0 && !detector_.has_placement(box, info_.properties.minimum_distance * scale_factor_))
+                ||
+             (repeat_key.length() > 0  && !detector_.has_placement(box, info_.properties.minimum_distance * scale_factor_,
+                                                                   repeat_key, info_.properties.repeat_distance * scale_factor_))))
         )
     {
         return true;
@@ -410,7 +413,7 @@ bool placement_finder::add_marker(glyph_positions_ptr glyphs, pixel_position con
     box2d<double> bbox = marker_box_;
     bbox.move(real_pos.x, real_pos.y);
     glyphs->set_marker(marker_, real_pos);
-    if (collision(bbox)) return false;
+    if (collision(bbox, layouts_.text())) return false;
     detector_.insert(bbox);
     return true;
 }

src/text/text_properties.cpp

@@ -44,6 +44,7 @@ text_symbolizer_properties::text_symbolizer_properties()
       label_spacing(0.0),
       label_position_tolerance(0.0),
       avoid_edges(false),
+      repeat_distance(0.0),
       minimum_distance(0.0),
       minimum_padding(0.0),
       minimum_path_length(0.0),
@@ -62,6 +63,7 @@ void text_symbolizer_properties::evaluate_text_properties(feature_impl const& fe
     label_spacing = boost::apply_visitor(extract_value<value_double>(feature,attrs), expressions.label_spacing);
     label_position_tolerance = boost::apply_visitor(extract_value<value_double>(feature,attrs), expressions.label_position_tolerance);
     avoid_edges = boost::apply_visitor(extract_value<value_bool>(feature,attrs), expressions.avoid_edges);
+    repeat_distance = boost::apply_visitor(extract_value<value_double>(feature,attrs), expressions.repeat_distance);
     minimum_distance = boost::apply_visitor(extract_value<value_double>(feature,attrs), expressions.minimum_distance);
     minimum_padding = boost::apply_visitor(extract_value<value_double>(feature,attrs), expressions.minimum_padding);
     minimum_path_length = boost::apply_visitor(extract_value<value_double>(feature,attrs), expressions.minimum_path_length);
@@ -117,6 +119,7 @@ void text_symbolizer_properties::text_properties_from_xml(xml_node const& node)
     set_property_from_xml<label_placement_e>(expressions.label_placement, "placement", node);
     set_property_from_xml<value_double>(expressions.label_spacing, "spacing", node);
     set_property_from_xml<value_double>(expressions.label_position_tolerance, "label-position-tolerance", node);
+    set_property_from_xml<value_double>(expressions.repeat_distance, "repeat-distance", node);
     set_property_from_xml<value_double>(expressions.minimum_distance, "minimum-distance", node);
     set_property_from_xml<value_double>(expressions.minimum_padding, "minimum-padding", node);
     set_property_from_xml<value_double>(expressions.minimum_path_length, "minimum-path-length", node);
@@ -159,6 +162,10 @@ void text_symbolizer_properties::to_xml(boost::property_tree::ptree &node,
     {
         serialize_property("spacing", expressions.label_spacing, node);
     }
+    if (!(expressions.repeat_distance == dfl.expressions.repeat_distance) || explicit_defaults)
+    {
+        serialize_property("repeat-distance", expressions.repeat_distance, node);
+    }
     if (!(expressions.minimum_distance == dfl.expressions.minimum_distance) || explicit_defaults)
     {
         serialize_property("minimum-distance", expressions.minimum_distance, node);

tests/visual_tests/styles/group-symbolizer-line-1.xml

@@ -17,7 +17,7 @@ wkt,name1,ref1,name2,ref2
   <Style name="alpha">
     <Rule>
       <LineSymbolizer stroke-width="0.2" stroke="#ff0000"/>
-      <GroupSymbolizer start-column="1" num-columns="2" placement="line" avoid-edges="false" minimum-distance="50" spacing="100" repeat-key="[name%]+'-'+[ref%]">
+      <GroupSymbolizer start-column="1" num-columns="2" placement="line" avoid-edges="false" repeat-distance="50" spacing="100" repeat-key="[name%]+'-'+[ref%]">
         <PairLayout item-margin="1"/>
         <GroupRule>
           <ShieldSymbolizer file="../../data/svg/rect.svg" face-name="DejaVu Sans Book" size="16" placement="point">
@@ -43,7 +43,7 @@ wkt,name1,ref1,name2,ref2
   <Style name="beta">
     <Rule>
       <LineSymbolizer stroke-width="0.2" stroke="#ff0000"/>
-      <GroupSymbolizer start-column="1" num-columns="2" placement="line" avoid-edges="false" minimum-distance="40" spacing="80" repeat-key="[name%]+'-'+[ref%]">
+      <GroupSymbolizer start-column="1" num-columns="2" placement="line" avoid-edges="false" repeat-distance="40" spacing="80" repeat-key="[name%]+'-'+[ref%]">
         <PairLayout item-margin="1"/>
         <GroupRule>
           <ShieldSymbolizer file="../../data/svg/rect.svg" face-name="DejaVu Sans Book" size="16" placement="point">
@@ -69,7 +69,7 @@ wkt,name1,ref1,name2,ref2
   <Style name="gamma">
     <Rule>
       <LineSymbolizer stroke-width="0.2" stroke="#ff0000"/>
-      <GroupSymbolizer start-column="1" num-columns="2" placement="line" avoid-edges="false" minimum-distance="30" spacing="60" repeat-key="[name%]+'-'+[ref%]">
+      <GroupSymbolizer start-column="1" num-columns="2" placement="line" avoid-edges="false" repeat-distance="30" spacing="60" repeat-key="[name%]+'-'+[ref%]">
         <PairLayout item-margin="1"/>
         <GroupRule>
           <ShieldSymbolizer file="../../data/svg/rect.svg" face-name="DejaVu Sans Book" size="16" placement="point">

tests/visual_tests/styles/group-symbolizer-line-2.xml

@@ -22,10 +22,10 @@ wkt,key1,key2
   <Style name="alpha">
     <Rule>
       <PointSymbolizer ignore-placement="true"/>
-      <GroupSymbolizer start-column="1" num-columns="1" placement="point" avoid-edges="false" minimum-distance="1" spacing="1" repeat-key="[key%]">
+      <GroupSymbolizer start-column="1" num-columns="1" placement="point" avoid-edges="false" repeat-key="[key%]">
         <PairLayout item-margin="1"/>
         <GroupRule>
-          <ShieldSymbolizer file="../../data/svg/rect.svg" face-name="DejaVu Sans Book" size="10" placement="point" dy="0" fill="#ff0000">[key%]</ShieldSymbolizer>
+          <ShieldSymbolizer file="../../data/svg/rect.svg" face-name="DejaVu Sans Book" size="10" minimum-distance="1" placement="point" dy="0" fill="#ff0000">[key%]</ShieldSymbolizer>
         </GroupRule>
       </GroupSymbolizer>
     </Rule>
@@ -47,7 +47,7 @@ wkt,name1,ref1,name2,ref2
 
   <Style name="beta">
     <Rule>
-      <GroupSymbolizer start-column="1" num-columns="1" placement="line" avoid-edges="false" minimum-distance="20" spacing="1" repeat-key="bar">
+      <GroupSymbolizer start-column="1" num-columns="1" placement="line" avoid-edges="false" repeat-distance="20" spacing="1" repeat-key="bar">
         <PairLayout item-margin="1"/>
         <GroupRule>
           <ShieldSymbolizer file="../../data/svg/rect.svg" face-name="DejaVu Sans Book" size="10" placement="point" dy="0" fill="#ffffff">bar</ShieldSymbolizer>
@@ -72,7 +72,7 @@ wkt,name1,ref1,name2,ref2
 
   <Style name="gamma">
     <Rule>
-      <GroupSymbolizer start-column="1" num-columns="1" placement="line" avoid-edges="false" minimum-distance="20" spacing="1" repeat-key="foo">
+      <GroupSymbolizer start-column="1" num-columns="1" placement="line" avoid-edges="false" repeat-distance="20" spacing="1" repeat-key="foo">
         <PairLayout item-margin="1"/>
         <GroupRule>
           <ShieldSymbolizer file="../../data/svg/rect.svg" face-name="DejaVu Sans Book" size="10" placement="point" dy="0" fill="#000000">foo</ShieldSymbolizer>