Fix line placement of markers on points (#1548)

REFS #1604,#1350,#1607,#1548,#1625

include/mapnik/grid/grid_marker_helpers.hpp

@@ -78,11 +78,17 @@ struct raster_markers_rasterizer_dispatch_grid
     {
         marker_placement_e placement_method = sym_.get_marker_placement();
         box2d<double> bbox_(0,0, src_.width(),src_.height());
-        if (placement_method != MARKER_LINE_PLACEMENT)
+        if (placement_method != MARKER_LINE_PLACEMENT ||
+            path.type() == Point)
         {
             double x = 0;
             double y = 0;
-            if (placement_method == MARKER_INTERIOR_PLACEMENT)
+            if (path.type() == LineString)
+            {
+                if (!label::middle_point(path, x, y))
+                    return;
+            }
+            else if (placement_method == MARKER_INTERIOR_PLACEMENT)
             {
                 if (!label::interior_position(path, x, y))
                     return;
@@ -209,11 +215,17 @@ struct vector_markers_rasterizer_dispatch_grid
     void add_path(T & path)
     {
         marker_placement_e placement_method = sym_.get_marker_placement();
-        if (placement_method != MARKER_LINE_PLACEMENT)
+        if (placement_method != MARKER_LINE_PLACEMENT ||
+            path.type() == Point)
         {
             double x = 0;
             double y = 0;
-            if (placement_method == MARKER_INTERIOR_PLACEMENT)
+            if (path.type() == LineString)
+            {
+                if (!label::middle_point(path, x, y))
+                    return;
+            }
+            else if (placement_method == MARKER_INTERIOR_PLACEMENT)
             {
                 if (!label::interior_position(path, x, y))
                     return;

include/mapnik/marker_helpers.hpp

@@ -87,7 +87,8 @@ struct vector_markers_rasterizer_dispatch
     {
         marker_placement_e placement_method = sym_.get_marker_placement();
 
-        if (placement_method != MARKER_LINE_PLACEMENT)
+        if (placement_method != MARKER_LINE_PLACEMENT ||
+            path.type() == Point)
         {
             double x = 0;
             double y = 0;
@@ -188,7 +189,8 @@ struct raster_markers_rasterizer_dispatch
         marker_placement_e placement_method = sym_.get_marker_placement();
         box2d<double> bbox_(0,0, src_.width(),src_.height());
 
-        if (placement_method != MARKER_LINE_PLACEMENT)
+        if (placement_method != MARKER_LINE_PLACEMENT ||
+            path.type() == Point)
         {
             double x = 0;
             double y = 0;

src/cairo_renderer.cpp

@@ -1494,11 +1494,17 @@ struct markers_dispatch
     {
         marker_placement_e placement_method = sym_.get_marker_placement();
 
-        if (placement_method != MARKER_LINE_PLACEMENT)
+        if (placement_method != MARKER_LINE_PLACEMENT ||
+            path.type() == Point)
         {
             double x = 0;
             double y = 0;
-            if (placement_method == MARKER_INTERIOR_PLACEMENT)
+            if (path.type() == LineString)
+            {
+                if (!label::middle_point(path, x, y))
+                    return;
+            }
+            else if (placement_method == MARKER_INTERIOR_PLACEMENT)
             {
                 if (!label::interior_position(path, x, y))
                     return;
@@ -1577,11 +1583,17 @@ struct markers_dispatch_2
     {
         marker_placement_e placement_method = sym_.get_marker_placement();
 
-        if (placement_method != MARKER_LINE_PLACEMENT)
+        if (placement_method != MARKER_LINE_PLACEMENT ||
+            path.type() == Point)
         {
             double x = 0;
             double y = 0;
-            if (placement_method == MARKER_INTERIOR_PLACEMENT)
+            if (path.type() == LineString)
+            {
+                if (!label::middle_point(path, x, y))
+                    return;
+            }
+            else if (placement_method == MARKER_INTERIOR_PLACEMENT)
             {
                 if (!label::interior_position(path, x, y))
                     return;

tests/visual_tests/styles/marker_line_placement_on_points.xml

@@ -0,0 +1,36 @@
+<!DOCTYPE Map>
+<Map background-color="white" srs="+init=epsg:4326" minimum-version="0.7.2">
+
+    <Style name="1">
+        <Rule>
+          <Filter>[id]=1</Filter>
+          <MarkersSymbolizer fill="darkgreen" opacity=".7" width="15" height="10" stroke="green" stroke-width="7" stroke-opacity=".2" placement="line" marker-type="ellipse"/>
+        </Rule>
+        <Rule>
+          <Filter>[id]=2</Filter>
+             <MarkersSymbolizer fill="darkorange" opacity=".7" width="20" height="10" stroke="orange" stroke-width="7" stroke-opacity=".2" placement="line" marker-type="ellipse"/>
+        </Rule>
+        <Rule>
+          <Filter>[id]=3</Filter>
+             <MarkersSymbolizer fill="darkred" opacity=".7" width="20" height="10" stroke="orange" stroke-width="7" stroke-opacity=".2" placement="line" marker-type="ellipse"/>
+        </Rule>
+    </Style>
+    <Layer name="point" srs="+init=epsg:4326">
+        <StyleName>1</StyleName>
+        <Datasource>
+            <Parameter name="type">csv</Parameter>
+            <Parameter name="inline">
+            x,y,id
+            0,0,1
+            5,0,1
+            5,5,1
+            0,5,1
+            2.5,2.5,2
+            2.5,3,3
+            2.5,2,3
+            3,2.5,3
+            2,2.5,3
+            </Parameter>
+        </Datasource>
+    </Layer>
+</Map>

tests/visual_tests/test.py

@@ -31,6 +31,8 @@ files = [
         'bbox': mapnik.Box2d(0, 0, 190, 180)},
     {'name': "marker-on-line", 'sizes':[(600,400)],
         'bbox': mapnik.Box2d(-10, 0, 15, 20)},
+    {'name': "marker_line_placement_on_points", 'sizes':[(500,100)],
+        'bbox': mapnik.Box2d(0, 0, 5, 5)},
     {'name': "whole-centroid", 'sizes':[(600,400)],
         'bbox': mapnik.Box2d(736908, 4390316, 2060771, 5942346)},
     {'name': "simple-E"},