diff --git a/src/grid/process_markers_symbolizer.cpp b/src/grid/process_markers_symbolizer.cpp
index 823bad284..91d120dc7 100644
--- a/src/grid/process_markers_symbolizer.cpp
+++ b/src/grid/process_markers_symbolizer.cpp
@@ -24,22 +24,15 @@
 
 porting notes -->
 
- - grid includes
- - detector
+ - rasterizer -> grid_rasterizer
+ - current_buffer_ -> pixmap_
+ - agg::rendering_buffer -> grid_renderering_buffer
  - no gamma
  - mapnik::pixfmt_gray32
  - agg::scanline_bin sl
  - grid_rendering_buffer
  - agg::renderer_scanline_bin_solid
- - clamping:
-    // - clamp sizes to > 4 pixels of interactivity
-    if (tr.scale() < 0.5)
-    {
-        agg::trans_affine tr2;
-        tr2 *= agg::trans_affine_scaling(0.5);
-        tr = tr2;
-    }
-    tr *= agg::trans_affine_scaling(scale_factor_*(1.0/pixmap_.get_resolution()));
+ - TODO - clamp sizes to > 4 pixels of interactivity
  - svg_renderer.render_id
  - only encode feature if placements are found:
     if (placed)
@@ -55,6 +48,7 @@ porting notes -->
 #include <mapnik/grid/grid_pixfmt.hpp>
 #include <mapnik/grid/grid_pixel.hpp>
 #include <mapnik/grid/grid.hpp>
+#include <mapnik/grid/grid_marker_helpers.hpp>
 
 #include <mapnik/debug.hpp>
 #include <mapnik/geom_util.hpp>
@@ -67,7 +61,6 @@ porting notes -->
 #include <mapnik/svg/svg_storage.hpp>
 #include <mapnik/svg/svg_path_adapter.hpp>
 #include <mapnik/svg/svg_path_attributes.hpp>
-#include <mapnik/markers_placement.hpp>
 #include <mapnik/markers_symbolizer.hpp>
 
 // agg
@@ -75,15 +68,6 @@ porting notes -->
 #include "agg_rendering_buffer.h"
 #include "agg_pixfmt_rgba.h"
 #include "agg_rasterizer_scanline_aa.h"
-#include "agg_scanline_u.h"
-#include "agg_path_storage.h"
-#include "agg_conv_clip_polyline.h"
-#include "agg_conv_transform.h"
-#include "agg_image_filters.h"
-#include "agg_trans_bilinear.h"
-#include "agg_span_allocator.h"
-#include "agg_image_accessors.h"
-#include "agg_span_image_filter_rgba.h"
 
 // boost
 #include <boost/optional.hpp>
@@ -99,8 +83,12 @@ void grid_renderer<T>::process(markers_symbolizer const& sym,
                                mapnik::feature_impl & feature,
                                proj_transform const& prj_trans)
 {
-    typedef agg::renderer_base<mapnik::pixfmt_gray32> renderer_base;
+    typedef grid_rendering_buffer buf_type;
+    typedef mapnik::pixfmt_gray32 pixfmt_type;
+    typedef agg::renderer_base<pixfmt_type> renderer_base;
     typedef agg::renderer_scanline_bin_solid<renderer_base> renderer_type;
+    typedef label_collision_detector4 detector_type;
+    typedef boost::mpl::vector<clip_line_tag,clip_poly_tag,transform_tag,smooth_tag> conv_types;
 
     std::string filename = path_processor_type::evaluate(*sym.get_filename(), feature);
 
@@ -109,129 +97,166 @@ void grid_renderer<T>::process(markers_symbolizer const& sym,
         boost::optional<marker_ptr> mark = mapnik::marker_cache::instance()->find(filename, true);
         if (mark && *mark)
         {
-            if (!(*mark)->is_vector())
-            {
-                MAPNIK_LOG_DEBUG(agg_renderer) << "agg_renderer: markers_symbolizer does not yet support non-SVG markers";
-                return;
-            }
-
             ras_ptr->reset();
-            agg::scanline_bin sl;
-            grid_rendering_buffer buf(pixmap_.raw_data(), width_, height_, width_);
-            mapnik::pixfmt_gray32 pixf(buf);
-            renderer_base renb(pixf);
-            renderer_type ren(renb);
-
             agg::trans_affine geom_tr;
             evaluate_transform(geom_tr, feature, sym.get_transform());
+            agg::trans_affine tr = agg::trans_affine_scaling(scale_factor_*(1.0/pixmap_.get_resolution()));
 
-            boost::optional<svg_path_ptr> marker = (*mark)->get_vector_data();
-            box2d<double> const& bbox = (*marker)->bounding_box();
-
-            agg::trans_affine tr;
-            setup_transform_scaling(tr, bbox, feature, sym);
-            evaluate_transform(tr, feature, sym.get_image_transform());
-            // - clamp sizes to > 4 pixels of interactivity
-            if (tr.scale() < 0.5)
+            if ((*mark)->is_vector())
             {
-                agg::trans_affine tr2;
-                tr2 *= agg::trans_affine_scaling(0.5);
-                tr = tr2;
-            }
-            tr *= agg::trans_affine_scaling(scale_factor_*(1.0/pixmap_.get_resolution()));
+                using namespace mapnik::svg;
+                typedef agg::pod_bvector<path_attributes> svg_attribute_type;
+                typedef svg_renderer<svg_path_adapter,
+                                     svg_attribute_type,
+                                     renderer_type,
+                                     pixfmt_type > svg_renderer_type;
+                typedef vector_markers_rasterizer_dispatch_grid<buf_type,
+                                     svg_renderer_type,
+                                     grid_rasterizer,
+                                     detector_type,
+                                     mapnik::grid > dispatch_type;
+                boost::optional<svg_path_ptr> const& stock_vector_marker = (*mark)->get_vector_data();
+                expression_ptr const& width_expr = sym.get_width();
+                expression_ptr const& height_expr = sym.get_height();
 
-            coord2d center = bbox.center();
-            agg::trans_affine_translation recenter(-center.x, -center.y);
-            agg::trans_affine marker_trans = recenter * tr;
-
-            using namespace mapnik::svg;
-            vertex_stl_adapter<svg_path_storage> stl_storage((*marker)->source());
-            svg_path_adapter svg_path(stl_storage);
-
-            agg::pod_bvector<path_attributes> attributes;
-            bool result = push_explicit_style( (*marker)->attributes(), attributes, sym);
-
-            svg_renderer<svg_path_adapter,
-                         agg::pod_bvector<path_attributes>,
-                         renderer_type,
-                         mapnik::pixfmt_gray32 > svg_renderer(svg_path, result ? attributes : (*marker)->attributes());
-
-            marker_placement_e placement_method = sym.get_marker_placement();
-
-            bool placed = false;
-            BOOST_FOREACH( geometry_type & geom, feature.paths())
-            {
-                // TODO - merge this code with point_symbolizer rendering
-                if (placement_method == MARKER_POINT_PLACEMENT || geom.size() <= 1)
+                // special case for simple ellipse markers
+                // to allow for full control over rx/ry dimensions
+                if (filename == "shape://ellipse"
+                   && (width_expr || height_expr))
                 {
-                    double x;
-                    double y;
-                    double z=0;
-                    label::interior_position(geom, x, y);
-                    prj_trans.backward(x,y,z);
-                    t_.forward(&x,&y);
-                    geom_tr.transform(&x,&y);
-                    agg::trans_affine matrix = marker_trans;
-                    matrix.translate(x,y);
-                    box2d<double> transformed_bbox = bbox * matrix;
-
-                    if (sym.get_allow_overlap() ||
-                        detector_->has_placement(transformed_bbox))
+                    svg_storage_type marker_ellipse;
+                    vertex_stl_adapter<svg_path_storage> stl_storage(marker_ellipse.source());
+                    svg_path_adapter svg_path(stl_storage);
+                    // TODO - clamping to >= 4 pixels
+                    build_ellipse(sym, feature, marker_ellipse, svg_path);
+                    svg_attribute_type attributes;
+                    bool result = push_explicit_style( (*stock_vector_marker)->attributes(), attributes, sym);
+                    svg_renderer_type svg_renderer(svg_path, result ? attributes : (*stock_vector_marker)->attributes());
+                    evaluate_transform(tr, feature, sym.get_image_transform());
+                    box2d<double> bbox = marker_ellipse.bounding_box();
+                    coord2d center = bbox.center();
+                    agg::trans_affine_translation recenter(-center.x, -center.y);
+                    agg::trans_affine marker_trans = recenter * tr;
+                    buf_type render_buf(pixmap_.raw_data(), width_, height_, width_);
+                    dispatch_type rasterizer_dispatch(render_buf,
+                                                      svg_renderer,
+                                                      *ras_ptr,
+                                                      bbox,
+                                                      marker_trans,
+                                                      sym,
+                                                      *detector_,
+                                                      scale_factor_,
+                                                      feature,
+                                                      pixmap_);
+                    vertex_converter<box2d<double>, dispatch_type, markers_symbolizer,
+                                     CoordTransform, proj_transform, agg::trans_affine, conv_types>
+                        converter(query_extent_, rasterizer_dispatch, sym,t_,prj_trans,tr,scale_factor_);
+                    if (sym.clip() && feature.paths().size() > 0) // optional clip (default: true)
                     {
-                        placed = true;
-                        svg_renderer.render_id(*ras_ptr, sl, renb, feature.id(), matrix, 1, bbox);
-                        if (!sym.get_ignore_placement())
-                            detector_->insert(transformed_bbox);
+                        eGeomType type = feature.paths()[0].type();
+                        if (type == Polygon)
+                            converter.template set<clip_poly_tag>();
+                        else if (type == LineString)
+                            converter.template set<clip_line_tag>();
+                        // don't clip if type==Point
                     }
-                }
-                else if (sym.clip())
-                {
-                    typedef agg::conv_clip_polyline<geometry_type> clipped_geometry_type;
-                    typedef coord_transform<CoordTransform,clipped_geometry_type> path_type;
-                    typedef agg::conv_transform<path_type, agg::trans_affine> transformed_path_type;
-
-                    clipped_geometry_type clipped(geom);
-                    clipped.clip_box(query_extent_.minx(),query_extent_.miny(),query_extent_.maxx(),query_extent_.maxy());
-                    path_type path(t_,clipped,prj_trans);
-                    transformed_path_type path_transformed(path,geom_tr);
-                    markers_placement<transformed_path_type, label_collision_detector4> placement(path_transformed, bbox, marker_trans, *detector_,
-                                                                                                  sym.get_spacing() * scale_factor_,
-                                                                                                  sym.get_max_error(),
-                                                                                                  sym.get_allow_overlap());
-                    double x, y, angle;
-                    while (placement.get_point(x, y, angle))
+                    converter.template set<transform_tag>(); //always transform
+                    if (sym.smooth() > 0.0) converter.template set<smooth_tag>(); // optional smooth converter
+                    BOOST_FOREACH(geometry_type & geom, feature.paths())
                     {
-                        placed = true;
-                        agg::trans_affine matrix = marker_trans;
-                        matrix.rotate(angle);
-                        matrix.translate(x, y);
-                        svg_renderer.render_id(*ras_ptr, sl, renb, feature.id(), matrix, 1, bbox);
+                        converter.apply(geom);
                     }
                 }
                 else
                 {
-                    typedef coord_transform<CoordTransform,geometry_type> path_type;
-                    typedef agg::conv_transform<path_type, agg::trans_affine> transformed_path_type;
-                    path_type path(t_,geom,prj_trans);
-                    transformed_path_type path_transformed(path,geom_tr);
-                    markers_placement<transformed_path_type, label_collision_detector4> placement(path_transformed, bbox, marker_trans, *detector_,
-                                                                                                  sym.get_spacing() * scale_factor_,
-                                                                                                  sym.get_max_error(),
-                                                                                                  sym.get_allow_overlap());
-                    double x, y, angle;
-                    while (placement.get_point(x, y, angle))
+                    box2d<double> const& bbox = (*mark)->bounding_box();
+                    setup_transform_scaling(tr, bbox, feature, sym);
+                    evaluate_transform(tr, feature, sym.get_image_transform());
+                    // TODO - clamping to >= 4 pixels
+                    coord2d center = bbox.center();
+                    agg::trans_affine_translation recenter(-center.x, -center.y);
+                    agg::trans_affine marker_trans = recenter * tr;
+                    vertex_stl_adapter<svg_path_storage> stl_storage((*stock_vector_marker)->source());
+                    svg_path_adapter svg_path(stl_storage);
+                    svg_attribute_type attributes;
+                    bool result = push_explicit_style( (*stock_vector_marker)->attributes(), attributes, sym);
+                    svg_renderer_type svg_renderer(svg_path, result ? attributes : (*stock_vector_marker)->attributes());
+                    buf_type render_buf(pixmap_.raw_data(), width_, height_, width_);
+                    dispatch_type rasterizer_dispatch(render_buf,
+                                                      svg_renderer,
+                                                      *ras_ptr,
+                                                      bbox,
+                                                      marker_trans,
+                                                      sym,
+                                                      *detector_,
+                                                      scale_factor_,
+                                                      feature,
+                                                      pixmap_);
+                    vertex_converter<box2d<double>, dispatch_type, markers_symbolizer,
+                                     CoordTransform, proj_transform, agg::trans_affine, conv_types>
+                        converter(query_extent_, rasterizer_dispatch, sym,t_,prj_trans,tr,scale_factor_);
+                    if (sym.clip() && feature.paths().size() > 0) // optional clip (default: true)
                     {
-                        placed = true;
-                        agg::trans_affine matrix = marker_trans;
-                        matrix.rotate(angle);
-                        matrix.translate(x, y);
-                        svg_renderer.render_id(*ras_ptr, sl, renb, feature.id(), matrix, 1, bbox);
+                        eGeomType type = feature.paths()[0].type();
+                        if (type == Polygon)
+                            converter.template set<clip_poly_tag>();
+                        else if (type == LineString)
+                            converter.template set<clip_line_tag>();
+                        // don't clip if type==Point
+                    }
+                    converter.template set<transform_tag>(); //always transform
+                    if (sym.smooth() > 0.0) converter.template set<smooth_tag>(); // optional smooth converter
+                    BOOST_FOREACH(geometry_type & geom, feature.paths())
+                    {
+                        converter.apply(geom);
                     }
                 }
             }
-            if (placed)
+            else // raster markers
             {
-                pixmap_.add_feature(feature);
+                box2d<double> const& bbox = (*mark)->bounding_box();
+                setup_transform_scaling(tr, bbox, feature, sym);
+                evaluate_transform(tr, feature, sym.get_image_transform());
+                // - clamp sizes to > 4 pixels of interactivity
+                coord2d center = bbox.center();
+                agg::trans_affine_translation recenter(-center.x, -center.y);
+                agg::trans_affine marker_trans = recenter * tr;
+                boost::optional<mapnik::image_ptr> marker = (*mark)->get_bitmap_data();
+                typedef raster_markers_rasterizer_dispatch_grid<buf_type,
+                                                            grid_rasterizer,
+                                                            pixfmt_type,
+                                                            renderer_base,
+                                                            renderer_type,
+                                                            detector_type,
+                                                            mapnik::grid > dispatch_type;
+                buf_type render_buf(pixmap_.raw_data(), width_, height_, width_);
+                dispatch_type rasterizer_dispatch(render_buf,
+                                                  *ras_ptr,
+                                                  **marker,
+                                                  marker_trans,
+                                                  sym,
+                                                  *detector_,
+                                                  scale_factor_,
+                                                  feature,
+                                                  pixmap_);
+                vertex_converter<box2d<double>, dispatch_type, markers_symbolizer,
+                                 CoordTransform, proj_transform, agg::trans_affine, conv_types>
+                    converter(query_extent_, rasterizer_dispatch, sym,t_,prj_trans,tr,scale_factor_);
+                if (sym.clip() && feature.paths().size() > 0) // optional clip (default: true)
+                {
+                    eGeomType type = feature.paths()[0].type();
+                    if (type == Polygon)
+                        converter.template set<clip_poly_tag>();
+                    else if (type == LineString)
+                        converter.template set<clip_line_tag>();
+                    // don't clip if type==Point
+                }
+                converter.template set<transform_tag>(); //always transform
+                if (sym.smooth() > 0.0) converter.template set<smooth_tag>(); // optional smooth converter
+                BOOST_FOREACH(geometry_type & geom, feature.paths())
+                {
+                    converter.apply(geom);
+                }
             }
         }
     }