Polygon pattern on line geometries for Cairo backend

include/mapnik/cairo/render_polygon_pattern.hpp

@@ -0,0 +1,174 @@
+/*****************************************************************************
+ *
+ * This file is part of Mapnik (c++ mapping toolkit)
+ *
+ * Copyright (C) 2017 Artem Pavlenko
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ *****************************************************************************/
+
+#ifndef MAPNIK_CAIRO_RENDER_POLYGON_PATTERN_HPP
+#define MAPNIK_CAIRO_RENDER_POLYGON_PATTERN_HPP
+
+#include <mapnik/symbolizer.hpp>
+#include <mapnik/vertex_processor.hpp>
+#include <mapnik/vertex_converters.hpp>
+#include <mapnik/renderer_common/pattern_alignment.hpp>
+#include <mapnik/renderer_common/render_pattern.hpp>
+#include <mapnik/renderer_common/apply_vertex_converter.hpp>
+#include <mapnik/renderer_common/clipping_extent.hpp>
+#include <mapnik/agg_rasterizer.hpp>
+#include <mapnik/marker.hpp>
+
+namespace mapnik {
+
+struct cairo_renderer_process_visitor_p
+{
+    cairo_renderer_process_visitor_p(cairo_context & context,
+                                     agg::trans_affine & image_tr,
+                                     unsigned offset_x,
+                                     unsigned offset_y,
+                                     float opacity)
+        : context_(context),
+          image_tr_(image_tr),
+          offset_x_(offset_x),
+          offset_y_(offset_y),
+          opacity_(opacity) {}
+
+    void operator() (marker_null const&) {}
+
+    void operator() (marker_svg const& marker)
+    {
+        mapnik::rasterizer ras;
+        mapnik::box2d<double> const& bbox_image = marker.get_data()->bounding_box() * image_tr_;
+        mapnik::image_rgba8 image(bbox_image.width(), bbox_image.height());
+        render_pattern<image_rgba8>(ras, marker, image_tr_, 1.0, image);
+        cairo_pattern pattern(image, opacity_);
+        pattern.set_extend(CAIRO_EXTEND_REPEAT);
+        pattern.set_origin(offset_x_, offset_y_);
+        context_.set_pattern(pattern);
+    }
+
+    void operator() (marker_rgba8 const& marker)
+    {
+        cairo_pattern pattern(marker.get_data(), opacity_);
+        pattern.set_extend(CAIRO_EXTEND_REPEAT);
+        pattern.set_origin(offset_x_, offset_y_);
+        context_.set_pattern(pattern);
+    }
+
+  private:
+    cairo_context & context_;
+    agg::trans_affine & image_tr_;
+    unsigned offset_x_;
+    unsigned offset_y_;
+    float opacity_;
+};
+
+struct cairo_pattern_base
+{
+    mapnik::marker const& marker_;
+    renderer_common const& common_;
+    symbolizer_base const& sym_;
+    mapnik::feature_impl const& feature_;
+    proj_transform const& prj_trans_;
+
+    agg::trans_affine geom_transform() const
+    {
+        agg::trans_affine tr;
+        auto transform = get_optional<transform_type>(sym_, keys::geometry_transform);
+        if (transform)
+        {
+            evaluate_transform(tr, feature_, common_.vars_, *transform, common_.scale_factor_);
+        }
+        return tr;
+    }
+};
+
+template <typename VertexConverter>
+struct cairo_polygon_pattern : cairo_pattern_base
+{
+    cairo_polygon_pattern(mapnik::marker const& marker,
+                          renderer_common const& common,
+                          symbolizer_base const& sym,
+                          mapnik::feature_impl const& feature,
+                          proj_transform const& prj_trans)
+        : cairo_pattern_base{marker, common, sym, feature, prj_trans},
+          clip_(get<value_bool, keys::clip>(sym_, feature_, common_.vars_)),
+          clip_box_(clipping_extent(common)),
+          tr_(geom_transform()),
+          converter_(clip_box_, sym, common.t_, prj_trans, tr_,
+                     feature, common.vars_, common.scale_factor_)
+    {
+        value_double simplify_tolerance = get<value_double, keys::simplify_tolerance>(sym, feature, common_.vars_);
+        value_double smooth = get<value_double, keys::smooth>(sym, feature, common_.vars_);
+
+        converter_.template set<affine_transform_tag>();
+        if (simplify_tolerance > 0.0) converter_.template set<simplify_tag>();
+        if (smooth > 0.0) converter_.template set<smooth_tag>();
+    }
+
+    void render(cairo_fill_rule_t fill_rule, cairo_context & context)
+    {
+        unsigned offset_x=0;
+        unsigned offset_y=0;
+        pattern_alignment_enum alignment = get<pattern_alignment_enum, keys::alignment>(sym_, feature_, common_.vars_);
+        if (alignment == LOCAL_ALIGNMENT)
+        {
+            double x0 = 0.0;
+            double y0 = 0.0;
+            using apply_local_alignment = detail::apply_local_alignment;
+            apply_local_alignment apply(common_.t_, prj_trans_, clip_box_, x0, y0);
+            util::apply_visitor(geometry::vertex_processor<apply_local_alignment>(apply), feature_.get_geometry());
+            offset_x = std::abs(clip_box_.width() - x0);
+            offset_y = std::abs(clip_box_.height() - y0);
+        }
+
+        value_double opacity = get<value_double, keys::opacity>(sym_, feature_, common_.vars_);
+        agg::trans_affine image_tr = agg::trans_affine_scaling(common_.scale_factor_);
+        auto image_transform = get_optional<transform_type>(sym_, keys::image_transform);
+        if (image_transform)
+        {
+            evaluate_transform(image_tr, feature_, common_.vars_, *image_transform, common_.scale_factor_);
+        }
+
+        composite_mode_e comp_op = get<composite_mode_e, keys::comp_op>(sym_, feature_, common_.vars_);
+
+        cairo_save_restore guard(context);
+        context.set_operator(comp_op);
+
+        util::apply_visitor(cairo_renderer_process_visitor_p(
+            context, image_tr, offset_x, offset_y, opacity), marker_);
+
+        using apply_vertex_converter_type = detail::apply_vertex_converter<VertexConverter, cairo_context>;
+        using vertex_processor_type = geometry::vertex_processor<apply_vertex_converter_type>;
+        apply_vertex_converter_type apply(converter_, context);
+        mapnik::util::apply_visitor(vertex_processor_type(apply),feature_.get_geometry());
+        // fill polygon
+        context.set_fill_rule(fill_rule);
+        context.fill();
+    }
+
+    const bool clip_;
+    const box2d<double> clip_box_;
+    const agg::trans_affine tr_;
+    VertexConverter converter_;
+};
+
+} // namespace mapnik
+
+
+#endif // MAPNIK_CAIRO_RENDER_POLYGON_PATTERN_HPP

src/cairo/process_line_pattern_symbolizer.cpp

@@ -27,6 +27,7 @@
 #include <mapnik/feature.hpp>
 #include <mapnik/proj_transform.hpp>
 #include <mapnik/cairo/cairo_renderer.hpp>
+#include <mapnik/cairo/render_polygon_pattern.hpp>
 #include <mapnik/renderer_common/render_pattern.hpp>
 #include <mapnik/vertex_converters.hpp>
 #include <mapnik/vertex_processor.hpp>
@@ -38,13 +39,16 @@
 namespace mapnik
 {
 
-struct cairo_renderer_process_visitor_l
+namespace
 {
-    cairo_renderer_process_visitor_l(renderer_common const& common,
+
-                                   line_pattern_symbolizer const& sym,
+struct prepare_pattern_visitor
-                                   mapnik::feature_impl & feature,
+{
-                                   std::size_t & width,
+    prepare_pattern_visitor(renderer_common const& common,
-                                   std::size_t & height)
+                            symbolizer_base const& sym,
+                            feature_impl const& feature,
+                            std::size_t & width,
+                            std::size_t & height)
         : common_(common),
           sym_(sym),
           feature_(feature),
@@ -79,86 +83,156 @@ struct cairo_renderer_process_visitor_l
 
   private:
     renderer_common const& common_;
-    line_pattern_symbolizer const& sym_;
+    symbolizer_base const& sym_;
-    mapnik::feature_impl & feature_;
+    feature_impl const& feature_;
     std::size_t & width_;
     std::size_t & height_;
 };
 
+template <typename... Converters>
+using vertex_converter_type = vertex_converter<clip_line_tag,
+                                               transform_tag,
+                                               affine_transform_tag,
+                                               simplify_tag,
+                                               smooth_tag,
+                                               offset_transform_tag,
+                                               Converters...>;
+
+struct warp_pattern : cairo_pattern_base
+{
+    using vc_type = vertex_converter_type<>;
+
+    warp_pattern(mapnik::marker const& marker,
+                 renderer_common const& common,
+                 symbolizer_base const& sym,
+                 mapnik::feature_impl const& feature,
+                 proj_transform const& prj_trans)
+        : cairo_pattern_base{marker, common, sym, feature, prj_trans},
+          clip_(get<value_bool, keys::clip>(sym, feature, common.vars_)),
+          offset_(get<value_double, keys::offset>(sym, feature, common.vars_)),
+          clip_box_(clipping_extent(common)),
+          tr_(geom_transform()),
+          converter_(clip_box_, sym, common.t_, prj_trans, tr_,
+                     feature, common.vars_, common.scale_factor_)
+    {
+        value_double offset = get<value_double, keys::offset>(sym, feature, common.vars_);
+        value_double simplify_tolerance = get<value_double, keys::simplify_tolerance>(sym, feature, common.vars_);
+        value_double smooth = get<value_double, keys::smooth>(sym, feature, common.vars_);
+
+        if (std::fabs(offset) > 0.0) converter_.template set<offset_transform_tag>();
+        converter_.template set<affine_transform_tag>();
+        if (simplify_tolerance > 0.0) converter_.template set<simplify_tag>();
+        if (smooth > 0.0) converter_.template set<smooth_tag>();
+        if (clip_) converter_.template set<clip_line_tag>();
+    }
+
+    box2d<double> clip_box() const
+    {
+        box2d<double> clipping_extent = common_.query_extent_;
+        if (clip_)
+        {
+            double pad_per_pixel = static_cast<double>(common_.query_extent_.width() / common_.width_);
+            double pixels = std::ceil(std::max(marker_.width() / 2.0 + std::fabs(offset_),
+                                              (std::fabs(offset_) * offset_converter_default_threshold)));
+            double padding = pad_per_pixel * pixels * common_.scale_factor_;
+
+            clipping_extent.pad(padding);
+        }
+        return clipping_extent;
+    }
+
+    void render(cairo_context & context)
+    {
+        std::size_t width = marker_.width();
+        std::size_t height = marker_.height();
+
+        // TODO - re-implement at renderer level like polygon_pattern symbolizer
+        prepare_pattern_visitor visit(common_, sym_, feature_, width, height);
+        std::shared_ptr<cairo_pattern> pattern = util::apply_visitor(visit, marker_);
+        pattern->set_extend(CAIRO_EXTEND_REPEAT);
+        pattern->set_filter(CAIRO_FILTER_BILINEAR);
+
+        composite_mode_e comp_op = get<composite_mode_e, keys::comp_op>(sym_, feature_, common_.vars_);
+
+        cairo_save_restore guard(context);
+        context.set_operator(comp_op);
+        context.set_line_width(height);
+
+        using rasterizer_type = line_pattern_rasterizer<cairo_context>;
+        rasterizer_type ras(context, *pattern, width, height);
+
+        using apply_vertex_converter_type = detail::apply_vertex_converter<
+            vc_type, rasterizer_type>;
+        using vertex_processor_type = geometry::vertex_processor<apply_vertex_converter_type>;
+        apply_vertex_converter_type apply(converter_, ras);
+        mapnik::util::apply_visitor(vertex_processor_type(apply), feature_.get_geometry());
+    }
+
+    const bool clip_;
+    const double offset_;
+    const box2d<double> clip_box_;
+    const agg::trans_affine tr_;
+    vc_type converter_;
+};
+
+using repeat_pattern_base = cairo_polygon_pattern<vertex_converter_type<dash_tag,
+                                                                        stroke_tag>>;
+
+struct repeat_pattern : repeat_pattern_base
+{
+    using repeat_pattern_base::cairo_polygon_pattern;
+
+    void render(cairo_context & context)
+    {
+        if (has_key(sym_, keys::stroke_dasharray))
+        {
+            converter_.template set<dash_tag>();
+        }
+
+        if (clip_) converter_.template set<clip_line_tag>();
+
+        value_double offset = get<value_double, keys::offset>(sym_, feature_, common_.vars_);
+        if (std::fabs(offset) > 0.0) converter_.template set<offset_transform_tag>();
+
+        repeat_pattern_base::render(CAIRO_FILL_RULE_WINDING, context);
+    }
+};
+
+}
+
 template <typename T>
 void cairo_renderer<T>::process(line_pattern_symbolizer const& sym,
-                                  mapnik::feature_impl & feature,
+                                feature_impl & feature,
-                                  proj_transform const& prj_trans)
+                                proj_transform const& prj_trans)
 {
     std::string filename = get<std::string, keys::file>(sym, feature, common_.vars_);
-    composite_mode_e comp_op = get<composite_mode_e, keys::comp_op>(sym, feature, common_.vars_);
+    std::shared_ptr<mapnik::marker const> marker = marker_cache::instance().find(filename, true);
-    value_bool clip = get<value_bool, keys::clip>(sym, feature, common_.vars_);
-    value_double offset = get<value_double, keys::offset>(sym, feature, common_.vars_);
-    value_double simplify_tolerance = get<value_double, keys::simplify_tolerance>(sym, feature, common_.vars_);
-    value_double smooth = get<value_double, keys::smooth>(sym, feature, common_.vars_);
 
-    if (filename.empty())
+    if (marker->is<mapnik::marker_null>())
     {
         return;
     }
 
-    std::shared_ptr<mapnik::marker const> marker = marker_cache::instance().find(filename, true);
+    line_pattern_enum pattern = get<line_pattern_enum, keys::line_pattern>(sym, feature, common_.vars_);
-
+    switch (pattern)
-    if (marker->is<mapnik::marker_null>()) return;
-
-    std::size_t width = marker->width();
-    std::size_t height = marker->height();
-
-    cairo_save_restore guard(context_);
-    context_.set_operator(comp_op);
-    // TODO - re-implement at renderer level like polygon_pattern symbolizer
-    cairo_renderer_process_visitor_l visit(common_,
-                                           sym,
-                                           feature,
-                                           width,
-                                           height);
-    std::shared_ptr<cairo_pattern> pattern = util::apply_visitor(visit, *marker);
-
-    context_.set_line_width(height);
-
-    pattern->set_extend(CAIRO_EXTEND_REPEAT);
-    pattern->set_filter(CAIRO_FILTER_BILINEAR);
-
-    agg::trans_affine tr;
-    auto geom_transform = get_optional<transform_type>(sym, keys::geometry_transform);
-    if (geom_transform) { evaluate_transform(tr, feature, common_.vars_, *geom_transform, common_.scale_factor_); }
-
-    box2d<double> clipping_extent = common_.query_extent_;
-    if (clip)
     {
-        double pad_per_pixel = static_cast<double>(common_.query_extent_.width()/common_.width_);
+        case LINE_PATTERN_WARP:
-        double pixels = std::ceil(std::max(width / 2.0 + std::fabs(offset),
+        {
-                                          (std::fabs(offset) * offset_converter_default_threshold)));
+            warp_pattern pattern(*marker, common_, sym, feature, prj_trans);
-        double padding = pad_per_pixel * pixels * common_.scale_factor_;
+            pattern.render(context_);
-
+            break;
-        clipping_extent.pad(padding);
+        }
+        case LINE_PATTERN_REPEAT:
+        {
+            repeat_pattern pattern(*marker, common_, sym, feature, prj_trans);
+            pattern.render(context_);
+            break;
+        }
+        case line_pattern_enum_MAX:
+        default:
+            MAPNIK_LOG_ERROR(process_line_pattern_symbolizer) << "Incorrect line-pattern value.";
     }
 
-    using rasterizer_type = line_pattern_rasterizer<cairo_context>;
-    rasterizer_type ras(context_, *pattern, width, height);
-    using vertex_converter_type = vertex_converter<clip_line_tag, transform_tag,
-                                                   affine_transform_tag,
-                                                   simplify_tag, smooth_tag,
-                                                   offset_transform_tag>;
-
-    vertex_converter_type converter(clipping_extent,sym, common_.t_, prj_trans, tr, feature, common_.vars_, common_.scale_factor_);
-
-    if (clip) converter.set<clip_line_tag>();
-    converter.set<transform_tag>(); // always transform
-    if (std::fabs(offset) > 0.0) converter.set<offset_transform_tag>(); // parallel offset
-    converter.set<affine_transform_tag>(); // optional affine transform
-    if (simplify_tolerance > 0.0) converter.set<simplify_tag>(); // optional simplify converter
-    if (smooth > 0.0) converter.set<smooth_tag>(); // optional smooth converter
-
-    using apply_vertex_converter_type = detail::apply_vertex_converter<vertex_converter_type, rasterizer_type>;
-    using vertex_processor_type = geometry::vertex_processor<apply_vertex_converter_type>;
-    apply_vertex_converter_type apply(converter, ras);
-    mapnik::util::apply_visitor(vertex_processor_type(apply), feature.get_geometry());
 }
 
 template void cairo_renderer<cairo_ptr>::process(line_pattern_symbolizer const&,

src/cairo/process_polygon_pattern_symbolizer.cpp

@@ -27,123 +27,38 @@
 #include <mapnik/proj_transform.hpp>
 #include <mapnik/cairo/cairo_renderer.hpp>
 #include <mapnik/cairo/cairo_render_vector.hpp>
-#include <mapnik/renderer_common/render_pattern.hpp>
+#include <mapnik/cairo/render_polygon_pattern.hpp>
 #include <mapnik/vertex_converters.hpp>
 #include <mapnik/vertex_processor.hpp>
 #include <mapnik/marker.hpp>
 #include <mapnik/marker_cache.hpp>
-#include <mapnik/agg_rasterizer.hpp>
-#include <mapnik/renderer_common/clipping_extent.hpp>
 #include <mapnik/renderer_common/apply_vertex_converter.hpp>
 #include <mapnik/renderer_common/pattern_alignment.hpp>
 
 namespace mapnik
 {
 
-struct cairo_renderer_process_visitor_p
-{
-    cairo_renderer_process_visitor_p(cairo_context & context,
-                                   agg::trans_affine & image_tr,
-                                   unsigned offset_x,
-                                   unsigned offset_y,
-                                   float opacity)
-        : context_(context),
-          image_tr_(image_tr),
-          offset_x_(offset_x),
-          offset_y_(offset_y),
-          opacity_(opacity) {}
-
-    void operator() (marker_null const&) {}
-
-    void operator() (marker_svg const& marker)
-    {
-        mapnik::rasterizer ras;
-        mapnik::box2d<double> const& bbox_image = marker.get_data()->bounding_box() * image_tr_;
-        mapnik::image_rgba8 image(bbox_image.width(), bbox_image.height());
-        render_pattern<image_rgba8>(ras, marker, image_tr_, 1.0, image);
-        cairo_pattern pattern(image, opacity_);
-        pattern.set_extend(CAIRO_EXTEND_REPEAT);
-        pattern.set_origin(offset_x_, offset_y_);
-        context_.set_pattern(pattern);
-    }
-
-    void operator() (marker_rgba8 const& marker)
-    {
-        cairo_pattern pattern(marker.get_data(), opacity_);
-        pattern.set_extend(CAIRO_EXTEND_REPEAT);
-        pattern.set_origin(offset_x_, offset_y_);
-        context_.set_pattern(pattern);
-    }
-
-  private:
-    cairo_context & context_;
-    agg::trans_affine & image_tr_;
-    unsigned offset_x_;
-    unsigned offset_y_;
-    float opacity_;
-};
-
 template <typename T>
 void cairo_renderer<T>::process(polygon_pattern_symbolizer const& sym,
                                   mapnik::feature_impl & feature,
                                   proj_transform const& prj_trans)
 {
-    composite_mode_e comp_op = get<composite_mode_e, keys::comp_op>(sym, feature, common_.vars_);
     std::string filename = get<std::string, keys::file>(sym, feature, common_.vars_);
-    value_bool clip = get<value_bool, keys::clip>(sym, feature, common_.vars_);
-    value_double simplify_tolerance = get<value_double, keys::simplify_tolerance>(sym, feature, common_.vars_);
-    value_double smooth = get<value_double, keys::smooth>(sym, feature, common_.vars_);
-    value_double opacity = get<value_double, keys::opacity>(sym, feature, common_.vars_);
-    agg::trans_affine image_tr = agg::trans_affine_scaling(common_.scale_factor_);
-    auto image_transform = get_optional<transform_type>(sym, keys::image_transform);
-    if (image_transform) evaluate_transform(image_tr, feature, common_.vars_, *image_transform, common_.scale_factor_);
-
-    cairo_save_restore guard(context_);
-    context_.set_operator(comp_op);
-
     std::shared_ptr<mapnik::marker const> marker = mapnik::marker_cache::instance().find(filename,true);
     if (marker->is<mapnik::marker_null>()) return;
 
-    unsigned offset_x=0;
-    unsigned offset_y=0;
-    box2d<double> const& clip_box = clipping_extent(common_);
-    pattern_alignment_enum alignment = get<pattern_alignment_enum, keys::alignment>(sym, feature, common_.vars_);
-    if (alignment == LOCAL_ALIGNMENT)
-    {
-        double x0 = 0.0;
-        double y0 = 0.0;
-        using apply_local_alignment = detail::apply_local_alignment;
-        apply_local_alignment apply(common_.t_, prj_trans, clip_box, x0, y0);
-        util::apply_visitor(geometry::vertex_processor<apply_local_alignment>(apply), feature.get_geometry());
-        offset_x = std::abs(clip_box.width() - x0);
-        offset_y = std::abs(clip_box.height() - y0);
-    }
-
-    util::apply_visitor(cairo_renderer_process_visitor_p(context_, image_tr, offset_x, offset_y, opacity), *marker);
-
-    agg::trans_affine tr;
-    auto geom_transform = get_optional<transform_type>(sym, keys::geometry_transform);
-    if (geom_transform) { evaluate_transform(tr, feature, common_.vars_, *geom_transform, common_.scale_factor_); }
     using vertex_converter_type = vertex_converter<clip_poly_tag,
                                                    transform_tag,
                                                    affine_transform_tag,
                                                    simplify_tag,
                                                    smooth_tag>;
+    using pattern_type = cairo_polygon_pattern<vertex_converter_type>;
 
-    vertex_converter_type converter(clip_box,sym,common_.t_,prj_trans,tr,feature,common_.vars_,common_.scale_factor_);
+    pattern_type pattern(*marker, common_, sym, feature, prj_trans);
-    if (prj_trans.equal() && clip) converter.set<clip_poly_tag>();
-    converter.set<transform_tag>(); //always transform
-    converter.set<affine_transform_tag>();
-    if (simplify_tolerance > 0.0) converter.set<simplify_tag>(); // optional simplify converter
-    if (smooth > 0.0) converter.set<smooth_tag>(); // optional smooth converter
 
-    using apply_vertex_converter_type = detail::apply_vertex_converter<vertex_converter_type, cairo_context>;
+    if (prj_trans.equal() && pattern.clip_) pattern.converter_.set<clip_poly_tag>();
-    using vertex_processor_type = geometry::vertex_processor<apply_vertex_converter_type>;
+
-    apply_vertex_converter_type apply(converter, context_);
+    pattern.render(CAIRO_FILL_RULE_EVEN_ODD, context_);
-    mapnik::util::apply_visitor(vertex_processor_type(apply),feature.get_geometry());
-    // fill polygon
-    context_.set_fill_rule(CAIRO_FILL_RULE_EVEN_ODD);
-    context_.fill();
 }
 
 template void cairo_renderer<cairo_ptr>::process(polygon_pattern_symbolizer const&,