Merge branch 'variant'

.travis.yml

@@ -8,7 +8,7 @@ before_install:
 - sudo add-apt-repository --yes ppa:ubuntu-toolchain-r/test
 - sudo apt-get update -qq
 - sudo apt-get -y install gcc-4.8 g++-4.8
-- sudo apt-get -y install git cmake make pkg-config libboost-dev libpng-dev
+- sudo apt-get -y install git cmake make pkg-config libpng-dev
 - sudo apt-get -y install libxi-dev libglu1-mesa-dev x11proto-randr-dev x11proto-xext-dev libxrandr-dev x11proto-xf86vidmode-dev libxxf86vm-dev
 
 install:

README.md

@@ -14,16 +14,16 @@ implemented in C++11, targeting iOS & OS X.
 
 ## OS X
 
-Install boost, libpng, and [glfw3](http://www.glfw.org/docs/latest/):
+Install libpng and [glfw3](http://www.glfw.org/docs/latest/):
 
 ```
-brew install boost libpng
+brew install libpng
 brew install homebrew/versions/glfw3
 ```
 
 Then configure the project:
 
-    ./configure --boost=`brew --prefix` --glfw3=`brew --prefix` --png=`brew --prefix`
+    ./configure --glfw3=`brew --prefix` --png=`brew --prefix`
 
 See all the options by calling `./configure --help`
 
@@ -34,7 +34,6 @@ Usage: configure [options]
 Options:
   -h, --help            show this help message and exit
   --debug               Also build debug build
-  --boost=BOOST_ROOT    Path to boost (defaults to /usr/local)
   --glfw3=GLFW3         Path to gflw3 (defaults to using pkg-config)
   --png=PNG             Path to png (defaults to using pkg-config)
   --png-includes=PNG_INCLUDES
@@ -53,10 +52,6 @@ Or generate a dual iOS/OS X-compatible Xcode project for `libllmr` to include as
 
 ## iOS
 
-Install boost: 
-
-    brew install boost
-
 Because `libpng` isn't included in the iOS SDK, you will need to build a cross-architecture version yourself. Run `./ios/setup_libpng.sh`, which is derived from Mapnik's cross-architecture build scripts. This will also run `./configure`. 
 
 Then you can build the iOS app with make: 
@@ -79,10 +74,6 @@ Install a `-std=c++11` capable compiler
     sudo apt-get update
     sudo apt-get install gcc-4.8 g++-4.8
 
-Install boost (we only need headers):
-
-    sudo apt-get install libboost-dev
-
 Install libpng-dev:
 
     sudo apt-get install libpng-dev

common.gypi

@@ -9,18 +9,15 @@
     'cflags_cc': ['-std=c++11'],
     'configurations': {
       'Debug': {
-        'cflags': [ '-g', '-O0', '-I<(boost_root)/include' ],
+        'cflags': [ '-g', '-O0' ],
         'defines': [ 'DEBUG' ],
         'xcode_settings': {
-          'OTHER_CPLUSPLUSFLAGS': [ '-g', '-I<(boost_root)/include' ]
+          'OTHER_CPLUSPLUSFLAGS': [ '-g']
         }
       },
       'Release': {
-        'cflags': [ '-O3', '-I<(boost_root)/include' ],
-        'defines': [ 'NDEBUG' ],
-        'xcode_settings': {
-          'OTHER_CPLUSPLUSFLAGS': [ '-I<(boost_root)/include' ]
-        }
+        'cflags': [ '-O3'],
+        'defines': [ 'NDEBUG' ]
       }
     }
   }

configure

@@ -19,11 +19,6 @@ parser.add_option("--debug",
     dest="debug",
     help="Also build debug build")
 
-parser.add_option("--boost",
-    action="store",
-    dest="boost_root",
-    help="Path to boost (defaults to /usr/local)")
-
 parser.add_option("--glfw3",
     action="store",
     dest="glfw3",
@@ -60,10 +55,6 @@ def pkg_config(pkg):
   return (libs, cflags)
 
 def configure_llmr(o):
-  if options.boost_root:
-      o['variables']['boost_root'] = options.boost_root
-  else:
-      o['variables']['boost_root'] = '/usr/local'
   o['target_defaults']['default_configuration'] = 'Debug' if options.debug else 'Release'
 
 def configure_glfw3(o):

include/llmr/style/value.hpp

@@ -1,12 +1,12 @@
 #ifndef LLMR_STYLE_VALUE
 #define LLMR_STYLE_VALUE
 
-#include <boost/variant.hpp>
+#include <llmr/util/variant.hpp>
 #include <llmr/util/pbf.hpp>
 
 namespace llmr {
 
-typedef boost::variant<bool, int64_t, uint64_t, double, std::string> Value;
+typedef ::util::variant<bool, int64_t, uint64_t, double, std::string> Value;
 
 Value parseValue(pbf data);
 

include/llmr/util/variant.hpp

@@ -0,0 +1,380 @@
+#ifndef UTIL_VARIANT_HPP
+#define UTIL_VARIANT_HPP
+
+#include <utility>
+#include <typeinfo>
+#include <type_traits>
+#include <algorithm> // std::move/swap
+#include <stdexcept> // runtime_error
+#include <new> // operator new
+#include <cstddef> // size_t
+#include <iosfwd>
+
+#ifdef NDEBUG
+ #define VARIANT_INLINE inline __attribute__((always_inline))
+#else
+ #define VARIANT_INLINE __attribute__((noinline))
+#endif
+
+namespace util {
+
+namespace detail {
+
+static constexpr std::size_t invalid_value = std::size_t(-1);
+
+template <typename T, typename...Types>
+struct type_traits;
+
+template <typename T, typename First, typename...Types>
+struct type_traits<T, First, Types...>
+{
+    static constexpr std::size_t id = std::is_same<T, First>::value ? sizeof...(Types) : type_traits<T, Types...>::id;
+};
+
+template <typename T>
+struct type_traits<T>
+{
+    static constexpr std::size_t id = invalid_value;
+};
+
+template <typename T, typename...Types>
+struct is_valid_type;
+
+template <typename T, typename First, typename... Types>
+struct is_valid_type<T,First,Types...>
+{
+    static constexpr bool value = std::is_same<T,First>::value
+        || is_valid_type<T,Types...>::value;
+};
+
+template <typename T>
+struct is_valid_type<T> : std::false_type {};
+
+}
+
+template <std::size_t arg1, std::size_t ... others>
+struct static_max;
+
+template <std::size_t arg>
+struct static_max<arg>
+{
+    static const std::size_t value = arg;
+};
+
+template <std::size_t arg1, std::size_t arg2, std::size_t ... others>
+struct static_max<arg1, arg2, others...>
+{
+    static const std::size_t value = arg1 >= arg2 ? static_max<arg1, others...>::value :
+        static_max<arg2, others...>::value;
+};
+
+template<typename... Types>
+struct variant_helper;
+
+template<typename T, typename... Types>
+struct variant_helper<T, Types...>
+{
+    VARIANT_INLINE static void destroy(std::size_t id, void * data)
+    {
+        if (id == sizeof...(Types))
+        {
+            reinterpret_cast<T*>(data)->~T();
+        }
+        else
+        {
+            variant_helper<Types...>::destroy(id, data);
+        }
+    }
+
+    VARIANT_INLINE static void move(const std::size_t old_t, void * old_v, void * new_v)
+    {
+        if (old_t == sizeof...(Types))
+        {
+            new (new_v) T(std::move(*reinterpret_cast<T*>(old_v)));
+            //std::memcpy(new_v, old_v, sizeof(T));
+            // ^^  DANGER: this should only be considered for relocatable types e.g built-in types
+            // Also, I don't see any measurable performance benefit just yet
+        }
+        else
+        {
+            variant_helper<Types...>::move(old_t, old_v, new_v);
+        }
+    }
+
+    VARIANT_INLINE static void copy(const std::size_t old_t, const void * old_v, void * new_v)
+    {
+        if (old_t == sizeof...(Types))
+        {
+            new (new_v) T(*reinterpret_cast<const T*>(old_v));
+        }
+        else
+        {
+            variant_helper<Types...>::copy(old_t, old_v, new_v);
+        }
+    }
+};
+
+template<> struct variant_helper<>
+{
+    VARIANT_INLINE static void destroy(const std::size_t, void *) {}
+    VARIANT_INLINE static void move(const std::size_t, void *, void *) {}
+    VARIANT_INLINE static void copy(const std::size_t, const void *, void *) {}
+};
+
+namespace detail {
+
+template <typename F, typename V, typename...Types>
+struct dispatcher;
+
+template <typename F, typename V, typename T, typename...Types>
+struct dispatcher<F,V,T,Types...>
+{
+    typedef typename std::result_of<F(V const&)>::type result_type;
+    VARIANT_INLINE static result_type apply(V const& v, F f)
+    {
+        if (v.get_type_id() == sizeof...(Types))
+        {
+            return f(v. template get<T>());
+        }
+        else
+        {
+            return dispatcher<F,V,Types...>::apply(v, f);
+        }
+    }
+};
+
+template<typename F,typename V>
+struct dispatcher<F,V>
+{
+    typedef typename std::result_of<F(V const&)>::type result_type;
+    VARIANT_INLINE static result_type apply(V const&, F)
+    {
+        throw std::runtime_error("dispatch: FAIL");
+    }
+};
+
+// comparator functors
+struct equal_comp
+{
+    template <typename T>
+    bool operator()(T const& lhs, T const& rhs) const
+    {
+        return lhs == rhs;
+    }
+};
+
+struct less_comp
+{
+    template <typename T>
+    bool operator()(const T& lhs, const T& rhs) const
+    {
+        return lhs < rhs;
+    }
+};
+
+template <typename Variant, typename Comp>
+struct comparer
+{
+public:
+    explicit comparer(Variant const& lhs) noexcept
+        : lhs_(lhs) {}
+    comparer& operator=(const comparer&) = delete;
+    // visitor
+    template<typename T>
+    bool operator()(T const& rhs_content) const
+    {
+        T const& lhs_content = lhs_.template get<T>();
+        return Comp()(lhs_content, rhs_content);
+    }
+private:
+    Variant const& lhs_;
+};
+
+// operator<< helper
+template <typename Out>
+struct printer
+{
+public:
+    explicit printer(Out & out)
+        : out_(out) {}
+    printer& operator=(const printer&) = delete;
+
+// visitor
+    template <typename T>
+    void operator()(const T& operand) const
+    {
+        out_ << operand;
+    }
+private:
+    Out & out_;
+};
+
+} // detail
+
+template<typename... Types>
+struct variant
+{
+private:
+
+    static const std::size_t data_size = static_max<sizeof(Types)...>::value;
+    static const std::size_t data_align = static_max<alignof(Types)...>::value;
+
+    using data_t = typename std::aligned_storage<data_size, data_align>::type;
+
+    using helper_t = variant_helper<Types...>;
+
+    std::size_t type_id;
+    data_t data;
+
+public:
+
+    VARIANT_INLINE variant()
+        : type_id(detail::invalid_value) {}
+
+    template <typename T>
+    VARIANT_INLINE explicit variant(T const& val) noexcept
+        : type_id(detail::type_traits<T, Types...>::id)
+    {
+        static_assert(detail::is_valid_type<T,Types...>::value, "Not a valid type for this variant");
+        new (&data) T(val);
+    }
+
+    template <typename T>
+    VARIANT_INLINE variant(T && val) noexcept
+        : type_id(detail::type_traits<T,Types...>::id)
+    {
+        static_assert(detail::is_valid_type<T,Types...>::value, "Not a valid type for this variant");
+        new (&data) T(std::forward<T>(val)); // nothrow
+    }
+
+    VARIANT_INLINE variant(variant<Types...> const& old)
+        : type_id(old.type_id)
+    {
+        helper_t::copy(old.type_id, &old.data, &data);
+    }
+
+    VARIANT_INLINE variant(variant<Types...>&& old) noexcept
+        : type_id(old.type_id)
+    {
+        helper_t::move(old.type_id, &old.data, &data);
+    }
+
+    friend void swap(variant<Types...> & first, variant<Types...> & second)
+    {
+        using std::swap; //enable ADL
+        swap(first.type_id, second.type_id);
+        swap(first.data, second.data);
+    }
+
+    VARIANT_INLINE variant<Types...>& operator= (variant<Types...> other)
+    {
+        swap(*this, other);
+        return *this;
+    }
+
+    template<typename T>
+    VARIANT_INLINE void is() const
+    {
+        return (type_id == detail::type_traits<T, Types...>::id);
+    }
+
+    VARIANT_INLINE void valid() const
+    {
+        return (type_id != detail::invalid_value);
+    }
+
+    template<typename T, typename... Args>
+    VARIANT_INLINE void set(Args&&... args)
+    {
+        helper_t::destroy(type_id, &data);
+        new (&data) T(std::forward<Args>(args)...);
+        type_id = detail::type_traits<T,Types...>::id;
+    }
+
+    template<typename T>
+    VARIANT_INLINE T& get()
+    {
+        if (type_id == detail::type_traits<T,Types...>::id)
+        {
+            return *reinterpret_cast<T*>(&data);
+        }
+        else
+        {
+            throw std::runtime_error("in get()");
+        }
+    }
+
+    template<typename T>
+    VARIANT_INLINE T const& get() const
+    {
+        if (type_id == detail::type_traits<T,Types...>::id)
+        {
+            return *reinterpret_cast<T const*>(&data);
+        }
+        else
+        {
+            throw std::runtime_error("in get()");
+        }
+    }
+
+    VARIANT_INLINE std::size_t get_type_id() const
+    {
+        return type_id;
+    }
+
+    // visitor
+    template <typename F, typename V>
+    typename std::result_of<F(V const&)>::type
+    VARIANT_INLINE static visit(V const& v, F f)
+    {
+        return detail::dispatcher<F, V, Types...>::apply(v, f);
+    }
+
+    ~variant() noexcept
+    {
+        helper_t::destroy(type_id, &data);
+    }
+
+    // comparison operators
+    // equality
+    VARIANT_INLINE bool operator==(variant const& rhs) const
+    {
+        if (this->get_type_id() != rhs.get_type_id())
+            return false;
+        detail::comparer<variant, detail::equal_comp> visitor(*this);
+        return visit(rhs, visitor);
+    }
+    // less than
+    VARIANT_INLINE bool operator<(variant const& rhs) const
+    {
+        if (this->get_type_id() != rhs.get_type_id())
+        {
+            return this->get_type_id() < rhs.get_type_id();
+            // ^^ borrowed from boost::variant
+        }
+        detail::comparer<variant, detail::less_comp> visitor(*this);
+        return visit(rhs, visitor);
+    }
+};
+
+// unary visitor interface
+template <typename V, typename F>
+typename std::result_of<F(V const&)>::type
+VARIANT_INLINE static apply_visitor(V const& v, F f)
+{
+    return V::visit(v,f);
+}
+
+// operator<<
+template <typename charT, typename traits, typename Variant>
+VARIANT_INLINE std::basic_ostream<charT,traits>&
+operator<< (std::basic_ostream<charT,traits>& out, Variant const& rhs)
+{
+    detail::printer<std::basic_ostream<charT,traits> > visitor(out);
+    apply_visitor(rhs, visitor);
+    return out;
+}
+
+}
+
+#endif  // UTIL_VARIANT_HPP

src/map/vector_tile.cpp

@@ -12,7 +12,7 @@ VectorTile::VectorTile(pbf tile) {
     while (tile.next()) {
         if (tile.tag == 3) { // layer
             VectorTileLayer layer(tile.message());
-            layers.emplace(layer.name, layer);
+            layers.emplace(layer.name, std::forward<VectorTileLayer>(layer));
         } else {
             tile.skip();
         }
@@ -34,7 +34,7 @@ VectorTileLayer::VectorTileLayer(pbf layer) : data(layer) {
         } else if (layer.tag == 3) { // keys
             keys.emplace_back(layer.string());
         } else if (layer.tag == 4) { // values
-            values.emplace_back(parseValue(layer.message()));
+            values.emplace_back(std::move(parseValue(layer.message())));
         } else if (layer.tag == 5) { // extent
             extent = layer.varint();
         } else {

src/style/style.cpp

@@ -61,7 +61,7 @@ std::pair<std::string, BucketDescription> Style::parseBucket(pbf data) {
         }
     }
 
-    return { name, bucket };
+    return { name, std::forward<BucketDescription>(bucket) };
 }
 
 LayerDescription Style::parseLayer(pbf data) {

src/style/value.cpp

@@ -8,7 +8,7 @@ llmr::Value llmr::parseValue(pbf data) {
         case 1: // string_value
             return data.string();
         case 2: // float_value
-            return data.float32();
+            return static_cast<double>(data.float32());
         case 3: // double_value
             return data.float64();
         case 4: // int_value