Add Music ctors from RWops based on undocumented SDL_mixer functions

Fixes #92

CHANGES.md

@@ -5,6 +5,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 ## 0.14.0 - unreleased
 ### Added
 * ```Window::GetOpacity()``` and ```Window()::SetOpacity()``` wrappers for functions appeared in SDL 2.0.5
+* ```Music``` RWops constructors based on undocumented SDL_mixer functions
 
 ### Changed
 * libSDL2pp now follows SDL2 include path conventions, finding and using SDL2 headers without SDL2/ prefix

SDL2pp/Music.cc

@@ -21,8 +21,9 @@
 
 #include <cassert>
 
-#include <SDL2pp/Music.hh>
 #include <SDL2pp/Exception.hh>
+#include <SDL2pp/Music.hh>
+#include <SDL2pp/RWops.hh>
 
 namespace SDL2pp {
 
@@ -35,6 +36,16 @@ Music::Music(const std::string& file) {
 		throw Exception("Mix_LoadMUS");
 }
 
+Music::Music(RWops& rwops) {
+	if ((music_ = Mix_LoadMUS_RW(rwops.Get(), 0)) == nullptr)
+		throw Exception("Mix_LoadMUS_RW");
+}
+
+Music::Music(RWops& rwops, Mix_MusicType type) {
+	if ((music_ = Mix_LoadMUSType_RW(rwops.Get(), type, 0)) == nullptr)
+		throw Exception("Mix_LoadMUSType_RW");
+}
+
 Music::~Music() {
 	if (music_ != nullptr)
 		Mix_FreeMusic(music_);

SDL2pp/Music.hh

@@ -30,6 +30,8 @@
 
 namespace SDL2pp {
 
+class RWops;
+
 ////////////////////////////////////////////////////////////
 /// \brief %Music data
 ///
@@ -63,6 +65,33 @@ public:
 	////////////////////////////////////////////////////////////
 	explicit Music(const std::string& file);
 
+	////////////////////////////////////////////////////////////
+	/// \brief Load music using RWops
+	///
+	/// This uses undocumented SDL_Mixer function. Comment
+	/// in SDL_mixer.h suggests it's only indended to work with
+	/// Ogg and MikMod.
+	///
+	/// \param[in] rwops SDL2pp::RWops used to access music data
+	///
+	/// \throws SDL2pp::Exception
+	///
+	////////////////////////////////////////////////////////////
+	explicit Music(RWops& rwops);
+
+	////////////////////////////////////////////////////////////
+	/// \brief Load music using RWops
+	///
+	/// This uses undocumented SDL_Mixer function.
+	///
+	/// \param[in] rwops SDL2pp::RWops used to access music data
+	/// \param[in] type Music type to load
+	///
+	/// \throws SDL2pp::Exception
+	///
+	////////////////////////////////////////////////////////////
+	Music(RWops& rwops, Mix_MusicType type);
+
 	////////////////////////////////////////////////////////////
 	/// \brief Destructor
 	///