Implement wrapper for SDL_image init/deinit

Fixes #21

CMakeLists.txt

@@ -98,6 +98,7 @@ SET(LIBRARY_SOURCES
 	SDL2pp/Rect.cc
 	SDL2pp/Renderer.cc
 	SDL2pp/SDL.cc
+	SDL2pp/SDLImage.cc
 	SDL2pp/Texture.cc
 	SDL2pp/TextureLock.cc
 	SDL2pp/Wav.cc
@@ -116,6 +117,7 @@ SET(LIBRARY_HEADERS
 	SDL2pp/Renderer.hh
 	SDL2pp/SDL.hh
 	SDL2pp/SDL2pp.hh
+	SDL2pp/SDLImage.hh
 	SDL2pp/StreamRWops.hh
 	SDL2pp/Texture.hh
 	SDL2pp/Wav.hh

SDL2pp/Exception.hh

@@ -43,6 +43,13 @@ namespace SDL2pp {
 /// what() usually contains a name of SDL2 function which failed,
 /// e.g. "SDL_Init() failed"
 ///
+/// Note: this Exception object is used to report errors from
+/// SDL2 satellite libraries (SDL_image, SDL_mixer, SDL_ttf)
+/// as well. Though they use their own error handling functions
+/// (IMG_GetError, Mix_GetError, TTF_GetError), those are (currently)
+/// just macros pointing to SDL_GetError. We currently rely on that.
+/// If that changes, we'll need a hierarchy of specific exceptions.
+///
 /// Usage example:
 /// \code
 /// {

SDL2pp/SDL2pp.hh

@@ -95,4 +95,12 @@
 #include <SDL2pp/ContainerRWops.hh>
 #include <SDL2pp/StreamRWops.hh>
 
+////////////////////////////////////////////////////////////
+/// \defgroup image SDL_image
+///
+/// \brief Functions that are specific to SDL_image library
+///
+////////////////////////////////////////////////////////////
+#include <SDL2pp/SDLImage.hh>
+
 #endif

SDL2pp/SDLImage.cc

@@ -0,0 +1,49 @@
+/*
+  libSDL2pp - C++11 bindings/wrapper for SDL2
+  Copyright (C) 2014 Dmitry Marakasov <amdmi3@amdmi3.ru>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include <SDL2/SDL_image.h>
+
+#include <SDL2pp/SDLImage.hh>
+#include <SDL2pp/Exception.hh>
+
+namespace SDL2pp {
+
+SDLImage::SDLImage(int flags) {
+	if ((IMG_Init(flags) & flags) != flags)
+		throw Exception("IMG_Init failed");
+}
+
+SDLImage::~SDLImage() {
+	IMG_Quit();
+}
+
+int SDLImage::InitMore(int flags) {
+	int ret;
+	if (((ret = IMG_Init(flags)) & flags) != flags)
+		throw Exception("IMG_Init failed");
+	return ret;
+}
+
+int SDLImage::GetInitFlags() {
+	return IMG_Init(0);
+}
+
+}

SDL2pp/SDLImage.hh

@@ -0,0 +1,106 @@
+/*
+  libSDL2pp - C++11 bindings/wrapper for SDL2
+  Copyright (C) 2014 Dmitry Marakasov <amdmi3@amdmi3.ru>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifndef SDL2PP_SDLIMAGE_HH
+#define SDL2PP_SDLIMAGE_HH
+
+namespace SDL2pp {
+
+////////////////////////////////////////////////////////////
+/// \brief Object taking care of SDL_image library (de-)initialization
+///
+/// \ingroup image
+///
+/// \headerfile SDL2pp/SDLImage.hh
+///
+/// Though it's possible to use SDL_image without initializing it,
+/// library provide initialization/deinitialization functions to
+/// be able to preload libraries for specific file format support
+/// (png, jpeg or tiff) beforehand. In SDL2pp, this is handled by
+/// this class.
+///
+/// Usage example:
+/// \code
+/// int main() {
+///     SDL2pp::SDL sdl(SDL_INIT_VIDEO);
+///     SDL2pp::SDLImage image(IMG_INIT_PNG);
+///
+///     // use SDL_image functions
+///     SDL2pp::Texture t("/path/to/file.png");
+///
+///     // SDL_image library is automatically deinitialized before exit
+///     return 0;
+/// }
+/// \endcode
+///
+////////////////////////////////////////////////////////////
+class SDLImage {
+public:
+	////////////////////////////////////////////////////////////
+	/// \brief Initializes SDL_image library
+	///
+	/// \param flags Flags to pass to IMG_Init()
+	///
+	/// \throws SDL2pp::Exception
+	///
+	/// \see https://www.libsdl.org/projects/SDL_image/docs/SDL_image.html#SEC8
+	///
+	////////////////////////////////////////////////////////////
+	SDLImage(int flags);
+
+	////////////////////////////////////////////////////////////
+	/// \brief Destructor, deinitializes SDL_image library
+	///
+	/// \see https://www.libsdl.org/projects/SDL_image/docs/SDL_image.html#SEC9
+	///
+	////////////////////////////////////////////////////////////
+	virtual ~SDLImage();
+
+	////////////////////////////////////////////////////////////
+	/// \brief Try to init more SDL_image formats
+	///
+	/// \param flags Flags to pass to IMG_Init()
+	///
+	/// \throws SDL2pp::Exception
+	///
+	/// \see https://www.libsdl.org/projects/SDL_image/docs/SDL_image.html#SEC8
+	///
+	////////////////////////////////////////////////////////////
+	int InitMore(int flags);
+
+	////////////////////////////////////////////////////////////
+	/// \brief Get mask of initialized SDL_image formats
+	///
+	/// \see https://www.libsdl.org/projects/SDL_image/docs/SDL_image.html#SEC8
+	///
+	////////////////////////////////////////////////////////////
+	int GetInitFlags();
+
+	// Deleted copy/move constructors and assignments
+	SDLImage(const SDLImage& other) = delete;
+	SDLImage(SDLImage&& other) = delete;
+	SDLImage& operator=(const SDLImage& other) = delete;
+	SDLImage& operator=(SDLImage&& other) = delete;
+};
+
+}
+
+#endif

examples/image.cc

@@ -22,8 +22,10 @@
 #include <iostream>
 
 #include <SDL2/SDL.h>
+#include <SDL2/SDL_image.h>
 
 #include <SDL2pp/SDL.hh>
+#include <SDL2pp/SDLImage.hh>
 #include <SDL2pp/Window.hh>
 #include <SDL2pp/Renderer.hh>
 #include <SDL2pp/Texture.hh>
@@ -33,6 +35,7 @@ using namespace SDL2pp;
 
 int Run() {
 	SDL sdl(SDL_INIT_VIDEO);
+	SDLImage image(IMG_INIT_PNG); // optional
 	Window window("libSDL2pp demo: loading", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 640, 480, SDL_WINDOW_RESIZABLE);
 	Renderer render(window, -1, SDL_RENDERER_ACCELERATED);