text: /*
   Implementation notes:
  
   - An OOP style is used where each "class" is made up of a struct and a number of functions prefixed with the struct name.
  
   - struct fields that are const are readonly. Either they are set in a create function and can never be changed, or they can only
   be changed by calling a function.
  
   - Inheritance is done using a struct field named "super" as the first field, allowing the struct to be cast to its "super class".
   This works because a pointer to a struct is guaranteed to be a pointer to the first struct field.
  
   - Classes intended for inheritance provide init/deinit functions which subclasses must call in their create/dispose functions.
  
   - Polymorphism is done by a base class providing function pointers in its init function. The public API delegates to this
   function.
  
   - Subclasses do not provide a dispose function, instead the base class' dispose function should be used, which will delegate to
   a dispose function pointer.
  
   - Classes not designed for inheritance cannot be extended because they may use an internal subclass to hide private data and don't
   expose function pointers.
  
   - The public API hides implementation details, such as init/deinit functions. An internal API is exposed by extension.h to allow
   classes to be extended. Internal functions begin with underscore (_).
  
   - OOP in C tends to lose type safety. Macros for casting are provided in extension.h to give context for why a cast is being done.
  
   - If SPINE_SHORT_NAMES is defined, the "sp" prefix for all class names is optional.
   */
  
  #ifndef SPINE_EXTENSION_H_
  #define SPINE_EXTENSION_H_
  
  /* All allocation uses these. */
  #define MALLOC(TYPE,COUNT) ((TYPE*)_malloc(sizeof(TYPE) * (COUNT), __FILE__, __LINE__))
  #define CALLOC(TYPE,COUNT) ((TYPE*)_calloc(COUNT, sizeof(TYPE), __FILE__, __LINE__))
  #define NEW(TYPE) CALLOC(TYPE,1)
  
  /* Gets the direct super class. Type safe. */
  #define SUPER(VALUE) (&VALUE->super)
  
  /* Cast to a super class. Not type safe, use with care. Prefer SUPER() where possible. */
  #define SUPER_CAST(TYPE,VALUE) ((TYPE*)VALUE)
  
  /* Cast to a sub class. Not type safe, use with care. */
  #define SUB_CAST(TYPE,VALUE) ((TYPE*)VALUE)
  
  /* Casts away const. Can be used as an lvalue. Not type safe, use with care. */
  #define CONST_CAST(TYPE,VALUE) (*(TYPE*)&VALUE)
  
  /* Gets the vtable for the specified type. Not type safe, use with care. */
  #define VTABLE(TYPE,VALUE) ((_##TYPE##Vtable*)((TYPE*)VALUE)->vtable)
  
  /* Frees memory. Can be used on const types. */
  #define FREE(VALUE) _free((void*)VALUE)
  
  /* Allocates a new char[], assigns it to TO, and copies FROM to it. Can be used on const types. */
  #define MALLOC_STR(TO,FROM) strcpy(CONST_CAST(char*, TO) = (char*)MALLOC(char, strlen(FROM) + 1), FROM)
  
  #define PI 3.1415926535897932385f
  #define DEG_RAD (PI / 180)
  #define RAD_DEG (180 / PI)
  
  #ifdef __STDC_VERSION__
  #define FMOD(A,B) fmodf(A, B)
  #define ATAN2(A,B) atan2f(A, B)
  #define SIN(A) sinf(A)
  #define COS(A) cosf(A)
  #define SQRT(A) sqrtf(A)
  #define ACOS(A) acosf(A)
  #else
  #define FMOD(A,B) (float)fmod(A, B)
  #define ATAN2(A,B) (float)atan2(A, B)
  #define COS(A) (float)cos(A)
  #define SIN(A) (float)sin(A)
  #define SQRT(A) (float)sqrt(A)
  #define ACOS(A) (float)acos(A)
  #endif
  
  #include <stdlib.h>
  #include <string.h>
  #include <math.h>
  #include <spine/Skeleton.h>
  #include <spine/Animation.h>
  #include <spine/Atlas.h>
  #include <spine/AttachmentLoader.h>
  #include <spine/RegionAttachment.h>
  #include <spine/MeshAttachment.h>
  #include <spine/SkinnedMeshAttachment.h>
  #include <spine/BoundingBoxAttachment.h>
  #include <spine/AnimationState.h>
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /*
   * Functions that must be implemented:
   */
  
  void _spAtlasPage_createTexture (spAtlasPage* self, const char* path);
  void _spAtlasPage_disposeTexture (spAtlasPage* self);
  char* _spUtil_readFile (const char* path, int* length);
  
  #ifdef SPINE_SHORT_NAMES
  #define _AtlasPage_createTexture(...) _spAtlasPage_createTexture(__VA_ARGS__)
  #define _AtlasPage_disposeTexture(...) _spAtlasPage_disposeTexture(__VA_ARGS__)
  #define _Util_readFile(...) _spUtil_readFile(__VA_ARGS__)
  #endif
  
  /*
   * Internal API available for extension:
   */
  
  void* _malloc (size_t size, const char* file, int line);
  void* _calloc (size_t num, size_t size, const char* file, int line);
  void _free (void* ptr);
  
  void _setMalloc (void* (*_malloc) (size_t size));
  void _setDebugMalloc (void* (*_malloc) (size_t size, const char* file, int line));
  void _setFree (void (*_free) (void* ptr));
  
  char* _readFile (const char* path, int* length);
  
  /**/
  
  typedef struct _spAnimationState {
  	spAnimationState super;
  	spEvent** events;
  
  	spTrackEntry* (*createTrackEntry) (spAnimationState* self);
  	void (*disposeTrackEntry) (spTrackEntry* entry);
  
  #ifdef __cplusplus
  	_spAnimationState() :
  		super(),
  		events(0),
  		createTrackEntry(0),
  		disposeTrackEntry(0) {
  	}
  #endif
  } _spAnimationState;
  
  spTrackEntry* _spTrackEntry_create (spAnimationState* self);
  void _spTrackEntry_dispose (spTrackEntry* self);
  
  /**/
  
  void _spAttachmentLoader_init (spAttachmentLoader* self, /**/
  void (*dispose) (spAttachmentLoader* self), /**/
  		spAttachment* (*newAttachment) (spAttachmentLoader* self, spSkin* skin, spAttachmentType type, const char* name,
  				const char* path));
  void _spAttachmentLoader_deinit (spAttachmentLoader* self);
  void _spAttachmentLoader_setError (spAttachmentLoader* self, const char* error1, const char* error2);
  void _spAttachmentLoader_setUnknownTypeError (spAttachmentLoader* self, spAttachmentType type);
  
  #ifdef SPINE_SHORT_NAMES
  #define _AttachmentLoader_init(...) _spAttachmentLoader_init(__VA_ARGS__)
  #define _AttachmentLoader_deinit(...) _spAttachmentLoader_deinit(__VA_ARGS__)
  #define _AttachmentLoader_setError(...) _spAttachmentLoader_setError(__VA_ARGS__)
  #define _AttachmentLoader_setUnknownTypeError(...) _spAttachmentLoader_setUnknownTypeError(__VA_ARGS__)
  #endif
  
  /**/
  
  void _spAttachment_init (spAttachment* self, const char* name, spAttachmentType type, /**/
  void (*dispose) (spAttachment* self));
  void _spAttachment_deinit (spAttachment* self);
  
  #ifdef SPINE_SHORT_NAMES
  #define _Attachment_init(...) _spAttachment_init(__VA_ARGS__)
  #define _Attachment_deinit(...) _spAttachment_deinit(__VA_ARGS__)
  #endif
  
  /**/
  
  void _spTimeline_init (spTimeline* self, spTimelineType type, /**/
  void (*dispose) (spTimeline* self), /**/
  		void (*apply) (const spTimeline* self, spSkeleton* skeleton, float lastTime, float time, spEvent** firedEvents,
  				int* eventsCount, float alpha));
  void _spTimeline_deinit (spTimeline* self);
  
  #ifdef SPINE_SHORT_NAMES
  #define _Timeline_init(...) _spTimeline_init(__VA_ARGS__)
  #define _Timeline_deinit(...) _spTimeline_deinit(__VA_ARGS__)
  #endif
  
  /**/
  
  void _spCurveTimeline_init (spCurveTimeline* self, spTimelineType type, int framesCount, /**/
  void (*dispose) (spTimeline* self), /**/
  		void (*apply) (const spTimeline* self, spSkeleton* skeleton, float lastTime, float time, spEvent** firedEvents,
  				int* eventsCount, float alpha));
  void _spCurveTimeline_deinit (spCurveTimeline* self);
  
  #ifdef SPINE_SHORT_NAMES
  #define _CurveTimeline_init(...) _spCurveTimeline_init(__VA_ARGS__)
  #define _CurveTimeline_deinit(...) _spCurveTimeline_deinit(__VA_ARGS__)
  #endif
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* SPINE_EXTENSION_H_ */
  