src/dynapi/SDL_dynapi.c
author Sam Lantinga <slouken@libsdl.org>
Wed, 18 Oct 2017 08:52:04 -0700
changeset 11630 ad4b5d85edee
parent 11376 91e5e5a2cb71
child 11811 5d94cb6b24d3
permissions -rw-r--r--
Fixed bug 3821 - Allow SDL_CreateWindow and SDL_CreateRenderer with OpenGL ES 3.0 (GLES3) for Angle (Windows)

Carlos

Angle supports GLES3 but when using these functions (SDL_CreateWindow and SDL_CreateRenderer), defaults again to GLES2.0.

A current workaround (hack) to retrieve a GLES3.0 context with Angle is:

1) set

SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);

after InitSDL AND after calling SDL_CreateWindow (before SDL_CreateRenderer)

2) Comment lines 2032-2044 in SDL_render_gles2.c, funtion GLES2_CreateRenderer

window_flags = SDL_GetWindowFlags(window);
if (!(window_flags & SDL_WINDOW_OPENGL) ||
profile_mask != SDL_GL_CONTEXT_PROFILE_ES || major != RENDERER_CONTEXT_MAJOR || minor != RENDERER_CONTEXT_MINOR) {

changed_window = SDL_TRUE;
SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, RENDERER_CONTEXT_MAJOR);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, RENDERER_CONTEXT_MINOR);

if (SDL_RecreateWindow(window, window_flags | SDL_WINDOW_OPENGL) < 0) {
goto error;
}
}

This retrives a GLES3 context as confirmed using glGetString(GL_VERSION). This should be fixed by modifying a few if's.
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2017 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 */
    21 
    22 #include "SDL_config.h"
    23 #include "SDL_dynapi.h"
    24 
    25 #if SDL_DYNAMIC_API
    26 
    27 #if defined(__OS2__)
    28 #define INCL_DOS
    29 #define INCL_DOSERRORS
    30 #include <dos.h>
    31 #endif
    32 
    33 #include "SDL.h"
    34 
    35 /* These headers have system specific definitions, so aren't included above */
    36 #include "SDL_syswm.h"
    37 #include "SDL_vulkan.h"
    38 
    39 /* This is the version of the dynamic API. This doesn't match the SDL version
    40    and should not change until there's been a major revamp in API/ABI.
    41    So 2.0.5 adds functions over 2.0.4? This number doesn't change;
    42    the sizeof (jump_table) changes instead. But 2.1.0 changes how a function
    43    works in an incompatible way or removes a function? This number changes,
    44    since sizeof (jump_table) isn't sufficient anymore. It's likely
    45    we'll forget to bump every time we add a function, so this is the
    46    failsafe switch for major API change decisions. Respect it and use it
    47    sparingly. */
    48 #define SDL_DYNAPI_VERSION 1
    49 
    50 static void SDL_InitDynamicAPI(void);
    51 
    52 
    53 /* BE CAREFUL CALLING ANY SDL CODE IN HERE, IT WILL BLOW UP.
    54    Even self-contained stuff might call SDL_Error and break everything. */
    55 
    56 
    57 /* behold, the macro salsa! */
    58 
    59 /* !!! FIXME: ...disabled...until we write it.  :) */
    60 #define DISABLE_JUMP_MAGIC 1
    61 
    62 #if DISABLE_JUMP_MAGIC
    63 /* Can't use the macro for varargs nonsense. This is atrocious. */
    64 #define SDL_DYNAPI_VARARGS_LOGFN(_static, name, initcall, logname, prio) \
    65     _static void SDLCALL SDL_Log##logname##name(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...) { \
    66         va_list ap; initcall; va_start(ap, fmt); \
    67         jump_table.SDL_LogMessageV(category, SDL_LOG_PRIORITY_##prio, fmt, ap); \
    68         va_end(ap); \
    69     }
    70 
    71 #define SDL_DYNAPI_VARARGS(_static, name, initcall) \
    72     _static int SDLCALL SDL_SetError##name(SDL_PRINTF_FORMAT_STRING const char *fmt, ...) { \
    73         char buf[512]; /* !!! FIXME: dynamic allocation */ \
    74         va_list ap; initcall; va_start(ap, fmt); \
    75         jump_table.SDL_vsnprintf(buf, sizeof (buf), fmt, ap); \
    76         va_end(ap); \
    77         return jump_table.SDL_SetError("%s", buf); \
    78     } \
    79     _static int SDLCALL SDL_sscanf##name(const char *buf, SDL_SCANF_FORMAT_STRING const char *fmt, ...) { \
    80         int retval; va_list ap; initcall; va_start(ap, fmt); \
    81         retval = jump_table.SDL_vsscanf(buf, fmt, ap); \
    82         va_end(ap); \
    83         return retval; \
    84     } \
    85     _static int SDLCALL SDL_snprintf##name(SDL_OUT_Z_CAP(maxlen) char *buf, size_t maxlen, SDL_PRINTF_FORMAT_STRING const char *fmt, ...) { \
    86         int retval; va_list ap; initcall; va_start(ap, fmt); \
    87         retval = jump_table.SDL_vsnprintf(buf, maxlen, fmt, ap); \
    88         va_end(ap); \
    89         return retval; \
    90     } \
    91     _static void SDLCALL SDL_Log##name(SDL_PRINTF_FORMAT_STRING const char *fmt, ...) { \
    92         va_list ap; initcall; va_start(ap, fmt); \
    93         jump_table.SDL_LogMessageV(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO, fmt, ap); \
    94         va_end(ap); \
    95     } \
    96     _static void SDLCALL SDL_LogMessage##name(int category, SDL_LogPriority priority, SDL_PRINTF_FORMAT_STRING const char *fmt, ...) { \
    97         va_list ap; initcall; va_start(ap, fmt); \
    98         jump_table.SDL_LogMessageV(category, priority, fmt, ap); \
    99         va_end(ap); \
   100     } \
   101     SDL_DYNAPI_VARARGS_LOGFN(_static, name, initcall, Verbose, VERBOSE) \
   102     SDL_DYNAPI_VARARGS_LOGFN(_static, name, initcall, Debug, DEBUG) \
   103     SDL_DYNAPI_VARARGS_LOGFN(_static, name, initcall, Info, INFO) \
   104     SDL_DYNAPI_VARARGS_LOGFN(_static, name, initcall, Warn, WARN) \
   105     SDL_DYNAPI_VARARGS_LOGFN(_static, name, initcall, Error, ERROR) \
   106     SDL_DYNAPI_VARARGS_LOGFN(_static, name, initcall, Critical, CRITICAL)
   107 #endif
   108 
   109 
   110 /* Typedefs for function pointers for jump table, and predeclare funcs */
   111 /* The DEFAULT funcs will init jump table and then call real function. */
   112 /* The REAL funcs are the actual functions, name-mangled to not clash. */
   113 #define SDL_DYNAPI_PROC(rc,fn,params,args,ret) \
   114     typedef rc (SDLCALL *SDL_DYNAPIFN_##fn) params; \
   115     static rc SDLCALL fn##_DEFAULT params; \
   116     extern rc SDLCALL fn##_REAL params;
   117 #include "SDL_dynapi_procs.h"
   118 #undef SDL_DYNAPI_PROC
   119 
   120 /* The jump table! */
   121 typedef struct {
   122     #define SDL_DYNAPI_PROC(rc,fn,params,args,ret) SDL_DYNAPIFN_##fn fn;
   123     #include "SDL_dynapi_procs.h"
   124     #undef SDL_DYNAPI_PROC
   125 } SDL_DYNAPI_jump_table;
   126 
   127 /* Predeclare the default functions for initializing the jump table. */
   128 #define SDL_DYNAPI_PROC(rc,fn,params,args,ret) static rc SDLCALL fn##_DEFAULT params;
   129 #include "SDL_dynapi_procs.h"
   130 #undef SDL_DYNAPI_PROC
   131 
   132 /* The actual jump table. */
   133 static SDL_DYNAPI_jump_table jump_table = {
   134     #define SDL_DYNAPI_PROC(rc,fn,params,args,ret) fn##_DEFAULT,
   135     #include "SDL_dynapi_procs.h"
   136     #undef SDL_DYNAPI_PROC
   137 };
   138 
   139 /* Default functions init the function table then call right thing. */
   140 #if DISABLE_JUMP_MAGIC
   141 #define SDL_DYNAPI_PROC(rc,fn,params,args,ret) \
   142     static rc SDLCALL fn##_DEFAULT params { \
   143         SDL_InitDynamicAPI(); \
   144         ret jump_table.fn args; \
   145     }
   146 #define SDL_DYNAPI_PROC_NO_VARARGS 1
   147 #include "SDL_dynapi_procs.h"
   148 #undef SDL_DYNAPI_PROC
   149 #undef SDL_DYNAPI_PROC_NO_VARARGS
   150 SDL_DYNAPI_VARARGS(static, _DEFAULT, SDL_InitDynamicAPI())
   151 #else
   152 /* !!! FIXME: need the jump magic. */
   153 #error Write me.
   154 #endif
   155 
   156 /* Public API functions to jump into the jump table. */
   157 #if DISABLE_JUMP_MAGIC
   158 #define SDL_DYNAPI_PROC(rc,fn,params,args,ret) \
   159     rc SDLCALL fn params { ret jump_table.fn args; }
   160 #define SDL_DYNAPI_PROC_NO_VARARGS 1
   161 #include "SDL_dynapi_procs.h"
   162 #undef SDL_DYNAPI_PROC
   163 #undef SDL_DYNAPI_PROC_NO_VARARGS
   164 SDL_DYNAPI_VARARGS(,,)
   165 #else
   166 /* !!! FIXME: need the jump magic. */
   167 #error Write me.
   168 #endif
   169 
   170 
   171 
   172 /* Here's the exported entry point that fills in the jump table. */
   173 /*  Use specific types when an "int" might suffice to keep this sane. */
   174 typedef Sint32 (SDLCALL *SDL_DYNAPI_ENTRYFN)(Uint32 apiver, void *table, Uint32 tablesize);
   175 extern DECLSPEC Sint32 SDLCALL SDL_DYNAPI_entry(Uint32, void *, Uint32);
   176 
   177 Sint32
   178 SDL_DYNAPI_entry(Uint32 apiver, void *table, Uint32 tablesize)
   179 {
   180     SDL_DYNAPI_jump_table *output_jump_table = (SDL_DYNAPI_jump_table *) table;
   181 
   182     if (apiver != SDL_DYNAPI_VERSION) {
   183         /* !!! FIXME: can maybe handle older versions? */
   184         return -1;  /* not compatible. */
   185     } else if (tablesize > sizeof (jump_table)) {
   186         return -1;  /* newer version of SDL with functions we can't provide. */
   187     }
   188 
   189     /* Init our jump table first. */
   190     #define SDL_DYNAPI_PROC(rc,fn,params,args,ret) jump_table.fn = fn##_REAL;
   191     #include "SDL_dynapi_procs.h"
   192     #undef SDL_DYNAPI_PROC
   193 
   194     /* Then the external table... */
   195     if (output_jump_table != &jump_table) {
   196         jump_table.SDL_memcpy(output_jump_table, &jump_table, tablesize);
   197     }
   198 
   199     /* Safe to call SDL functions now; jump table is initialized! */
   200 
   201     return 0;  /* success! */
   202 }
   203 
   204 
   205 /* Obviously we can't use SDL_LoadObject() to load SDL.  :)  */
   206 /* Also obviously, we never close the loaded library. */
   207 #if defined(WIN32) || defined(_WIN32) || defined(__CYGWIN__)
   208 #ifndef WIN32_LEAN_AND_MEAN
   209 #define WIN32_LEAN_AND_MEAN 1
   210 #endif
   211 #include <windows.h>
   212 static SDL_INLINE void *get_sdlapi_entry(const char *fname, const char *sym)
   213 {
   214     HANDLE lib = LoadLibraryA(fname);
   215     void *retval = NULL;
   216     if (lib) {
   217         retval = GetProcAddress(lib, sym);
   218         if (retval == NULL) {
   219             FreeLibrary(lib);
   220         }
   221     }
   222     return retval;
   223 }
   224 
   225 #elif defined(unix) || defined(__unix__) || defined(__APPLE__) || defined(__HAIKU__) || defined(__QNX__)
   226 #include <dlfcn.h>
   227 static SDL_INLINE void *get_sdlapi_entry(const char *fname, const char *sym)
   228 {
   229     void *lib = dlopen(fname, RTLD_NOW | RTLD_LOCAL);
   230     void *retval = NULL;
   231     if (lib != NULL) {
   232         retval = dlsym(lib, sym);
   233         if (retval == NULL) {
   234             dlclose(lib);
   235         }
   236     }
   237     return retval;
   238 }
   239 
   240 #elif defined(__OS2__)
   241 static SDL_INLINE void *get_sdlapi_entry(const char *fname, const char *sym)
   242 {
   243     HMODULE hmodule;
   244     PFN retval = NULL;
   245     char error[256];
   246     if (DosLoadModule(&error, sizeof(error), fname, &hmodule) == NO_ERROR) {
   247         if (DosQueryProcAddr(hmodule, 0, sym, &retval) != NO_ERROR) {
   248             DosFreeModule(hmodule);
   249         }
   250     }
   251     return (void *) retval;
   252 }
   253 
   254 #else
   255 #error Please define your platform.
   256 #endif
   257 
   258 
   259 static void
   260 SDL_InitDynamicAPILocked(void)
   261 {
   262     const char *libname = SDL_getenv_REAL("SDL_DYNAMIC_API");
   263     SDL_DYNAPI_ENTRYFN entry = SDL_DYNAPI_entry;  /* funcs from here by default. */
   264 
   265     if (libname) {
   266         entry = (SDL_DYNAPI_ENTRYFN) get_sdlapi_entry(libname, "SDL_DYNAPI_entry");
   267         if (!entry) {
   268             /* !!! FIXME: fail to startup here instead? */
   269             /* !!! FIXME: definitely warn user. */
   270             /* Just fill in the function pointers from this library. */
   271             entry = SDL_DYNAPI_entry;
   272         }
   273     }
   274 
   275     if (entry(SDL_DYNAPI_VERSION, &jump_table, sizeof (jump_table)) < 0) {
   276         /* !!! FIXME: fail to startup here instead? */
   277         /* !!! FIXME: definitely warn user. */
   278         /* Just fill in the function pointers from this library. */
   279         if (entry != SDL_DYNAPI_entry) {
   280             if (!SDL_DYNAPI_entry(SDL_DYNAPI_VERSION, &jump_table, sizeof (jump_table))) {
   281                 /* !!! FIXME: now we're screwed. Should definitely abort now. */
   282             }
   283         }
   284     }
   285 
   286     /* we intentionally never close the newly-loaded lib, of course. */
   287 }
   288 
   289 static void
   290 SDL_InitDynamicAPI(void)
   291 {
   292     /* So the theory is that every function in the jump table defaults to
   293      *  calling this function, and then replaces itself with a version that
   294      *  doesn't call this function anymore. But it's possible that, in an
   295      *  extreme corner case, you can have a second thread hit this function
   296      *  while the jump table is being initialized by the first.
   297      * In this case, a spinlock is really painful compared to what spinlocks
   298      *  _should_ be used for, but this would only happen once, and should be
   299      *  insanely rare, as you would have to spin a thread outside of SDL (as
   300      *  SDL_CreateThread() would also call this function before building the
   301      *  new thread).
   302      */
   303     static SDL_bool already_initialized = SDL_FALSE;
   304 
   305     /* SDL_AtomicLock calls SDL mutex functions to emulate if
   306        SDL_ATOMIC_DISABLED, which we can't do here, so in such a
   307        configuration, you're on your own. */
   308     #if !SDL_ATOMIC_DISABLED
   309     static SDL_SpinLock lock = 0;
   310     SDL_AtomicLock_REAL(&lock);
   311     #endif
   312 
   313     if (!already_initialized) {
   314         SDL_InitDynamicAPILocked();
   315         already_initialized = SDL_TRUE;
   316     }
   317 
   318     #if !SDL_ATOMIC_DISABLED
   319     SDL_AtomicUnlock_REAL(&lock);
   320     #endif
   321 }
   322 
   323 #endif  /* SDL_DYNAMIC_API */
   324 
   325 /* vi: set ts=4 sw=4 expandtab: */