|
@@ -32,6 +32,8 @@
|
|
|
|
|
|
/* static */ OpenGLBackend *OpenGLBackend::instance = nullptr;
|
|
|
|
|
|
GetOGLProcAddressProc GetOGLProcAddress;
|
|
|
|
|
|
/**
|
|
|
* Find a substring in a string made of space delimited elements. The substring
|
|
|
* has to match the complete element, partial matches don't count.
|
|
@@ -65,7 +67,31 @@ static const char *FindStringInExtension
|
|
|
*/
|
|
|
static bool IsOpenGLExtensionSupported(const char *extension)
|
|
|
{
|
|
|
return FindStringInExtensionList((const char *)glGetString(GL_EXTENSIONS), extension) != nullptr;
|
|
|
static PFNGLGETSTRINGIPROC glGetStringi = nullptr;
|
|
|
static bool glGetStringi_loaded = false;
|
|
|
|
|
|
/* Starting with OpenGL 3.0 the preferred API to get the extensions
|
|
|
* has changed. Try to load the required function once. */
|
|
|
if (!glGetStringi_loaded) {
|
|
|
if (IsOpenGLVersionAtLeast(3, 0)) glGetStringi = (PFNGLGETSTRINGIPROC)GetOGLProcAddress("glGetStringi");
|
|
|
glGetStringi_loaded = true;
|
|
|
}
|
|
|
|
|
|
if (glGetStringi != nullptr) {
|
|
|
/* New style: Each supported extension can be queried and compared independently. */
|
|
|
GLint num_exts;
|
|
|
glGetIntegerv(GL_NUM_EXTENSIONS, &num_exts);
|
|
|
|
|
|
for (GLint i = 0; i < num_exts; i++) {
|
|
|
const char *entry = (const char *)glGetStringi(GL_EXTENSIONS, i);
|
|
|
if (strcmp(entry, extension) == 0) return true;
|
|
|
}
|
|
|
} else {
|
|
|
/* Old style: A single, space-delimited string for all extensions. */
|
|
|
return FindStringInExtensionList((const char *)glGetString(GL_EXTENSIONS), extension) != nullptr;
|
|
|
}
|
|
|
|
|
|
return false;
|
|
|
}
|
|
|
|
|
|
static byte _gl_major_ver = 0; ///< Major OpenGL version.
|
|
@@ -78,7 +104,7 @@ static byte _gl_minor_ver = 0; ///< Mino
|
|
|
* @pre OpenGL was initialized.
|
|
|
* @return True if the OpenGL version is equal or higher than the requested one.
|
|
|
*/
|
|
|
static bool IsOpenGLVersionAtLeast(byte major, byte minor)
|
|
|
bool IsOpenGLVersionAtLeast(byte major, byte minor)
|
|
|
{
|
|
|
return (_gl_major_ver > major) || (_gl_major_ver == major && _gl_minor_ver >= minor);
|
|
|
}
|
|
@@ -86,11 +112,15 @@ static bool IsOpenGLVersionAtLeast(byte
|
|
|
|
|
|
/**
|
|
|
* Create and initialize the singleton back-end class.
|
|
|
* @param get_proc Callback to get an OpenGL function from the OS driver.
|
|
|
* @return nullptr on success, error message otherwise.
|
|
|
*/
|
|
|
/* static */ const char *OpenGLBackend::Create()
|
|
|
/* static */ const char *OpenGLBackend::Create(GetOGLProcAddressProc get_proc)
|
|
|
{
|
|
|
if (OpenGLBackend::instance != nullptr) OpenGLBackend::Destroy();
|
|
|
|
|
|
GetOGLProcAddress = get_proc;
|
|
|
|
|
|
OpenGLBackend::instance = new OpenGLBackend();
|
|
|
return OpenGLBackend::instance->Init();
|
|
|
}
|