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Diffstat (limited to 'glew/auto/src/glew_init_gl.c')
-rw-r--r--glew/auto/src/glew_init_gl.c209
1 files changed, 209 insertions, 0 deletions
diff --git a/glew/auto/src/glew_init_gl.c b/glew/auto/src/glew_init_gl.c
new file mode 100644
index 0000000..53a5885
--- /dev/null
+++ b/glew/auto/src/glew_init_gl.c
@@ -0,0 +1,209 @@
+/* ------------------------------------------------------------------------- */
+
+static int _glewExtensionCompare(const char *s1, const char *s2)
+{
+ /* http://www.chanduthedev.com/2012/07/strcmp-implementation-in-c.html */
+ while (*s1 || *s2)
+ {
+ if (*s1 > *s2)
+ return 1;
+ if (*s1 < *s2)
+ return -1;
+ s1++;
+ s2++;
+ }
+ return 0;
+}
+
+static ptrdiff_t _glewBsearchExtension(const char* name)
+{
+ ptrdiff_t lo = 0, hi = sizeof(_glewExtensionLookup) / sizeof(char*) - 2;
+
+ while (lo <= hi)
+ {
+ ptrdiff_t mid = (lo + hi) / 2;
+ const int cmp = _glewExtensionCompare(name, _glewExtensionLookup[mid]);
+ if (cmp < 0) hi = mid - 1;
+ else if (cmp > 0) lo = mid + 1;
+ else return mid;
+ }
+ return -1;
+}
+
+static GLboolean *_glewGetExtensionString(const char *name)
+{
+ ptrdiff_t n = _glewBsearchExtension(name);
+ if (n >= 0) return &_glewExtensionString[n];
+ return NULL;
+}
+
+static GLboolean *_glewGetExtensionEnable(const char *name)
+{
+ ptrdiff_t n = _glewBsearchExtension(name);
+ if (n >= 0) return _glewExtensionEnabled[n];
+ return NULL;
+}
+
+static const char *_glewNextSpace(const char *i)
+{
+ const char *j = i;
+ if (j)
+ while (*j!=' ' && *j) ++j;
+ return j;
+}
+
+static const char *_glewNextNonSpace(const char *i)
+{
+ const char *j = i;
+ if (j)
+ while (*j==' ') ++j;
+ return j;
+}
+
+GLboolean GLEWAPIENTRY glewGetExtension (const char* name)
+{
+ GLboolean *enable = _glewGetExtensionString(name);
+ if (enable)
+ return *enable;
+ return GL_FALSE;
+}
+
+/* ------------------------------------------------------------------------- */
+
+typedef const GLubyte* (GLAPIENTRY * PFNGLGETSTRINGPROC) (GLenum name);
+typedef void (GLAPIENTRY * PFNGLGETINTEGERVPROC) (GLenum pname, GLint *params);
+
+GLenum GLEWAPIENTRY glewContextInit (void)
+{
+ PFNGLGETSTRINGPROC getString;
+ const GLubyte* s;
+ GLuint dot;
+ GLint major, minor;
+
+ #ifdef _WIN32
+ getString = glGetString;
+ #else
+ getString = (PFNGLGETSTRINGPROC) glewGetProcAddress((const GLubyte*)"glGetString");
+ if (!getString)
+ return GLEW_ERROR_NO_GL_VERSION;
+ #endif
+
+ /* query opengl version */
+ s = getString(GL_VERSION);
+ dot = _glewStrCLen(s, '.');
+ if (dot == 0)
+ return GLEW_ERROR_NO_GL_VERSION;
+
+ major = s[dot-1]-'0';
+ minor = s[dot+1]-'0';
+
+ if (minor < 0 || minor > 9)
+ minor = 0;
+ if (major<0 || major>9)
+ return GLEW_ERROR_NO_GL_VERSION;
+
+ if (major == 1 && minor == 0)
+ {
+ return GLEW_ERROR_GL_VERSION_10_ONLY;
+ }
+ else
+ {
+ GLEW_VERSION_4_6 = ( major > 4 ) || ( major == 4 && minor >= 6 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_4_5 = GLEW_VERSION_4_6 == GL_TRUE || ( major == 4 && minor >= 5 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_4_4 = GLEW_VERSION_4_5 == GL_TRUE || ( major == 4 && minor >= 4 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_4_3 = GLEW_VERSION_4_4 == GL_TRUE || ( major == 4 && minor >= 3 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_4_2 = GLEW_VERSION_4_3 == GL_TRUE || ( major == 4 && minor >= 2 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_4_1 = GLEW_VERSION_4_2 == GL_TRUE || ( major == 4 && minor >= 1 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_4_0 = GLEW_VERSION_4_1 == GL_TRUE || ( major == 4 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_3_3 = GLEW_VERSION_4_0 == GL_TRUE || ( major == 3 && minor >= 3 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_3_2 = GLEW_VERSION_3_3 == GL_TRUE || ( major == 3 && minor >= 2 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_3_1 = GLEW_VERSION_3_2 == GL_TRUE || ( major == 3 && minor >= 1 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_3_0 = GLEW_VERSION_3_1 == GL_TRUE || ( major == 3 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_2_1 = GLEW_VERSION_3_0 == GL_TRUE || ( major == 2 && minor >= 1 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_2_0 = GLEW_VERSION_2_1 == GL_TRUE || ( major == 2 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_1_5 = GLEW_VERSION_2_0 == GL_TRUE || ( major == 1 && minor >= 5 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_1_4 = GLEW_VERSION_1_5 == GL_TRUE || ( major == 1 && minor >= 4 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_1_3 = GLEW_VERSION_1_4 == GL_TRUE || ( major == 1 && minor >= 3 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_1_2_1 = GLEW_VERSION_1_3 == GL_TRUE ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_1_2 = GLEW_VERSION_1_2_1 == GL_TRUE || ( major == 1 && minor >= 2 ) ? GL_TRUE : GL_FALSE;
+ GLEW_VERSION_1_1 = GLEW_VERSION_1_2 == GL_TRUE || ( major == 1 && minor >= 1 ) ? GL_TRUE : GL_FALSE;
+ }
+
+ {
+ size_t i;
+ for (i = 0; i < sizeof(_glewExtensionString) / sizeof(_glewExtensionString[0]); ++i)
+ _glewExtensionString[i] = GL_FALSE;
+ }
+
+ if (GLEW_VERSION_3_0)
+ {
+ GLint n = 0;
+ GLint i;
+ PFNGLGETINTEGERVPROC getIntegerv;
+ PFNGLGETSTRINGIPROC getStringi;
+ const char *ext;
+ GLboolean *enable;
+
+ #ifdef _WIN32
+ getIntegerv = glGetIntegerv;
+ #else
+ getIntegerv = (PFNGLGETINTEGERVPROC) glewGetProcAddress((const GLubyte*)"glGetIntegerv");
+ #endif
+
+ if (getIntegerv)
+ getIntegerv(GL_NUM_EXTENSIONS, &n);
+
+ /* glGetStringi is OpenGL 3.0 */
+ getStringi = (PFNGLGETSTRINGIPROC) glewGetProcAddress((const GLubyte*)"glGetStringi");
+ if (getStringi)
+ for (i = 0; i<n; ++i)
+ {
+ ext = (const char *) getStringi(GL_EXTENSIONS, i);
+
+ /* Based on extension string(s), glewGetExtension purposes */
+ enable = _glewGetExtensionString(ext);
+ if (enable)
+ *enable = GL_TRUE;
+
+ /* Based on extension string(s), experimental mode, glewIsSupported purposes */
+ enable = _glewGetExtensionEnable(ext);
+ if (enable)
+ *enable = GL_TRUE;
+ }
+ }
+ else
+ {
+ const char *extensions;
+ const char *end;
+ const char *i;
+ const char *j;
+ char ext[128];
+ GLboolean *enable;
+
+ extensions = (const char *) getString(GL_EXTENSIONS);
+
+ if (extensions)
+ {
+ end = extensions + _glewStrLen((const GLubyte *) extensions);
+ for (i=extensions; i<end; i = j + 1)
+ {
+ i = _glewNextNonSpace(i);
+ j = _glewNextSpace(i);
+
+ /* Copy extension into NUL terminated string */
+ if (j-i >= (ptrdiff_t) sizeof(ext))
+ continue;
+ _glewStrCopy(ext, i, ' ');
+
+ /* Based on extension string(s), glewGetExtension purposes */
+ enable = _glewGetExtensionString(ext);
+ if (enable)
+ *enable = GL_TRUE;
+
+ /* Based on extension string(s), experimental mode, glewIsSupported purposes */
+ enable = _glewGetExtensionEnable(ext);
+ if (enable)
+ *enable = GL_TRUE;
+ }
+ }
+ }
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