X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=blobdiff_plain;f=source%2Fextension.h;h=e6c2aca045491e4a23005b87ac35d60c5cab3e64;hp=4072869cc25662d8c76fe2d4ab94c5700515f2a3;hb=6afbace895a7bbcf216ab8e48280ea0303ab5892;hpb=485315ca65cb40f33253008a79b0933997bd74f5

diff --git a/source/extension.h b/source/extension.h
index 4072869c..e6c2aca0 100644
--- a/source/extension.h
+++ b/source/extension.h
@@ -12,54 +12,52 @@ struct Version
 	unsigned short minor;
 };
 
-typedef void ExtFunc();
 
-/**
-Indicates whether an extension is supported.  If this returns true, the
-functions of that extension are safe to use.
-*/
-bool is_supported(const std::string &);
+class Extension
+{
+public:
+	enum SupportLevel
+	{
+		UNSUPPORTED,
+		EXTENSION,
+		CORE
+	};
 
-/**
-Checks that an extension is supported and throws if it isn't.
-*/
-void require_extension(const std::string &);
+	typedef SupportLevel (*InitFunc)();
 
-/**
-RAII version of require_extension.  Useful as a static local variable.
-*/
-struct RequireExtension
-{
-	RequireExtension(const std::string &e) { require_extension(e); }
-};
+private:
+	const char *name;
+	InitFunc init_func;
+	mutable bool init_done;
+	mutable SupportLevel support;
 
-/**
-Returns the OpenGL version number, as reported by the implementation.
-Functions up to the returned version are safe to use.
-*/
-const Version &get_gl_version();
+public:
+	Extension(const char *, InitFunc);
 
-/**
-Indicates whether the OpenGL version is at least a.b.
-*/
-bool is_version_at_least(unsigned a, unsigned b);
+	const char *get_name() const { return name; }
+	operator bool() const;
+};
 
-/**
-Checks that the OpenGL version is at least a.b and throws if it isn't.
-*/
-void require_version(unsigned a, unsigned b);
 
-/**
-RAII version of require_version.  Useful as a static local variable.
-*/
-struct RequireVersion
+struct Require
 {
-	RequireVersion(unsigned a, unsigned b) { require_version(a, b); }
+	Require(const Extension &);
 };
 
-/**
-Returns the address of an extension function.  Only indended for internal use.
-*/
+
+typedef void ExtFunc();
+
+/** Indicates whether an extension is supported. */
+bool is_supported(const std::string &);
+
+/** Returns the OpenGL version number, as reported by the implementation. */
+const Version &get_gl_version();
+
+/** Indicates whether the OpenGL version is at least a.b. */
+bool is_version_at_least(unsigned a, unsigned b);
+
+/** Returns the address of an extension function.  Only indended for internal
+use. */
 ExtFunc *get_proc_address(const std::string &);
 
 } // namespace GL