Move all OpenGL-specific code to a separate directory

[libs/gl.git] / source / backends / opengl / extension.h

diff --git a/source/backends/opengl/extension.h b/source/backends/opengl/extension.h
new file mode 100644 (file)
index 0000000..7799635
--- /dev/null
+++ b/source/backends/opengl/extension.h
@@ -0,0 +1,79 @@
+#ifndef MSP_GL_EXTENSION_H_
+#define MSP_GL_EXTENSION_H_
+
+#include <string>
+#include "backend.h"
+
+namespace Msp {
+namespace GL {
+
+enum GLProfile
+{
+       CORE_PROFILE,
+       COMPATIBILITY_PROFILE
+};
+
+
+/**
+Holds metadata about an extension.  Evaluates to true if the extension is
+supported.
+*/
+class Extension
+{
+public:
+       enum SupportLevel
+       {
+               UNSUPPORTED,
+               EXTENSION,
+               CORE
+       };
+
+       typedef SupportLevel (*InitFunc)();
+
+private:
+       const char *name;
+       InitFunc init_func;
+       mutable bool init_done;
+       mutable SupportLevel support;
+
+public:
+       Extension(const char *, InitFunc);
+
+       const char *get_name() const { return name; }
+       operator bool() const;
+};
+
+
+struct Require
+{
+       Require(const Extension &);
+};
+
+
+typedef void ExtFunc();
+
+/** Checks for extension support.  Only intended for internal use. */
+bool is_supported(const std::string &);
+
+/** Checks for OpenGL version support.  Only intended for internal use. */
+bool is_supported(const Version &, const Version & = Version());
+
+/** Indicates whether an extension has been disabled, either explicitly through
+the MSPGL_DISABLE_EXTENSIONS environment variable or implicitly as a workaround
+for a driver bug.  Only intended for internal use. */
+bool is_disabled(const std::string &);
+
+/** Returns the OpenGL profile for the active context. */
+GLProfile get_gl_profile();
+
+/** Returns the GLSL version number, as reported by the implementation. */
+const Version &get_glsl_version();
+
+/** Returns the address of an extension function.  Only indended for internal
+use. */
+ExtFunc *get_proc_address(const std::string &);
+
+} // namespace GL
+} // namespace Msp
+
+#endif