Add Os Bridge into test framework

tests/gfx/include/os-ctx.hpp

@@ -0,0 +1,32 @@
+#pragma once
+
+#include <palladium>
+
+enum class Driver {
+  Unknown = 0,
+  OpenGL2 = 1,
+  OpenGL3 = 2,
+  DirectX9 = 3,
+  Citro3D = 4,
+};
+
+namespace PD {
+class OsCtx {
+ public:
+  OsCtx(Driver d) : pDriver(d) {}
+  virtual ~OsCtx() {}
+
+  virtual void Init() {}
+  virtual void Deinit() {}
+  virtual bool Mainloop() { return false; }
+  virtual void ClearViewPort() {}
+  virtual void SwapBuffers() {}
+  PD::fvec2 SizeTranslate(PD::fvec2 in) {
+    return fvec2(in.x * pViewPort.x, in.y * pViewPort.y);
+  }
+
+ protected:
+  PD::ivec2 pViewPort;
+  const Driver pDriver;
+};
+}  // namespace PD