X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Fbindable.h;h=bde5e85a11752b3a95a07de5187ad174b3c4a50a;hb=706d49dc7ca9b3969f6f79db16b0cc02576f3de3;hp=8823de5c9773209a1642f5b763887e65ca7ea5d6;hpb=f14435e58bfa0fa697a06ba9a454bb30cd37d9d8;p=libs%2Fgl.git

diff --git a/source/bindable.h b/source/bindable.h
index 8823de5c..bde5e85a 100644
--- a/source/bindable.h
+++ b/source/bindable.h
@@ -4,6 +4,10 @@
 namespace Msp {
 namespace GL {
 
+/**
+A helper class for single-point binding.  Provides tracking of the currently
+bound object.
+*/
 template<typename T>
 class Bindable
 {
@@ -29,6 +33,36 @@ template<typename T>
 const T *Bindable<T>::cur_obj;
 
 
+/**
+A helper class for Bindables that revert to a default object on unbind.
+*/
+template<typename T>
+class BindableWithDefault: protected Bindable<T>
+{
+protected:
+	BindableWithDefault() { }
+
+public:
+	static const T *current()
+	{
+		if(!Bindable<T>::cur_obj)
+			Bindable<T>::cur_obj = &default_object();
+		return Bindable<T>::cur_obj;
+	}
+
+	static void unbind()
+	{
+		default_object().bind();
+	}
+
+	static const T &default_object()
+	{
+		static T obj;
+		return obj;
+	}
+};
+
+
 /**
 RAII class for binding things.  Binds the thing upon construction and unbinds
 it upon destruction.  If a null pointer is given, unbinds upon construction and