Add EGL_NV_n_buffer extensions.
diff --git a/api/EGL/eglext.h b/api/EGL/eglext.h
index b1b9421..16e78ea 100644
--- a/api/EGL/eglext.h
+++ b/api/EGL/eglext.h
@@ -1108,6 +1108,12 @@
 #define EGL_CUDA_DEVICE_NV                0x323A
 #endif /* EGL_NV_device_cuda */
 
+#ifndef EGL_NV_n_buffer
+#define EGL_NV_n_buffer 1
+#define EGL_TRIPLE_BUFFER_NV              0x3230
+#define EGL_QUADRUPLE_BUFFER_NV           0x3231
+#endif /* EGL_NV_n_buffer */
+
 #ifndef EGL_NV_native_query
 #define EGL_NV_native_query 1
 typedef EGLBoolean (EGLAPIENTRYP PFNEGLQUERYNATIVEDISPLAYNVPROC) (EGLDisplay dpy, EGLNativeDisplayType *display_id);
diff --git a/api/egl.xml b/api/egl.xml
index 01b6c25..cb61c47 100644
--- a/api/egl.xml
+++ b/api/egl.xml
@@ -2926,6 +2926,12 @@
                 <enum name="EGL_CUDA_DEVICE_NV"/>
             </require>
         </extension>
+        <extension name="EGL_NV_n_buffer" supported="egl">
+            <require>
+                <enum name="EGL_TRIPLE_BUFFER_NV"/>
+                <enum name="EGL_QUADRUPLE_BUFFER_NV"/>
+            </require>
+        </extension>
         <extension name="EGL_NV_native_query" supported="egl">
             <require>
                 <command name="eglQueryNativeDisplayNV"/>