add kOfxImageClipPropUniqueIdentifier

Signed-off-by: Greg Cotten <[email protected]>

Author: gregcotten

include/ofxImageEffect.h

@@ -1033,6 +1033,21 @@ The default for a clip descriptor is to have none set, the plugin \em must defin
 */
 #define kOfxImageEffectPropSupportedComponents "OfxImageEffectPropSupportedComponents"
 
+/** @brief Uniquely identifies a clip. 
+
+   - Type - ASCII string X 1
+   - Property Set - clip instance (read only)
+
+This is host set and allows a plug-in to differentiate between clips and respond to those changes. This value should be
+consistent across plugins. This can be useful for seeding a random number generator unique at the clip level. 
+
+The host should change this value when the underlying source for the clip changes or anytime the end user might perceive 
+the clip as being different or new.
+
+The host should make sure that this value is peristent across sessions and that the value is truly unique.
+*/
+#define kOfxImageClipPropUniqueIdentifier "OfxImageClipPropUniqueIdentifier"
+
 /** @brief Indicates if a clip is optional.
 
    - Type - int X 1