From dda0cda30b58da0c25467b152e6f6e5fda63e8a8 Mon Sep 17 00:00:00 2001
From: Paul Davis <paul@linuxaudiosystems.com>
Date: Wed, 27 Jan 2010 15:40:23 +0000
Subject: [PATCH] better algorithm for checking when AU plugins ::can_do() a
 particular IO configuration (Ben Loftis)

git-svn-id: svn://localhost/ardour2/branches/2.0-ongoing@6574 d708f5d6-7413-0410-9779-e7cbd77b26cf
---
 libs/ardour/audio_unit.cc | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/libs/ardour/audio_unit.cc b/libs/ardour/audio_unit.cc
index 610e54a6ff..7e472eb90e 100644
--- a/libs/ardour/audio_unit.cc
+++ b/libs/ardour/audio_unit.cc
@@ -801,6 +801,18 @@ AUPlugin::can_do (int32_t in, int32_t& out)
 		cerr << name() << " has " << io_configs.size() << " IO Configurations\n";
 	}
 
+	//first search for the simple case that matches what we need exactly
+	for (vector<pair<int,int> >::iterator i = io_configs.begin(); i != io_configs.end(); ++i) {
+		int32_t possible_in = i->first;
+		int32_t possible_out = i->second;
+
+		if (possible_in == in && possible_out== out) {
+			return 1;
+		}
+	}
+
+	/* now allow potentially "imprecise" matches */
+
 	for (vector<pair<int,int> >::iterator i = io_configs.begin(); i != io_configs.end(); ++i) {
 
 		int32_t possible_in = i->first;