From f90965211fc349d8f7fbf1beedbf6964fc8f599a Mon Sep 17 00:00:00 2001
From: andy <andy>
Date: Thu, 8 Dec 2011 12:48:21 +0000
Subject: [PATCH] ENH: AMI - use pre-calculated areas instead of re-calculation

---
 .../AMIInterpolation/AMIInterpolation.C           | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/src/meshTools/AMIInterpolation/AMIInterpolation/AMIInterpolation.C b/src/meshTools/AMIInterpolation/AMIInterpolation/AMIInterpolation.C
index 74c0235606..a9c9113056 100644
--- a/src/meshTools/AMIInterpolation/AMIInterpolation/AMIInterpolation.C
+++ b/src/meshTools/AMIInterpolation/AMIInterpolation/AMIInterpolation.C
@@ -889,21 +889,22 @@ Foam::scalar Foam::AMIInterpolation<SourcePatch, TargetPatch>::interArea
     const primitivePatch& tgtPatch
 ) const
 {
-    const pointField& srcPoints = srcPatch.points();
-    const pointField& tgtPoints = tgtPatch.points();
-
-    const face& src = srcPatch[srcFaceI];
-    const face& tgt = tgtPatch[tgtFaceI];
-
     // quick reject if either face has zero area
-    if ((src.mag(srcPoints) < ROOTVSMALL) || (tgt.mag(tgtPoints) < ROOTVSMALL))
+    if (srcMagSf_[srcFaceI] < ROOTVSMALL || tgtMagSf_[tgtFaceI] < ROOTVSMALL)
     {
         return 0.0;
     }
 
+    const pointField& srcPoints = srcPatch.points();
+    const pointField& tgtPoints = tgtPatch.points();
+
     // create intersection object
     faceAreaIntersect inter(srcPoints, tgtPoints, reverseTarget_);
 
+    // references to candidate faces
+    const face& src = srcPatch[srcFaceI];
+    const face& tgt = tgtPatch[tgtFaceI];
+
     // crude resultant norm
     vector n(-src.normal(srcPoints));
     if (reverseTarget_)