CarpetLib: Generalise "expand" function. Implement "shift" function.

Allow expanding bboxset by multiples of a fraction of the stride.
Allow shifting bboxsets.

1 files changed, 24 insertions, 1 deletions

diff --git a/Carpet/CarpetLib/src/bboxset.cc b/Carpet/CarpetLib/src/bboxset.cc
index 7ffd61699..a830c0b73 100644
--- a/Carpet/CarpetLib/src/bboxset.cc
+++ b/Carpet/CarpetLib/src/bboxset.cc
@@ -464,7 +464,9 @@ bboxset<T,D> bboxset<T,D>::pseudo_inverse (const int n) const {
 }
 
 template<typename T, int D>
-bboxset<T,D> bboxset<T,D>::expand (const vect<T,D>& lo, const vect<T,D>& hi) const {
+bboxset<T,D> bboxset<T,D>::expand (const vect<T,D>& lo, const vect<T,D>& hi)
+  const
+{
   // We don't know (yet?) how to shrink a set
   assert (all (lo>=0 and hi>=0));
   bboxset res;
@@ -475,6 +477,27 @@ bboxset<T,D> bboxset<T,D>::expand (const vect<T,D>& lo, const vect<T,D>& hi) con
 }
 
 template<typename T, int D>
+bboxset<T,D> bboxset<T,D>::expand (const vect<T,D>& lo, const vect<T,D>& hi,
+                                   const vect<T,D>& denom) const
+{
+  assert (all(denom > vect<T,D>(0)));
+  bboxset res;
+  if (all (lo == -hi)) {
+    // Special case for shifting, since this is faster
+    for (const_iterator bi=begin(); bi!=end(); ++bi) {
+      res += (*bi).expand(lo,hi,denom);
+    }
+  } else {
+    // We don't know (yet?) how to shrink a set
+    assert (all ((lo>=0 and hi>=0) or (lo == hi)));
+    for (const_iterator bi=begin(); bi!=end(); ++bi) {
+      res |= (*bi).expand(lo,hi,denom);
+    }
+  }
+  return res;
+}
+
+template<typename T, int D>
 bboxset<T,D> bboxset<T,D>::expanded_for (const box& b) const {
   bboxset res;
   for (const_iterator bi=begin(); bi!=end(); ++bi) {