Fix glitch in drawing fractions

[lyx.git] / src / Cursor.cpp

diff --git a/src/Cursor.cpp b/src/Cursor.cpp
index e2d1f893ae120d986073905fe3ef217c38b02192..822dc6e53cbb1519357479fe8224a393502e93c1 100644 (file)
--- a/src/Cursor.cpp
+++ b/src/Cursor.cpp
@@ -1742,6 +1742,77 @@ bool Cursor::upDownInMath(bool up)
 }
 
 
+InsetMath & Cursor::nextMath()
+{
+       return *nextAtom().nucleus();
+}
+
+
+InsetMath & Cursor::prevMath()
+{
+       return *prevAtom().nucleus();
+}
+
+
+bool Cursor::mathForward(bool word)
+{
+       LASSERT(inMathed(), return false);
+       if (pos() < lastpos()) {
+               if (word) {
+                       // word: skip a group of insets with same math class
+                       MathClass mc = nextMath().mathClass();
+                       do
+                               posForward();
+                       while (pos() < lastpos() && mc == nextMath().mathClass());
+               } else if (openable(nextAtom())) {
+                       // single step: try to enter the next inset
+                       pushBackward(nextMath());
+                       inset().idxFirst(*this);
+               } else
+                       posForward();
+               return true;
+       }
+       if (inset().idxForward(*this))
+               return true;
+       // try to pop forwards --- but don't pop out of math! leave that to
+       // the FINISH lfuns
+       int s = depth() - 2;
+       if (s >= 0 && operator[](s).inset().asInsetMath())
+               return popForward();
+       return false;
+}
+
+
+bool Cursor::mathBackward(bool word)
+{
+       LASSERT(inMathed(), return false);
+       if (pos() > 0) {
+               if (word) {
+                       // word: skip a group of insets with same math class
+                       MathClass mc = prevMath().mathClass();
+                       do
+                               posBackward();
+                       while (pos() > 0 && mc == prevMath().mathClass());
+               } else if (openable(prevAtom())) {
+                       // single step: try to enter the preceding inset
+                       posBackward();
+                       push(nextMath());
+                       inset().idxLast(*this);
+               } else
+                       posBackward();
+               return true;
+       }
+       if (inset().idxBackward(*this))
+               return true;
+       // try to pop backwards --- but don't pop out of math! leave that to
+       // the FINISH lfuns
+       int s = depth() - 2;
+       if (s >= 0 && operator[](s).inset().asInsetMath())
+               return popBackward();
+       return false;
+}
+
+
 bool Cursor::atFirstOrLastRow(bool up)
 {
        TextMetrics const & tm = bv_->textMetrics(text());