factorize Value::RangeType calculation and correct error

1 files changed, 9 insertions, 1 deletions

diff --git a/src/value.h b/src/value.h
index 4d8346f..388b721 100644
--- a/src/value.h
+++ b/src/value.h
@@ -4,6 +4,7 @@
 #include <vector>
 #include <string>
 #include <algorithm>
+#include <limits>
 
 // Workaround for https://bugreports.qt-project.org/browse/QTBUG-22829
 #ifndef Q_MOC_RUN
@@ -42,10 +43,17 @@ public:
 
     /// inverse begin/end if begin is upper than end
     void normalize() {
-		if (end < begin) {
+		if ((step>0) && (end < begin)) {
 			std::swap(begin,end);
 		}
 	}
+	/// return number of steps, max int value if step is null
+	int nbsteps() const {
+		if (step<=0) {
+			return std::numeric_limits<int>::max();
+		}
+		return (int)((begin-end)/step);
+	}
 
     double begin;
     double step;