ColorScale: safer handling of corner cases.

1 files changed, 12 insertions, 0 deletions

diff --git a/colorscale.cpp b/colorscale.cpp
index f41e7d9..f5afcbb 100644
--- a/colorscale.cpp
+++ b/colorscale.cpp
@@ -1,5 +1,9 @@
 #include "colorscale.h"
 
+#include <cmath>
+
+const float EPSILON = 1e-3f;
+
 ColorScale::ColorScale(const QColor &firstColor, const QColor &lastColor)
     : m_colors{{firstColor, lastColor}}
 {
@@ -62,6 +66,14 @@ QColor ColorScale::color(float t) const
         return lerp(m_colors.first(), m_colors.last(), t);
     }
 
+    if (fabs(t - m_min) < EPSILON) {
+        return m_colors.first();
+    }
+
+    if (fabs(t - m_max) < EPSILON) {
+        return m_colors.last();
+    }
+
     // find which colors in the scale are adjacent to ours
     int i = int(t * m_colors.size());
     int j = i + 1;