diff --git a/apps/shared/range_1D.h b/apps/shared/range_1D.h
index a528540f0..1557e82b6 100644
--- a/apps/shared/range_1D.h
+++ b/apps/shared/range_1D.h
@@ -16,6 +16,8 @@ namespace Shared {
 
 class __attribute__((packed)) Range1D final {
 public:
+  /* If m_min and m_max are too close, we cannot divide properly the range by
+   * the number of pixels, which creates a drawing problem. */
   constexpr static float k_minFloat = 1E-4f;
   constexpr static float k_default = 10.0f;
   Range1D(float min = -k_default, float max = k_default) :