--- \dll\iup\a\src\iup_colorhsi.c	2019-07-25 16:27:06.000000000 -0300
+++ iup_colorhsi.c	2020-02-14 14:08:29.349414800 -0300
@@ -40,7 +40,7 @@
 
 static double iColorReconstruct(unsigned char value)
 {
-  if (value <= 0) return 0.0;
+  if (value == 0) return 0.0;
   if (value >= 255) return 1.0;
   return (((double)value + 0.5)/256.0);
 }