Merge pull request #7007 from s-hadinger/fade_new

Change new Fade system much smoother, Speed now up to 40

tasmota/CHANGELOG.md

@@ -3,6 +3,7 @@
 ### 7.0.0.6 20191122
 
 - Add colorpicker to WebUI by Christian Staars (#6984)
+- Change new Fade system much smoother, Speed now up to 40 (#6942, #3714)
 
 ### 7.0.0.5 20191118
 

tasmota/support_float.ino

@@ -375,18 +375,23 @@ float sqrt1(const float x)
 // changeUIntScale
 // Change a value for range a..b to c..d, using only unsigned int math
 //
+// New version, you don't need the "to_min < to_max" precondition anymore
+//
 // PRE-CONDITIONS (if not satisfied, you may 'halt and catch fire')
 //    from_min < from_max  (not checked)
-//    to_min   < to_max    (not checked)
 //    from_min <= num <= from-max  (chacked)
 // POST-CONDITIONS
 //    to_min <= result <= to_max
 //
 uint16_t changeUIntScale(uint16_t inum, uint16_t ifrom_min, uint16_t ifrom_max,
                                        uint16_t ito_min, uint16_t ito_max) {
   // guard-rails
-  if ((ito_min >= ito_max) || (ifrom_min >= ifrom_max)) {
-    return ito_min;  // invalid input, return arbitrary value
+  if (ifrom_min >= ifrom_max) {
+    if (ito_min > ito_max) {
+      return ito_max;
+    } else {
+      return ito_min;  // invalid input, return arbitrary value
+    }
   }
   // convert to uint31, it's more verbose but code is more compact
   uint32_t num = inum;
@@ -397,6 +402,15 @@ uint16_t changeUIntScale(uint16_t inum, uint16_t ifrom_min, uint16_t ifrom_max,
 
   // check source range
   num = (num > from_max ? from_max : (num < from_min ? from_min : num));
+
+  // check to_* order
+  if (to_min > to_max) {
+    // reverse order
+    num = (from_max - num) + from_min;
+    to_min = ito_max;
+    to_max = ito_min;
+  }
+
   uint32_t numerator = (num - from_min) * (to_max - to_min);
   uint32_t result;
   if (numerator >= 0x80000000L) {