Clamp tod_color values in the [-510, 510] range instead of [-255, 255]

[color_adjust] needs to be able to use absolute values as large as
2*255 in certain edge cases to set the screen a single solid colour when
interacting with time of day colour shifts.

Fixes #3144.

changelog.md

@@ -25,6 +25,8 @@
    * Experimental AI: fixed recruiting evaluations sometimes not being updated
    * Replaced deprecated Lua code and all remaining uses of FOREACH and MESSAGE
      macros
+   * Fixed [color_adjust] interacting poorly with time of day color shifts and
+     values outside the [-255, 255] range (issue #3144).
 
 ## Version 1.14.1
  ### Campaigns

src/time_of_day.hpp

@@ -27,9 +27,9 @@ class config;
 // This is a color delta, so do not replace with color_t!
 struct tod_color {
 	explicit tod_color(int red = 0, int green = 0, int blue = 0)
-		: r(utils::clamp(red, -255, 255))
-		, g(utils::clamp(green, -255, 255))
-		, b(utils::clamp(blue, -255, 255))
+		: r(utils::clamp(red, -510, 510))
+		, g(utils::clamp(green, -510, 510))
+		, b(utils::clamp(blue, -510, 510))
 	{}
 	bool operator==(const tod_color& o) const {
 		return r == o.r && g == o.g && b == o.b;