Reenable fog toggle unless server restricts fog distance (#14634)

see comments in #14539

builtin/settingtypes.txt

@@ -381,8 +381,7 @@ crosshair_alpha (Crosshair alpha) int 255 0 255
 
 [**Fog]
 
-#    Whether to fog out the end of the visible area. This option only works
-#    with the 'debug' privilege.
+#    Whether to fog out the end of the visible area.
 enable_fog (Fog) bool true
 
 #    Make fog and sky colors depend on daytime (dawn/sunset) and view direction.
@@ -2511,7 +2510,7 @@ keymap_toggle_chat (Chat toggle key) key KEY_F2
 #    Key for toggling the display of the large chat console.
 keymap_console (Large chat console key) key KEY_F10
 
-#    Key for toggling the display of fog. Only usable with 'debug' privilege.
+#    Key for toggling the display of fog.
 keymap_toggle_fog (Fog toggle key) key KEY_F3
 
 #    Key for toggling the camera update. Only usable with 'debug' privilege.

doc/lua_api.md

@@ -8257,14 +8257,13 @@ child will follow movement and rotation of that bone.
                 `"default"` uses the classic Minetest sun and moon tinting.
                 Will use tonemaps, if set to `"default"`. (default: `"default"`)
         * `fog`: A table with following optional fields:
-            * `fog_distance`: integer, set an upper bound the client's viewing_range (inluding range_all).
-               By default, fog_distance is controlled by the client's viewing_range, and this field is not set.
-               Any value >= 0 sets the desired upper bound for the client's viewing_range and disables range_all.
-               Any value < 0, resets the behavior to being client-controlled.
+            * `fog_distance`: integer, set an upper bound for the client's viewing_range.
+               Any value >= 0 sets the desired upper bound for viewing_range,
+               disables range_all and prevents disabling fog (F3 key by default).
+               Any value < 0 resets the behavior to being client-controlled.
                (default: -1)
             * `fog_start`: float, override the client's fog_start.
                Fraction of the visible distance at which fog starts to be rendered.
-               By default, fog_start is controlled by the client's `fog_start` setting, and this field is not set.
                Any value between [0.0, 0.99] set the fog_start as a fraction of the viewing_range.
                Any value < 0, resets the behavior to being client-controlled.
                (default: -1)

src/client/game.cpp

@@ -792,6 +792,14 @@ protected:
 	void showOverlayMessage(const char *msg, float dtime, int percent,
 			bool draw_clouds = true);
 
+	inline bool fogEnabled()
+	{
+		// Client setting only takes effect if fog distance unlimited or debug priv
+		if (sky->getFogDistance() < 0 || client->checkPrivilege("debug"))
+			return m_cache_enable_fog;
+		return true;
+	}
+
 	static void settingChangedCallback(const std::string &setting_name, void *data);
 	void readSettings();
 
@@ -2467,15 +2475,12 @@ void Game::toggleMinimap(bool shift_pressed)
 
 void Game::toggleFog()
 {
-	bool flag;
-	// do not modify setting if no privilege
-	if (!client->checkPrivilege("debug")) {
-		flag = true;
-	} else {
-		flag = !g_settings->getBool("enable_fog");
-		g_settings->setBool("enable_fog", flag);
-	}
-	if (flag)
+	bool flag = !g_settings->getBool("enable_fog");
+	g_settings->setBool("enable_fog", flag);
+	bool allowed = sky->getFogDistance() < 0 || client->checkPrivilege("debug");
+	if (!allowed)
+		m_game_ui->showTranslatedStatusText("Fog enabled by game or mod");
+	else if (flag)
 		m_game_ui->showTranslatedStatusText("Fog enabled");
 	else
 		m_game_ui->showTranslatedStatusText("Fog disabled");
@@ -4230,8 +4235,7 @@ void Game::updateClouds(float dtime)
 		camera_node_position.Y   = camera_node_position.Y + camera_offset.Y * BS;
 		camera_node_position.Z   = camera_node_position.Z + camera_offset.Z * BS;
 		this->clouds->update(camera_node_position, this->sky->getCloudColor());
-		bool enable_fog = this->m_cache_enable_fog || !client->checkPrivilege("debug");
-		if (this->clouds->isCameraInsideCloud() && enable_fog) {
+		if (this->clouds->isCameraInsideCloud() && this->fogEnabled()) {
 			// If camera is inside cloud and fog is enabled, use cloud's colors as sky colors.
 			video::SColor clouds_dark = this->clouds->getColor().getInterpolated(
 					video::SColor(255, 0, 0, 0), 0.9);
@@ -4291,7 +4295,7 @@ void Game::drawScene(ProfilerGraph *graph, RunStats *stats)
 	/*
 		Fog
 	*/
-	if (this->m_cache_enable_fog || !client->checkPrivilege("debug")) {
+	if (this->fogEnabled()) {
 		this->driver->setFog(
 				fog_color,
 				video::EFT_FOG_LINEAR,

src/defaultsettings.cpp

@@ -172,11 +172,10 @@ void set_default_settings()
 	settings->setDefault("keymap_toggle_block_bounds", "");
 	settings->setDefault("keymap_toggle_hud", "KEY_F1");
 	settings->setDefault("keymap_toggle_chat", "KEY_F2");
-#ifndef NDEBUG
 	settings->setDefault("keymap_toggle_fog", "KEY_F3");
+#ifndef NDEBUG
 	settings->setDefault("keymap_toggle_update_camera", "KEY_F4");
 #else
-	settings->setDefault("keymap_toggle_fog", "");
 	settings->setDefault("keymap_toggle_update_camera", "");
 #endif
 	settings->setDefault("keymap_toggle_debug", "KEY_F5");