fix(ui-bug): Fix mission waypoint/stopover/mark pointers disappearing (…

…endless-sky#10841)

source/MapPanel.cpp

@@ -69,15 +69,37 @@ namespace {
 	const unsigned MAX_MISSION_POINTERS_DRAWN = 12;
 	const double MISSION_POINTERS_ANGLE_DELTA = 30.;
 
-	// Struct to track per system how many pointers are drawn and still
+	// Class to track per system how many pointers are drawn and still
 	// need to be drawn.
-	struct PointerDrawCount {
+	class PointerDrawCount {
+	public:
+		// Calculate and check the most number of pointer positions that should be available for active missions.
+		// This can be up to half the maximum number of pointers that can be drawn.
+		void Reserve();
+
+		unsigned MaximumActive() const;
+
+	public:
 		// Amount of systems already drawn.
 		unsigned drawn = 0;
 		unsigned available = 0;
 		unsigned unavailable = 0;
+
+	private:
+		unsigned maximumActive = MAX_MISSION_POINTERS_DRAWN;
 	};
 
+	void PointerDrawCount::Reserve()
+	{
+		maximumActive = max(MAX_MISSION_POINTERS_DRAWN / 2, MAX_MISSION_POINTERS_DRAWN - (available + unavailable));
+	}
+
+	unsigned PointerDrawCount::MaximumActive() const
+	{
+		return maximumActive;
+	}
+
+
 	// Struct for storing the ends of wormhole links and their colors.
 	struct WormholeArrow {
 		WormholeArrow() = default;
@@ -1454,6 +1476,7 @@ void MapPanel::DrawMissions()
 		else
 			++it.unavailable;
 	}
+	for_each(missionCount.begin(), missionCount.end(), [](auto &it) { it.second.Reserve(); });
 	for(const Mission &mission : player.Missions())
 	{
 		if(!mission.IsVisible())
@@ -1463,39 +1486,44 @@ void MapPanel::DrawMissions()
 		if(!system)
 			continue;
 
-		// Reserve a maximum of half of the slots for available missions.
-		auto &&it = missionCount[system];
-		int reserved = min(MAX_MISSION_POINTERS_DRAWN / 2, it.available + it.unavailable);
-		if(it.drawn >= MAX_MISSION_POINTERS_DRAWN - reserved)
-			continue;
-
-		pair<bool, bool> blink = BlinkMissionIndicator(player, mission, step);
-		bool isSatisfied = IsSatisfied(player, mission) && blink.second;
-		DrawPointer(system, it.drawn, blink.first ? black : isSatisfied ? currentColor : blockedColor, isSatisfied);
+		auto &it = missionCount[system];
+		if(it.drawn < it.MaximumActive())
+		{
+			pair<bool, bool> blink = BlinkMissionIndicator(player, mission, step);
+			bool isSatisfied = IsSatisfied(player, mission) && blink.second;
+			const Color &color = blink.first ? black : isSatisfied ? currentColor : blockedColor;
+			DrawPointer(system, it.drawn, it.MaximumActive(), color, isSatisfied);
+		}
 
 		for(const System *waypoint : mission.Waypoints())
-			DrawPointer(waypoint, missionCount[waypoint].drawn, waypointColor);
+			DrawPointer(waypoint, missionCount[waypoint].drawn, missionCount[waypoint].MaximumActive(), waypointColor);
 		for(const Planet *stopover : mission.Stopovers())
-			DrawPointer(stopover->GetSystem(), missionCount[stopover->GetSystem()].drawn, waypointColor);
+		{
+			const System *stopoverSystem = stopover->GetSystem();
+			auto &counts = missionCount[stopoverSystem];
+			DrawPointer(stopoverSystem, counts.drawn, counts.MaximumActive(), waypointColor);
+		}
 		for(const System *mark : mission.MarkedSystems())
-			DrawPointer(mark, missionCount[mark].drawn, waypointColor);
+			DrawPointer(mark, missionCount[mark].drawn, missionCount[mark].MaximumActive(), waypointColor);
 	}
 	// Draw the available and unavailable jobs.
 	for(auto &&it : missionCount)
 	{
 		const auto &system = it.first;
 		auto &&counters = it.second;
 		for(unsigned i = 0; i < counters.available; ++i)
-			DrawPointer(system, counters.drawn, availableColor);
+			DrawPointer(system, counters.drawn, MAX_MISSION_POINTERS_DRAWN, availableColor);
 		for(unsigned i = 0; i < counters.unavailable; ++i)
-			DrawPointer(system, counters.drawn, unavailableColor);
+			DrawPointer(system, counters.drawn, MAX_MISSION_POINTERS_DRAWN, unavailableColor);
 	}
 }
 
 
 
-void MapPanel::DrawPointer(const System *system, unsigned &systemCount, const Color &color, bool bigger)
+void MapPanel::DrawPointer(const System *system, unsigned &systemCount, unsigned max, const Color &color, bool bigger)
 {
+	if(systemCount >= max)
+		return;
 	DrawPointer(Zoom() * (system->Position() + center), systemCount, color, true, bigger);
 }
 

source/MapPanel.h

@@ -176,7 +176,7 @@ class MapPanel : public Panel {
 	void DrawSystems();
 	void DrawNames();
 	void DrawMissions();
-	void DrawPointer(const System *system, unsigned &systemCount, const Color &color, bool bigger = false);
+	void DrawPointer(const System *system, unsigned &systemCount, unsigned max, const Color &color, bool bigger = false);
 	static void DrawPointer(Point position, unsigned &systemCount, const Color &color,
 		bool drawBack = true, bool bigger = false);