Implement BotPredictVisiblePosition and export wiring

src/botlib/ai_move/bot_move.c

@@ -519,6 +519,31 @@ static float VectorNormalizeTo(const vec3_t src, vec3_t dst)
     return VectorNormalizeInline(dst);
 }
 
+/*
+=============
+BotMove_VisiblePosition
+
+Checks if a point is visible from a viewpoint.
+=============
+*/
+static bool BotMove_VisiblePosition(int ent, const vec3_t eye, const vec3_t target)
+{
+	if (eye == NULL || target == NULL)
+	{
+		return false;
+	}
+
+	vec3_t start;
+	vec3_t end;
+	VectorCopy(eye, start);
+	VectorCopy(target, end);
+
+	vec3_t mins = {0.0f, 0.0f, 0.0f};
+	vec3_t maxs = {0.0f, 0.0f, 0.0f};
+	bsp_trace_t trace = Q2_Trace(start, mins, maxs, end, ent, CONTENTS_SOLID | CONTENTS_PLAYERCLIP);
+	return trace.fraction >= 1.0f;
+}
+
 static int BotMove_FindAreaForPoint(const vec3_t origin)
 {
     if (!aasworld.loaded || aasworld.areas == NULL || aasworld.numAreas <= 0)
@@ -1511,3 +1536,59 @@ void BotMove_ResetAvoidReach(int movestate)
     memset(ms->avoidreachtries, 0, sizeof(ms->avoidreachtries));
 }
 
+/*
+=============
+BotPredictVisiblePosition
+
+Predicts a reachability point that remains visible from the goal.
+=============
+*/
+int BotPredictVisiblePosition(vec3_t origin, int areanum, bot_goal_t *goal, int travelflags, vec3_t target)
+{
+	if (goal == NULL || target == NULL)
+	{
+		return false;
+	}
+
+	if (!areanum || !goal->areanum)
+	{
+		return false;
+	}
+
+	bot_movestate_t temp_state;
+	memset(&temp_state, 0, sizeof(temp_state));
+
+	for (int i = 0; i < 20 && areanum != goal->areanum; ++i)
+	{
+		aas_reachability_t reach;
+		temp_state.areanum = areanum;
+
+		int reachnum = BotGetReachabilityToGoal(&temp_state, goal, travelflags, &reach, NULL);
+		if (!reachnum)
+		{
+			return false;
+		}
+
+		if (BotMove_VisiblePosition(goal->entitynum, goal->origin, reach.start))
+		{
+			VectorCopy(reach.start, target);
+			return true;
+		}
+
+		if (BotMove_VisiblePosition(goal->entitynum, goal->origin, reach.end))
+		{
+			VectorCopy(reach.end, target);
+			return true;
+		}
+
+		if (reach.areanum == goal->areanum)
+		{
+			VectorCopy(reach.end, target);
+			return true;
+		}
+
+		areanum = reach.areanum;
+	}
+
+	return false;
+}

src/botlib/ai_move/bot_move.h

@@ -166,6 +166,8 @@ int BotMoveInDirection(int movestate, const vec3_t dir, float speed, int type);
 
 void BotMove_ResetAvoidReach(int movestate);
 
+int BotPredictVisiblePosition(vec3_t origin, int areanum, bot_goal_t *goal, int travelflags, vec3_t target);
+
 void AI_MoveFrame(bot_moveresult_t *result,
                   int movestate,
                   const bot_goal_t *goal,
@@ -176,4 +178,3 @@ bot_moveresult_t BotTravel_Grapple(bot_movestate_t *ms, const struct aas_reachab
 #ifdef __cplusplus
 } /* extern "C" */
 #endif
-

src/botlib/interface/bot_interface.c

@@ -3170,6 +3170,27 @@ static void BotInterface_BotResetAvoidReach(int movestate)
     BotMove_ResetAvoidReach(movestate);
 }
 
+/*
+=============
+BotInterface_BotPredictVisiblePosition
+
+Routes the visibility prediction request to the bot movement module.
+=============
+*/
+static int BotInterface_BotPredictVisiblePosition(vec3_t origin,
+												  int areanum,
+												  bot_goal_t *goal,
+												  int travelflags,
+												  vec3_t target)
+{
+	if (!BotInterface_EnsureLibraryReady("BotPredictVisiblePosition"))
+	{
+		return 0;
+	}
+
+	return BotPredictVisiblePosition(origin, areanum, goal, travelflags, target);
+}
+
 static int BotInterface_BotAllocWeaponState(void)
 {
     if (!BotInterface_EnsureLibraryReady("BotAllocWeaponState"))
@@ -3454,6 +3475,7 @@ GLADIATOR_API bot_export_t *GetBotAPI(bot_import_t *import)
     exportTable.BotMoveToGoal = BotInterface_BotMoveToGoal;
     exportTable.BotMoveInDirection = BotInterface_BotMoveInDirection;
     exportTable.BotResetAvoidReach = BotInterface_BotResetAvoidReach;
+    exportTable.BotPredictVisiblePosition = BotInterface_BotPredictVisiblePosition;
     exportTable.BotLoadCharacter = BotLoadCharacter;
     exportTable.BotFreeCharacter = BotFreeCharacter;
     exportTable.BotLoadCharacterSkill = BotLoadCharacterSkill;
@@ -3485,4 +3507,3 @@ GLADIATOR_API bot_export_t *GetBotAPI(bot_import_t *import)
 
     return &exportTable;
 }
-

src/q2bridge/botlib.h

@@ -262,6 +262,7 @@ typedef struct bot_export_s {
     void (*BotMoveToGoal)(bot_moveresult_t *result, int movestate, const bot_goal_t *goal, int travelflags);
     int (*BotMoveInDirection)(int movestate, const vec3_t dir, float speed, int type);
     void (*BotResetAvoidReach)(int movestate);
+	int (*BotPredictVisiblePosition)(vec3_t origin, int areanum, bot_goal_t *goal, int travelflags, vec3_t target);
     int (*BotLoadCharacter)(const char *character_file, float skill);
     void (*BotFreeCharacter)(int handle);
     int (*BotLoadCharacterSkill)(const char *character_file, float skill);