take into account lvl up heal when estimating attack prediction,

...patch by roger_wilco

data/core/about.cfg

@@ -39,6 +39,9 @@
         wikiuser = "bruno"
         email = "bruno_AT_wolff.to"
     [/entry]
+    [entry]
+        name = "Cameron Morland"
+    [/entry]
     [entry]
         name = "Cédric Duval"
         comment = "coder, internationalization manager"

src/actions.cpp

@@ -625,6 +625,11 @@ battle_context::unit_stats::unit_stats(const unit &u, const gamemap::location& u
 		dloc = &u_loc;
 	}
 
+	// these can matter, even if we can't hit back!
+	experience = u.experience();
+	max_experience = u.max_experience();
+	level = u.level();
+
 	// Get the weapon characteristics, if any.
 	if (weapon) {
 		weapon->set_specials_context(*aloc, *dloc, &units, &map, &status, &teams, attacking, opp_weapon);

src/actions.hpp

@@ -88,6 +88,8 @@ public:
 								 */
 		bool swarm;				/**< Attack has swarm special. */
 		bool firststrike;		/**< Attack has firststrike special. */
+		unsigned int experience, max_experience;
+		unsigned int level;
 
 		unsigned int rounds;	/**< Berserk special can force us to fight more than one round. */
 		unsigned int hp;		/**< Hitpoints of the unit at the beginning of the battle. */

src/attack_prediction.cpp

@@ -494,10 +494,8 @@ unsigned combatant::hp_dist_size(const battle_context::unit_stats &u, const comb
 	}
 
 	// If this unit drains, HP can increase, so alloc full array.
-	if (u.drains) {
-		return u.max_hp + 1;
-	}
-	return u.hp+1;
+	// Do this anyway in case we level up.
+	return u.max_hp + 1;
 }
 
 combatant::combatant(const battle_context::unit_stats &u, const combatant *prev)
@@ -587,7 +585,7 @@ void combatant::no_death_fight(combatant &opp)
 {
 	if (summary[0].empty()) {
 		// Starts with a known HP, so Pascal's triangle.
-		summary[0] = std::vector<double>(u_.hp+1);
+		summary[0] = std::vector<double>(u_.max_hp+1);
 		summary[0][u_.hp] = 1.0;
 		for (unsigned int i = 0; i < opp.hit_chances_.size(); i++) {
 			for (int j = i; j >= 0; j--) {
@@ -609,7 +607,7 @@ void combatant::no_death_fight(combatant &opp)
 
 	if (opp.summary[0].empty()) {
 		// Starts with a known HP, so Pascal's triangle.
-		opp.summary[0] = std::vector<double>(opp.u_.hp+1);
+		opp.summary[0] = std::vector<double>(opp.u_.max_hp+1);
 		opp.summary[0][opp.u_.hp] = 1.0;
 		for (unsigned int i = 0; i < hit_chances_.size(); i++) {
 			for (int j = i; j >= 0; j--) {
@@ -634,7 +632,7 @@ void combatant::no_death_fight(combatant &opp)
 void combatant::one_strike_fight(combatant &opp)
 {
 	if (opp.summary[0].empty()) {
-		opp.summary[0] = std::vector<double>(opp.u_.hp+1);
+		opp.summary[0] = std::vector<double>(opp.u_.max_hp+1);
 		if (hit_chances_.size() == 1) {
 			opp.summary[0][opp.u_.hp] = 1.0 - hit_chances_[0];
 			opp.summary[0][maximum<int>(opp.u_.hp - u_.damage, 0)] = hit_chances_[0];
@@ -655,7 +653,7 @@ void combatant::one_strike_fight(combatant &opp)
 	// If we killed opponent, it won't attack us.
 	double opp_alive_prob = 1.0 - opp.summary[0][0];
 	if (summary[0].empty()) {
-		summary[0] = std::vector<double>(u_.hp+1);
+		summary[0] = std::vector<double>(u_.max_hp+1);
 		if (opp.hit_chances_.size() == 1) {
 			summary[0][u_.hp] = 1.0 - opp.hit_chances_[0] * opp_alive_prob;
 			summary[0][maximum<int>(u_.hp - opp.u_.damage, 0)] = opp.hit_chances_[0] * opp_alive_prob;
@@ -723,6 +721,48 @@ void combatant::complex_fight(combatant &opp, unsigned int rounds)
 	m.extract_results(summary, opp.summary);
 }
 
+void combatant::consider_levelup(combatant &opp) {
+	// adjust the probabilities to take into consideration the
+	// probability of us levelling up, and hence healing.
+	// We do not currently estimate how many HP we will have.
+
+	if (u_.experience + opp.u_.level >= u_.max_experience) {
+		// if we survive the combat, we will level up. So the probability
+		// of death is unchanged, but all other cases get merged into
+		// the fully healed case.
+		std::vector<double>::iterator i;
+		i = hp_dist.begin();
+		i++; // skip to the second value
+		for ( ; i != hp_dist.end(); i++) {
+			*i = 0;
+		}
+		// fully healed unless dead
+		hp_dist.back() = 1 - hp_dist.front();
+		
+		
+
+	} else if (u_.experience + ((opp.u_.level == 0) ? 4 : opp.u_.level * 8) 
+						 >= u_.max_experience) {
+		// if we kill, we will level up. So then the damage we had
+		// becomes less probable since it's now conditional on us not
+		// levelling up.  This doesn't apply to the probability of us
+		// dying, of course.
+		float scalefactor = 
+			(1 - hp_dist.front() - opp.hp_dist.front()) / (1 - hp_dist.front());
+		std::vector<double>::iterator i;
+		i = hp_dist.begin();
+		i++; // skip to the second value
+		for( ; i != hp_dist.end(); i++) {
+			*i *= scalefactor;
+		}
+
+		// if we level up, we get fully healed. (FIXME: actually more so; we
+		// need to calculate how many HP we will gain)
+		hp_dist.back() += opp.hp_dist.front();
+	}
+
+}
+
 // Two man enter.  One man leave!
 // ... Or maybe two.  But definitely not three.
 // Of course, one could be a woman.  Or both.
@@ -804,6 +844,9 @@ void combatant::fight(combatant &opp)
 			opp.hp_dist[i] = opp.summary[0][i] + opp.summary[1][i];
 	}
 
+	consider_levelup(opp);
+	opp.consider_levelup(*this);
+
 	// Make sure we don't try to access the vectors out of bounds,
 	// drain increases HPs so we determine the number of HP here
 	// and make sure it stays within bounds

src/attack_prediction.hpp

@@ -35,6 +35,9 @@ struct combatant
 	/** Simulate a fight!  Can be called multiple times for cumulative calculations. */
 	void fight(combatant &opponent);
 
+	/** takes into account level up when calculating resulting HP after a fight */
+	void consider_levelup(combatant &opponent);
+
 	/** Resulting probability distribution (may NOT be as large as max_hp) */
 	std::vector<double> hp_dist;