Added a new "original" difficulty.

This difficulty is meant to imitate the original Project: Starfighter
as closely as possible, for purists.

src/bullet.cpp

@@ -425,7 +425,7 @@ void doBullets()
 			}
 		}
 
-		if ((currentGame.difficulty > DIFFICULTY_EASY) &&
+		if ((currentGame.difficulty != DIFFICULTY_EASY) &&
 			((bullet->owner == &player) || (bullet->id == WT_ROCKET)))
 		{
 			for (int j = 0 ; j < 20 ; j++)

src/collectable.cpp

@@ -50,8 +50,9 @@ void addCollectable(float x, float y, int type, int value, int life)
 	{
 		type = P_PLASMA_RATE;
 
-		if ((currentGame.difficulty >= DIFFICULTY_NIGHTMARE) ||
+		if ((currentGame.difficulty == DIFFICULTY_NIGHTMARE) ||
-			((currentGame.difficulty > DIFFICULTY_EASY) &&
+			((currentGame.difficulty != DIFFICULTY_EASY) &&
+				(currentGame.difficulty != DIFFICULTY_ORIGINAL) &&
 				((currentGame.area == 5) || (currentGame.area == 11) ||
 					(currentGame.area == 18) || (currentGame.area == 25))))
 		{

src/defs.h

@@ -374,10 +374,12 @@ enum {
 
 // Difficulties
 enum {
-	DIFFICULTY_EASY,
+	DIFFICULTY_EASY = 0,
 	DIFFICULTY_NORMAL,
 	DIFFICULTY_HARD,
-	DIFFICULTY_NIGHTMARE
+	DIFFICULTY_NIGHTMARE,
+	DIFFICULTY_ORIGINAL,
+	DIFFICULTY_MAX
 };
 
 extern const char *systemNames[];

src/game.cpp

@@ -106,6 +106,16 @@ void newGame()
 			player.maxShield = 1;
 			currentGame.maxRocketAmmo = 5;
 			break;
+		case DIFFICULTY_ORIGINAL:
+			player.maxShield = 25;
+
+			currentGame.minPlasmaRateLimit = 3;
+			currentGame.minPlasmaDamageLimit = 3;
+			currentGame.minPlasmaOutputLimit = 3;
+			currentGame.maxPlasmaRateLimit = 5;
+			currentGame.maxPlasmaDamageLimit = 5;
+			currentGame.maxPlasmaOutputLimit = 5;
+			break;
 	}
 
 	player.shield = player.maxShield;

src/intermission.cpp

@@ -527,7 +527,8 @@ int galaxyMap()
 	signed char saveSlot = -1;
 
 	// Remove the Supercharge, if it is there
-	if (currentGame.difficulty > DIFFICULTY_EASY)
+	if ((currentGame.difficulty != DIFFICULTY_EASY) &&
+		(currentGame.difficulty != DIFFICULTY_ORIGINAL))
 	{
 		weapon[W_PLAYER_WEAPON].reload[0] = MAX(
 			weapon[W_PLAYER_WEAPON].reload[0],

src/missions.cpp

@@ -158,6 +158,9 @@ void updateSystemStatus()
 		currentGame.area = 6;
 		strcpy(currentGame.stationedName, "Nerod");
 		initPlanetMissions(currentGame.system);
+
+		if (currentGame.difficulty == DIFFICULTY_ORIGINAL)
+			player.maxShield = 50;
 	}
 	else if (currentGame.area == 11)
 	{
@@ -166,6 +169,9 @@ void updateSystemStatus()
 		currentGame.area = 12;
 		strcpy(currentGame.stationedName, "Odeon");
 		initPlanetMissions(currentGame.system);
+
+		if (currentGame.difficulty == DIFFICULTY_ORIGINAL)
+			player.maxShield = 75;
 	}
 	else if (currentGame.area == 18)
 	{
@@ -174,6 +180,9 @@ void updateSystemStatus()
 		currentGame.area = 19;
 		strcpy(currentGame.stationedName, "Pluto");
 		initPlanetMissions(currentGame.system);
+
+		if (currentGame.difficulty == DIFFICULTY_ORIGINAL)
+			player.maxShield = 100;
 	}
 	else // Update the mission for the planet
 	{

src/player.cpp

@@ -244,7 +244,7 @@ void doPlayer()
 						player.x = screen->w - xViewBorder;
 					}
 				}
-				else
+				else if (currentGame.difficulty != DIFFICULTY_ORIGINAL)
 				{
 					cd = player.x - screen->w / 2;
 					if (cd < 0)
@@ -273,7 +273,7 @@ void doPlayer()
 						player.y = screen->h - yViewBorder;
 					}
 				}
-				else
+				else if (currentGame.difficulty != DIFFICULTY_ORIGINAL)
 				{
 					cd = player.y - screen->h / 2;
 					if (cd < 0)

src/title.cpp

@@ -73,6 +73,8 @@ static void createDifficultyMenu()
 		textSurface(TS_DIFFICULTY, "DIFFICULTY - HARD", -1, 370, FONT_WHITE);
 	else if (currentGame.difficulty == DIFFICULTY_NIGHTMARE)
 		textSurface(TS_DIFFICULTY, "DIFFICULTY - NIGHTMARE!", -1, 370, FONT_WHITE);
+	else if (currentGame.difficulty == DIFFICULTY_ORIGINAL)
+		textSurface(TS_DIFFICULTY, "DIFFICULTY - ORIGINAL", -1, 370, FONT_WHITE);
 	else
 		textSurface(TS_DIFFICULTY, "DIFFICULTY - NORMAL", -1, 370, FONT_WHITE);
 }
@@ -430,8 +432,7 @@ int doTitle()
 						else if (selectedOption == 2)
 						{
 							currentGame.difficulty++;
-							if (currentGame.difficulty > DIFFICULTY_NIGHTMARE)
+							currentGame.difficulty %= DIFFICULTY_MAX;
-								currentGame.difficulty = DIFFICULTY_EASY;
 						}
 						else if (selectedOption == listLength)
 						{