moved RNG to common/util.cpp

svn-id: r5778

9 files changed, 52 insertions, 32 deletions

diff --git a/common/util.cpp b/common/util.cpp
index cea9d3a8f0..2423cd0af0 100644
--- a/common/util.cpp
+++ b/common/util.cpp
@@ -157,3 +157,27 @@ int resStrLen(const char *src)
 	}
 	return num;
 }
+
+RandomSource::RandomSource(uint32 seed)
+{
+	_randSeed = seed;
+}
+
+void RandomSource::setSeed(uint32 seed)
+{
+	_randSeed = seed;
+}
+
+uint RandomSource::getRandomNumber(uint max)
+{
+	/* TODO: my own random number generator */
+	_randSeed = 0xDEADBF03 * (_randSeed + 1);
+	_randSeed = (_randSeed >> 13) | (_randSeed << 19);
+	return _randSeed % (max + 1);
+}
+
+uint RandomSource::getRandomNumberRng(uint min, uint max)
+{
+	return getRandomNumber(max - min) + min;
+}
+
diff --git a/common/util.h b/common/util.h
index 37576bd8af..a5e13c0e4f 100644
--- a/common/util.h
+++ b/common/util.h
@@ -72,4 +72,16 @@ void hexdump(const byte * data, int len);
 // Resource string length
 int resStrLen(const char *src);
 
+
+class RandomSource {
+private:
+	uint32 _randSeed;
+
+public:
+	RandomSource(uint32 seed = 0xA943DE33);
+	void setSeed(uint32 seed);
+	uint getRandomNumber(uint max);
+	uint getRandomNumberRng(uint min, uint max);
+};
+
 #endif
diff --git a/scumm/akos.cpp b/scumm/akos.cpp
index cc588cc1b2..10ec09534a 100644
--- a/scumm/akos.cpp
+++ b/scumm/akos.cpp
@@ -1419,7 +1419,7 @@ bool Scumm::akos_increaseAnim(Actor *a, int chan, byte *aksq, uint16 *akfo, int
 			continue;
 
 		case AKC_Random:
-			a->setAnimVar(GB(6), getRandomNumberRng(GW(2), GW(4)));
+			a->setAnimVar(GB(6), _rnd.getRandomNumberRng(GW(2), GW(4)));
 			continue;
 		case AKC_SkipGE:
 		case AKC_SkipG:
diff --git a/scumm/gfx.cpp b/scumm/gfx.cpp
index 9ac04e68cd..21f9211855 100644
--- a/scumm/gfx.cpp
+++ b/scumm/gfx.cpp
@@ -2076,7 +2076,7 @@ void Scumm::dissolveEffect(int width, int height) {
 		for (i = 1; i < w * h; i++) {
 			int j;
 
-			j = getRandomNumber(i - 1);
+			j = _rnd.getRandomNumber(i - 1);
 			offsets[i] = offsets[j];
 			offsets[j] = i;
 		}
@@ -2099,7 +2099,7 @@ void Scumm::dissolveEffect(int width, int height) {
 		for (i = 1; i < w * h; i++) {
 			int j;
 
-			j = getRandomNumber(i - 1);
+			j = _rnd.getRandomNumber(i - 1);
 			offsets[i] = offsets[j];
 			offsets[j] = offsets2[i];
 		}
diff --git a/scumm/saveload.cpp b/scumm/saveload.cpp
index bedb3eebb9..33ecf348bf 100644
--- a/scumm/saveload.cpp
+++ b/scumm/saveload.cpp
@@ -431,6 +431,7 @@ void Scumm::saveOrLoad(Serializer *s)
 
 		MKLINE(Scumm, _screenEffectFlag, sleByte),
 
+		// FIXME: remove when new savegame system is implemented
 		MKLINE(Scumm, _randSeed1, sleUint32),
 		MKLINE(Scumm, _randSeed2, sleUint32),
 
@@ -545,6 +546,7 @@ void Scumm::saveOrLoad(Serializer *s)
 
 		MKLINE(Scumm, _screenEffectFlag, sleByte),
 
+		// FIXME: remove when new savegame system is implemented
 		MKLINE(Scumm, _randSeed1, sleUint32),
 		MKLINE(Scumm, _randSeed2, sleUint32),
 
diff --git a/scumm/script_v1.cpp b/scumm/script_v1.cpp
index cbf17a5a60..bd67df81d7 100644
--- a/scumm/script_v1.cpp
+++ b/scumm/script_v1.cpp
@@ -1134,7 +1134,7 @@ void Scumm::o5_ifNotState()
 void Scumm::o5_getRandomNr()
 {
 	getResultPos();
-	setResult(getRandomNumber(getVarOrDirectByte(0x80)));
+	setResult(_rnd.getRandomNumber(getVarOrDirectByte(0x80)));
 }
 
 void Scumm::o5_getScriptRunning()
diff --git a/scumm/script_v2.cpp b/scumm/script_v2.cpp
index 8e631ec1dd..49beb10f1a 100644
--- a/scumm/script_v2.cpp
+++ b/scumm/script_v2.cpp
@@ -1209,7 +1209,7 @@ void Scumm::o6_loadRoomWithEgo()
 void Scumm::o6_getRandomNumber()
 {
 	int rnd;
-	rnd = getRandomNumber(pop());
+	rnd = _rnd.getRandomNumber(pop());
 	_vars[VAR_V6_RANDOM_NR] = rnd;
 	push(rnd);
 }
@@ -1218,7 +1218,7 @@ void Scumm::o6_getRandomNumberRange()
 {
 	int max = pop();
 	int min = pop();
-	int rnd = getRandomNumberRng(min, max);
+	int rnd = _rnd.getRandomNumberRng(min, max);
 	_vars[VAR_V6_RANDOM_NR] = rnd;
 	push(rnd);
 }
diff --git a/scumm/scumm.h b/scumm/scumm.h
index 50247319ce..61d92896a2 100644
--- a/scumm/scumm.h
+++ b/scumm/scumm.h
@@ -27,6 +27,7 @@
 #include "common/gameDetector.h"
 #include "common/timer.h"
 #include "common/file.h"
+#include "common/util.h"
 
 class GameDetector;
 class NewGui;
@@ -351,10 +352,8 @@ public:
 	void convertKeysToClicks();
 
 	/* Random number generation */
-	uint32 _randSeed1, _randSeed2;
-	void initRandSeeds();
-	uint getRandomNumber(uint max);
-	uint getRandomNumberRng(uint min, uint max);
+	uint32 _randSeed1, _randSeed2; // FIXME: can be removed when new savegame system is implemented
+	RandomSource _rnd;
 
 	/* Core variable definitions */
 	byte _gameId;
diff --git a/scumm/scummvm.cpp b/scumm/scummvm.cpp
index 511fe03a6d..3694bb1c4c 100644
--- a/scumm/scummvm.cpp
+++ b/scumm/scummvm.cpp
@@ -73,25 +73,6 @@ Engine *Engine_SCUMM_create(GameDetector *detector, OSystem *syst)
 	return engine;
 }
 
-void Scumm::initRandSeeds()
-{
-	_randSeed1 = 0xA943DE33;
-	_randSeed2 = 0x37A9ED29;
-}
-
-uint Scumm::getRandomNumber(uint max)
-{
-	/* TODO: my own random number generator */
-	_randSeed1 = 0xDEADBF03 * (_randSeed1 + 1);
-	_randSeed1 = (_randSeed1 >> 13) | (_randSeed1 << 19);
-	return _randSeed1 % (max + 1);
-}
-
-uint Scumm::getRandomNumberRng(uint min, uint max)
-{
-	return getRandomNumber(max - min) + min;
-}
-
 Scumm::Scumm (GameDetector *detector, OSystem *syst) 
 	: Engine(detector, syst), _pauseDialog(0), _optionsDialog(0), _saveLoadDialog(0)
 {
@@ -118,6 +99,10 @@ Scumm::Scumm (GameDetector *detector, OSystem *syst)
 	_dynamicRoomOffsets = 0;
 	_shakeEnabled = 0;
 
+	// FIXME: remove when new savegame system is implemented
+	_randSeed1 = 0xA943DE33;
+	_randSeed2 = 0x37A9ED29;
+
 	if (_gameId == GID_ZAK256) {	// FmTowns is 320x240
 		_realWidth = 320;
 		_realHeight = 240;
@@ -404,7 +389,7 @@ int Scumm::scummLoop(int delta)
 
 	// Randomize the PRNG by calling it at regular intervals. This ensures
 	// that it will be in a different state each time you run the program.
-	getRandomNumber(2);
+	_rnd.getRandomNumber(2);
 
 	_vars[VAR_TMR_1] += delta;
 	_vars[VAR_TMR_2] += delta;
@@ -1589,8 +1574,6 @@ void Scumm::launch()
 
 	readIndexFile();
 
-	initRandSeeds();
-
 	if (_features & GF_NEW_OPCODES)
 		setupOpcodes2();
 	else