- Added the frandom decorate function, which is exactly like random except

that it works with floating point instead of integers.


SVN r1797 (trunk)

docs/rh-log.txt

@@ -1,4 +1,6 @@
 September 5, 2009
+- Added the frandom decorate function, which is exactly like random except
+  that it works with floating point instead of integers.
 - Split the bounce types completely into separate flags and consolidated
   the various bounce-related flags spread across the different Actor flags
   field into a single BounceFlags field.

src/sc_man.h

@@ -209,6 +209,7 @@ enum
 	TK_Abs,
 	TK_Random,
 	TK_Random2,
+	TK_FRandom,
 
 	TK_LastToken
 };

src/sc_man_scanner.re

@@ -147,6 +147,7 @@ std2:
 		'abs'						{ RET(TK_Abs); }
 		'random'					{ RET(TK_Random); }
 		'random2'					{ RET(TK_Random2); }
+		'frandom'					{ RET(TK_FRandom); }
 
 		L (L|D)*					{ RET(TK_Identifier); }
 

src/thingdef/thingdef_exp.cpp

@@ -359,6 +359,29 @@ static FxExpression *ParseExpression0 (FScanner &sc, const PClass *cls)
 
 		return new FxRandom(rng, min, max, sc);
 	}
+	else if (sc.CheckToken(TK_FRandom))
+	{
+		FRandom *rng;
+
+		if (sc.CheckToken('['))
+		{
+			sc.MustGetToken(TK_Identifier);
+			rng = FRandom::StaticFindRNG(sc.String);
+			sc.MustGetToken(']');
+		}
+		else
+		{
+			rng = &pr_exrandom;
+		}
+		sc.MustGetToken('(');
+
+		FxExpression *min = ParseExpressionM (sc, cls);
+		sc.MustGetToken(',');
+		FxExpression *max = ParseExpressionM (sc, cls);
+		sc.MustGetToken(')');
+
+		return new FxFRandom(rng, min, max, sc);
+	}
 	else if (sc.CheckToken(TK_Random2))
 	{
 		FRandom *rng;

src/thingdef/thingdef_exp.h

@@ -540,6 +540,7 @@ public:
 
 class FxRandom : public FxExpression
 {
+protected:
 	FRandom * rng;
 	FxExpression *min, *max;
 
@@ -552,7 +553,18 @@ public:
 	ExpVal EvalExpression (AActor *self);
 };
 
+//==========================================================================
+//
+//
+//
+//==========================================================================
 
+class FxFRandom : public FxRandom
+{
+public:
+	FxFRandom(FRandom *, FxExpression *mi, FxExpression *ma, const FScriptPosition &pos);
+	ExpVal EvalExpression (AActor *self);
+};
 
 //==========================================================================
 //

src/thingdef/thingdef_expression.cpp

@@ -1661,7 +1661,6 @@ ExpVal FxRandom::EvalExpression (AActor *self)
 		int minval = min->EvalExpression (self).GetInt();
 		int maxval = max->EvalExpression (self).GetInt();
 
-
 		if (maxval < minval)
 		{
 			swap (maxval, minval);
@@ -1676,6 +1675,53 @@ ExpVal FxRandom::EvalExpression (AActor *self)
 	return val;
 }
 
+//==========================================================================
+//
+//
+//
+//==========================================================================
+FxFRandom::FxFRandom(FRandom *r, FxExpression *mi, FxExpression *ma, const FScriptPosition &pos)
+: FxRandom(r, NULL, NULL, pos)
+{
+	if (mi != NULL && ma != NULL)
+	{
+		min = mi;
+		max = ma;
+	}
+}
+
+//==========================================================================
+//
+//
+//
+//==========================================================================
+
+ExpVal FxFRandom::EvalExpression (AActor *self)
+{
+	ExpVal val;
+	val.Type = VAL_Float;
+	int random = (*rng)(0x40000000);
+	double frandom = random / double(0x40000000);
+
+	if (min != NULL && max != NULL)
+	{
+		double minval = min->EvalExpression (self).GetFloat();
+		double maxval = max->EvalExpression (self).GetFloat();
+
+		if (maxval < minval)
+		{
+			swap (maxval, minval);
+		}
+
+		val.Float = frandom * (maxval - minval) + minval;
+	}
+	else
+	{
+		val.Float = frandom;
+	}
+	return val;
+}
+
 //==========================================================================
 //
 //