wip rng

Author: Entroper

FF1Lib/FF1Lib.csproj

@@ -55,7 +55,7 @@
   <ItemGroup>
     <PackageReference Include="Newtonsoft.Json" Version="11.0.2" />
     <PackageReference Include="Patcher6502" Version="0.3.0" />
-    <PackageReference Include="RomUtilities" Version="2.2.0" />
+    <PackageReference Include="RomUtilities" Version="3.1.0" />
   </ItemGroup>
 
   <ItemGroup>

FF1Lib/FF1Rom.cs

@@ -106,6 +106,7 @@ public void Randomize(Blob seed, Flags flags, Preferences preferences)
 			FixWarpBug(); // The warp bug must be fixed for magic level shuffle and spellcrafter
 			SeparateUnrunnables();
 			UpdateDialogs();
+			MoveSmokeSpriteVariables();
 
 			flags = Flags.ConvertAllTriState(flags, rng);
 

FF1Lib/Hacks.cs

@@ -41,6 +41,25 @@ public partial class FF1Rom : NesRom
 		public const string BattleBoxUndrawFrames = "04"; // 2/3 normal (Must  divide 12)
 		public const string BattleBoxUndrawRows = "03";
 
+		public const int SmokeSpriteReplaceStart = 0x317E9;
+		public const int SmokeSpriteReplaceEnd = 0x31A2C;
+
+		public void MoveSmokeSpriteVariables()
+		{
+			// This moves some temporary memory locations used to draw the smoke effect sprites
+			// in battle to the same locations used to store attacker stats.  These can overwrite
+			// each other without issue, and it frees up some space for a few bytes of RNG state.
+			var smokeSpriteCode = Get(SmokeSpriteReplaceStart, SmokeSpriteReplaceEnd - SmokeSpriteReplaceStart);
+
+			smokeSpriteCode.ReplaceInPlace(Blob.FromUShorts(new ushort[] { 0x68AF }), Blob.FromUShorts(new ushort[] { 0x686C }));
+			smokeSpriteCode.ReplaceInPlace(Blob.FromUShorts(new ushort[] { 0x68B1 }), Blob.FromUShorts(new ushort[] { 0x686E }));
+			smokeSpriteCode.ReplaceInPlace(Blob.FromUShorts(new ushort[] { 0x68B3 }), Blob.FromUShorts(new ushort[] { 0x6870 }));
+			smokeSpriteCode.ReplaceInPlace(Blob.FromUShorts(new ushort[] { 0x68B4 }), Blob.FromUShorts(new ushort[] { 0x6871 }));
+			smokeSpriteCode.ReplaceInPlace(Blob.FromUShorts(new ushort[] { 0x68B5 }), Blob.FromUShorts(new ushort[] { 0x6872 }));
+
+			Put(SmokeSpriteReplaceStart, smokeSpriteCode);
+		}
+
 		// Required for npc quest item randomizing
 		public void PermanentCaravan()
 		{

FF1Lib/asm/LCG.asm

@@ -0,0 +1,7 @@
+; Linear Congruential Generator (better random number generator)
+; https://en.wikipedia.org/wiki/Linear_congruential_generator
+; This is a simple but effective RNG with a much longer period than FF1's.
+
+; A research paper on selecting good parameters for the multiplier:
+; https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.34.1024&rep=rep1&type=pdf
+

FF1R/FF1R.csproj

@@ -13,7 +13,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="RomUtilities" Version="2.2.0" />
+    <PackageReference Include="RomUtilities" Version="3.1.0" />
   </ItemGroup>
 
   <ItemGroup>

FFR.Common/FFR.Common.csproj

@@ -2,7 +2,7 @@
 
   <ItemGroup>
     <PackageReference Include="Newtonsoft.Json" Version="11.0.2" />
-    <PackageReference Include="RomUtilities" Version="2.2.0" />
+    <PackageReference Include="RomUtilities" Version="3.1.0" />
   </ItemGroup>
 
   <ItemGroup>