Update RNG logic

Keep the PRNG object in the state instead of previousRandom.
The shuffle logic is kept as is.

Author: PiOverFour

src/engine/Story.ts

@@ -1189,15 +1189,15 @@ export class Story extends InkObject {
                 ". The maximum must be larger"
             );
 
-          let resultSeed = this.state.storySeed + this.state.previousRandom;
+          let resultSeed = this.state.previousRandom;
           let random = new PRNG(resultSeed);
 
           let nextRandom = random.next();
           let chosenValue = (nextRandom % randomRange) + minInt.value;
           this.state.PushEvaluationStack(new IntValue(chosenValue));
 
           // Next random number (rather than keeping the Random object around)
-          this.state.previousRandom = nextRandom;
+          this.state.previousRandom = random.nextSeed();
           break;
         }
 
@@ -1349,7 +1349,7 @@ export class Story extends InkObject {
             newList = new InkList();
           } else {
             // Generate a random index for the element to take
-            let resultSeed = this.state.storySeed + this.state.previousRandom;
+            let resultSeed = this.state.previousRandom;
             let random = new PRNG(resultSeed);
 
             let nextRandom = random.next();
@@ -1377,7 +1377,7 @@ export class Story extends InkObject {
             newList = new InkList(randomItem.Key.originName, this);
             newList.Add(randomItem.Key, randomItem.Value);
 
-            this.state.previousRandom = nextRandom;
+            this.state.previousRandom = random.nextSeed();
           }
 
           this.state.PushEvaluationStack(new ListValue(newList));