YarnSpinner loading from line

README.txt

To set this up in Unity, it needs to:
1. have a reference to the DialogueRunner in the scene
2. be added to the Dialogue Views in the DialogueRunner
3. MAKE SURE THAT Yarn.LineJumper.asmdef and YarnLineJumper.cs ARE IN THEIR OWN SUBFOLDER

(This is for 2.2.2+)

To save a point, save integer returned from CurrentProgramCounter() somewhere.
To load a point, use LoadProgramCounter() with the node string name and integer saved from CurrentProgramCounter().

Yarn.LineJumper.asmdef

{
    "name": "Yarn.LineJumper",
    "rootNamespace": "",
    "references": [
        "YarnSpinner.Unity"
    ],
    "includePlatforms": [],
    "excludePlatforms": [],
    "allowUnsafeCode": false,
    "overrideReferences": true,
    "precompiledReferences": [
        "Yarn.Google.Protobuf.dll",
        "YarnSpinner.dll"
    ],
    "autoReferenced": true,
    "defineConstraints": [],
    "versionDefines": [],
    "noEngineReferences": false
}

YarnLineJumper.cs

using System;
using Yarn;
using Yarn.Unity;
using static Yarn.Instruction.Types;

namespace SaveSystem {
    public class YarnLineJumper : DialogueViewBase
    {
        public DialogueRunner diaRunner;

        // Name of the label being inserted
        string operandName = "load_jump";

        // Keep these for modifications and access
        Program program;
        Node currentNode;

        // When saving specific instruction, use this
        int linesRun;

        public void Awake()
        {
            diaRunner.SetProject(Instantiate(diaRunner.yarnProject));
            program = diaRunner.yarnProject.Program;
            diaRunner.onNodeStart.AddListener((string input) => {
                this.linesRun = 0;
                currentNode = program.Nodes[diaRunner.CurrentNodeName];
            });

        }

        public void LoadProgramCounter(string node, int line)
        {
            // Jump Instruction being inserted
            Instruction jumpInstruction = new Instruction();
            jumpInstruction.Opcode = OpCode.JumpTo;
            jumpInstruction.Operands.Add(new Operand(operandName));

            // Acquire the shennanigans
            currentNode = program.Nodes[node];

            // Tell it where to jump
            if (!currentNode.Labels.ContainsKey(operandName))
            {
                foreach (string key in currentNode.Labels.Keys)
                {
                    currentNode.Labels[key] += 1;
                }
                currentNode.Labels.Add(operandName, line);
                currentNode.Instructions.Insert(0, jumpInstruction);
            }
            else
            {
                currentNode.Labels[operandName] = line;
                currentNode.Instructions[0] = jumpInstruction;
            }

            diaRunner.Stop();
            diaRunner.Dialogue.SetProgram(program);
            diaRunner.StartDialogue(node);
            currentNode.Labels[operandName] = 1;

            // Set the runLineCount here to allow accurate saving
            linesRun = 0;
            for (int i = 0; i < line; i++)
            {
                if (currentNode.Instructions[i].Opcode == OpCode.RunLine)
                    linesRun++;
            }
        }

        public int CurrentProgramCounter()
        {
            int programCounter = 0;
            int runLineCount = 0;
            while (runLineCount != linesRun)
            {
                if (currentNode.Instructions[programCounter].Opcode == OpCode.RunLine)
                    runLineCount++;
                programCounter++;
            }
            if (!(currentNode.Instructions[0].Opcode == OpCode.JumpTo
                && String.ReferenceEquals(currentNode.Instructions[0].Operands[0].StringValue, operandName)))
                programCounter++;
            return programCounter;
        }

        public override void RunLine(LocalizedLine dialogueLine, Action onDialogueLineFinished)
        {
            linesRun++;
        }
    }
}