Draft for Mating Call

Source/Genes/Breeding/Patches/PatchMechBirth.cs

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+
+
+using System;
+using System.Collections.Generic;
+using System.Reflection;
+using System.Reflection.Emit;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using HarmonyLib;
+using rjw;
+
+namespace RJW_Genes
+{
+    /// <summary>
+    /// This Class patches the RJW-Mechbirth to not deal damage when the pawn has the MechBreeder Gene.
+    /// This harmony patch was kindly provided by 'shabalox' https://github.com/Shabalox/RJW_Genes_Addons/
+    /// </summary>
+    [HarmonyPatch(typeof(Hediff_MechanoidPregnancy), "GiveBirth")]
+    public static class PatchMechBirth
+    {
+        [HarmonyTranspiler]
+        public static IEnumerable<CodeInstruction> Transpiler(IEnumerable<CodeInstruction> instructions, ILGenerator il)
+        {
+            bool found_call = false;
+            bool found_skip = false;
+            Label skip_label = il.DefineLabel();
+            MethodInfo ismechbreeder = AccessTools.Method(typeof(GeneUtility), "IsMechbreeder");
+            foreach (CodeInstruction codeInstruction in instructions)
+            {
+                //Check if the first opcode after endfinally ldloc_0 is and in that case add the label to skip the code
+                if (found_skip && codeInstruction.opcode == OpCodes.Ldloc_0)
+                {
+                    codeInstruction.labels.Add(skip_label);
+                }
+                found_skip = false;
+                if (codeInstruction.opcode == OpCodes.Endfinally)
+                {
+                    found_skip = true;
+                }
+
+                yield return codeInstruction;
+
+                if (codeInstruction.opcode == OpCodes.Call)
+                {
+                    if (codeInstruction.operand.ToString() == "Boolean TryMakeFilth(Verse.IntVec3, Verse.Map, Verse.ThingDef, System.String, Int32, RimWorld.FilthSourceFlags)")
+                    {
+                        found_call = true;
+                    }
+                }
+                //Triggers after the pop opcode (after generating filth in c#).
+                else if (found_call)
+                {
+                    //Load pawn, call function to check if a mechbreeder, and skip past the part which does damage
+                    yield return new CodeInstruction(OpCodes.Ldloc_0, null);
+                    yield return new CodeInstruction(OpCodes.Call, ismechbreeder);
+                    yield return new CodeInstruction(OpCodes.Brtrue_S, skip_label);
+                    found_call = false;
+                }
+            }
+            yield break;
+        }
+    }
+}