Added a ImmunityExtension

Common/Defs/GeneDefs/GeneDefs_Diseases.xml

@@ -202,4 +202,21 @@
         </modExtensions>
     </GeneDef>
 
+    <GeneDef ParentName="RJWGeneDisease">
+        <defName>rjw_genes_stretcher</defName>
+        <label>genetic stretcher</label>
+        <description>Pawns with this gene have a chance to make sexual partners prefer large genitalia as part of their genetics.</description>
+        <iconPath>UI/Icons/ColonistBar/Idle</iconPath>
+        <biostatCpx>1</biostatCpx>
+        <biostatMet>0</biostatMet>
+        <displayOrderInCategory>12</displayOrderInCategory>
+        <modExtensions>
+            <li Class="RJW_Genes.ImmunityAgainstGenesExtension">
+                <givesImmunityAgainst>
+                    <li>rjw_genes_size_blinded</li>
+                </givesImmunityAgainst>
+            </li>
+        </modExtensions>
+    </GeneDef>
+
 </Defs>

Source/Genes/Diseases/Defs/ImmunityAgainstGenesExtension.cs

@@ -0,0 +1,19 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Verse;
+
+namespace RJW_Genes
+{
+    public class ImmunityAgainstGenesExtension : DefModExtension
+    {
+        /// <summary>
+        /// A list of the exact defnames of disease-genes that this extension will make immune against.
+        /// Must perfectly match!
+        /// </summary>
+        public List<string> givesImmunityAgainst;
+    }
+
+}

Source/Genes/Diseases/DiseaseHelper.cs

@@ -0,0 +1,111 @@
+using rjw;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Verse;
+
+namespace RJW_Genes
+{
+    public static class DiseaseHelper
+    {
+
+        /// <summary>
+        /// Checks for a pawn if it is immune against a disease.
+        /// </summary>
+        /// <param name="pawn">The pawn for which immunity is checked</param>
+        /// <param name="disease">The genetic disease that is checked against</param>
+        /// <returns>True if the pawn is immune, false if the pawn can be infected by it.</returns>
+        public static bool IsImmuneAgainstGeneticDisease(Pawn pawn, GeneDef disease)
+        {
+            // Case 1: Something is null / not working, return Immune (to have less follow up effects)
+            if (pawn == null || pawn.genes == null) return true;
+            if (disease == null) return true;
+            // Case 1.B: Dead people can spread, but not receive, diseases.
+            if (pawn.Dead) return true;
+
+            // Case 2: The pawn has general genetic immunity to diseases
+            if (GeneUtility.HasGeneNullCheck(pawn, GeneDefOf.rjw_genes_genetic_disease_immunity))
+                return true;
+
+            // Case 3: The pawn already has the genetic disease
+            if (GeneUtility.HasGeneNullCheck(pawn, disease))
+                return true;
+
+            // Case 4: Check all genes if one of them has the Immunity Extension that covers the GeneDef
+            List<Gene> genes = pawn.genes.GenesListForReading;
+            genes = genes.Where(x => pawn.genes.HasActiveGene(x.def)).ToList();
+
+            foreach (Gene gene in genes)
+            {
+                ImmunityAgainstGenesExtension ext = gene.def.GetModExtension<ImmunityAgainstGenesExtension>();
+                if (ext != null) { 
+                    foreach (string defname in ext.givesImmunityAgainst)
+                        if (disease.defName == defname)
+                            return true;
+                }
+            }
+
+            // Case 5: Nothing special happens, so return false (not immune)
+            return false;
+        }
+
+        /// <summary>
+        /// Returns all active Genes with the `GeneticDiseaseExtension`.
+        /// </summary>
+        /// <param name="pawn"></param>
+        /// <returns>List of all active Genes with the `GeneticDiseaseExtension` in pawn</returns>
+        public static List<GeneDef> GetGeneticDiseaseGenes(Pawn pawn)
+        {
+            if (pawn != null && pawn.genes != null)
+            {
+                return pawn.genes
+                    .GenesListForReading
+                    .ConvertAll(gene => gene.def)
+                    .Where(genedef => pawn.genes.HasActiveGene(genedef))
+                    .Where(IsGeneticDiseaseGene)
+                    .ToList();
+            }
+
+            return new List<GeneDef>() { };
+        }
+
+        /// <summary>
+        /// Checks if the performed sex was penetrative. 
+        /// Condom check is not done here!
+        /// </summary>
+        /// <param name="props">The sexprops </param>
+        /// <returns></returns>
+        public static bool IsPenetrativeSex(SexProps props)
+        {
+            if (props == null) return false;
+
+            return props.sexType ==
+                xxx.rjwSextype.Vaginal
+                || props.sexType == xxx.rjwSextype.Anal
+                || props.sexType == xxx.rjwSextype.Oral
+                || props.sexType == xxx.rjwSextype.DoublePenetration
+                || props.sexType == xxx.rjwSextype.Fellatio
+                || props.sexType == xxx.rjwSextype.Sixtynine;
+        }
+
+        public static bool IsGeneticDiseaseGene(GeneDef geneDef)
+        {
+            if (geneDef == null) return false;
+            GeneticDiseaseExtension diseaseExt = geneDef.GetModExtension<GeneticDiseaseExtension>();
+            return diseaseExt != null;
+        }
+
+        public static float LookupDiseaseInfectionChance(GeneDef geneDef)
+        {
+            if (IsGeneticDiseaseGene(geneDef))
+            {
+                GeneticDiseaseExtension diseaseExt = geneDef.GetModExtension<GeneticDiseaseExtension>();
+                return diseaseExt != null ? diseaseExt.infectionChance : 0.0f;
+            }
+            else
+                return 0.0f;
+        }
+    }
+}

Source/Genes/Diseases/Patches/Patch_AftersexUtility_TransferGeneticDiseases.cs

@@ -29,7 +29,7 @@ namespace RJW_Genes.Genes.Diseases.Patches
             if (props.usedCondom) return;
 
             // Exit early if settings require penetrative sex, but this is not penetrative sex
-            if (!IsPenetrativeSex(props) && RJW_Genes_Settings.rjw_genes_genetic_disease_spread_only_on_penetrative_sex) return;
+            if (!DiseaseHelper.IsPenetrativeSex(props) && RJW_Genes_Settings.rjw_genes_genetic_disease_spread_only_on_penetrative_sex) return;
 
             ModLog.Debug($"Firing Patch_TransferGeneticDiseases for {pawn} and {partner}");
             TryTransferGeneticDiseases(pawn, partner, props);
@@ -38,74 +38,19 @@ namespace RJW_Genes.Genes.Diseases.Patches
 
         private static void TryTransferGeneticDiseases(Pawn infector, Pawn infected, SexProps props)
         {
-            if (infected.genes.HasActiveGene(GeneDefOf.rjw_genes_genetic_disease_immunity))
-            {
-                ModLog.Debug($"{infected} is immune to genetic diseases");
-                return;
-            }
-            if (infected.Dead)
-            {
-                // Dead people can spread, but not receive, diseases.
-                return;
-            }
             
-            foreach (GeneDef disease in GetGeneticDiseaseGenes(infector)) {
+            foreach (GeneDef disease in DiseaseHelper.GetGeneticDiseaseGenes(infector)) {
                 ModLog.Debug($"Found genetic disease {disease} in {infector}, trying to infect {infected}");
 
-                if (infected.genes.HasActiveGene(disease))
+                if (DiseaseHelper.IsImmuneAgainstGeneticDisease(infected,disease))
                     continue;
 
-                if ((new Random()).NextDouble() <= LookupDiseaseInfectionChance(disease))
+                if ((new Random()).NextDouble() <= DiseaseHelper.LookupDiseaseInfectionChance(disease))
                 {
                     infected.genes.AddGene(disease, !RJW_Genes_Settings.rjw_genes_genetic_disease_as_endogenes);
                 }
             }
         }
 
-        private static List<GeneDef> GetGeneticDiseaseGenes(Pawn pawn)
-        {
-            if (pawn != null && pawn.genes != null)
-            {
-                return pawn.genes
-                    .GenesListForReading
-                    .ConvertAll(gene => gene.def)
-                    .Where(genedef => pawn.genes.HasActiveGene(genedef))
-                    .Where(IsGeneticDiseaseGene)
-                    .ToList();
-            }
-
-            return new List<GeneDef>() { };
-        }
-
-        private static bool IsPenetrativeSex(SexProps props)
-        {
-            if (props == null) return false;
-
-            return props.sexType ==
-                xxx.rjwSextype.Vaginal
-                || props.sexType == xxx.rjwSextype.Anal
-                || props.sexType == xxx.rjwSextype.Oral
-                || props.sexType == xxx.rjwSextype.DoublePenetration
-                || props.sexType == xxx.rjwSextype.Fellatio
-                || props.sexType == xxx.rjwSextype.Sixtynine;
-        }
-
-        private static bool IsGeneticDiseaseGene(GeneDef geneDef)
-        {
-            if (geneDef == null) return false;
-            GeneticDiseaseExtension diseaseExt = geneDef.GetModExtension<GeneticDiseaseExtension>();
-            return diseaseExt != null;
-        }
-
-        private static float LookupDiseaseInfectionChance(GeneDef geneDef)
-        {
-            if (IsGeneticDiseaseGene(geneDef))
-            {
-                GeneticDiseaseExtension diseaseExt = geneDef.GetModExtension<GeneticDiseaseExtension>();
-                return diseaseExt != null ? diseaseExt.infectionChance : 0.0f;
-            } 
-            else 
-                return 0.0f;
-        }
     }
 }

Source/Rjw-Genes.csproj

@@ -76,6 +76,8 @@
     <Compile Include="Genes\Cum\Patch_LikesCumflation.cs" />
     <Compile Include="Genes\Damage\Gene_Elasticity.cs" />
     <Compile Include="Genes\Diseases\Defs\GeneticDiseaseExtension.cs" />
+    <Compile Include="Genes\Diseases\Defs\ImmunityAgainstGenesExtension.cs" />
+    <Compile Include="Genes\Diseases\DiseaseHelper.cs" />
     <Compile Include="Genes\Diseases\Genes\Gene_FluctualSexualNeed.cs" />
     <Compile Include="Genes\Diseases\Patches\Patch_AftersexUtility_TransferGeneticDiseases.cs" />
     <Compile Include="Genes\Diseases\Patches\Patch_SecondaryRomanceChanceFactor_Gene_SizeBlinded.cs" />