From f3476c5cc8ca220d976686778bcf0a598582dcd7 Mon Sep 17 00:00:00 2001
From: Astrash <astrash@atr.sh>
Date: Sun, 7 Jan 2024 17:02:08 +1100
Subject: [PATCH] Add feature stage blending

---
 .../feature/FeatureGenerationStage.java       | 15 +++++++++++--
 .../feature/config/FeatureStageTemplate.java  | 21 ++++++++++++++++++-
 2 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/common/addons/generation-stage-feature/src/main/java/com/dfsek/terra/addons/generation/feature/FeatureGenerationStage.java b/common/addons/generation-stage-feature/src/main/java/com/dfsek/terra/addons/generation/feature/FeatureGenerationStage.java
index 6baf88b7a..123107d15 100644
--- a/common/addons/generation-stage-feature/src/main/java/com/dfsek/terra/addons/generation/feature/FeatureGenerationStage.java
+++ b/common/addons/generation-stage-feature/src/main/java/com/dfsek/terra/addons/generation/feature/FeatureGenerationStage.java
@@ -12,6 +12,7 @@ import java.util.Random;
 
 import com.dfsek.terra.addons.generation.feature.config.BiomeFeatures;
 import com.dfsek.terra.api.Platform;
+import com.dfsek.terra.api.noise.NoiseSampler;
 import com.dfsek.terra.api.properties.PropertyKey;
 import com.dfsek.terra.api.registry.key.StringIdentifiable;
 import com.dfsek.terra.api.util.Rotation;
@@ -31,13 +32,20 @@ public class FeatureGenerationStage implements GenerationStage, StringIdentifiab
 
     private final int resolution;
     private final PropertyKey<BiomeFeatures> biomeFeaturesKey;
+    private final NoiseSampler blendSampler;
+    private final boolean doBlending;
+    private final double blendAmplitude;
 
-    public FeatureGenerationStage(Platform platform, String id, int resolution, PropertyKey<BiomeFeatures> biomeFeaturesKey) {
+    public FeatureGenerationStage(Platform platform, String id, int resolution, PropertyKey<BiomeFeatures> biomeFeaturesKey,
+                                  NoiseSampler blendSampler, double blendAmplitude) {
         this.platform = platform;
         this.id = id;
         this.profile = "feature_stage:" + id;
         this.resolution = resolution;
         this.biomeFeaturesKey = biomeFeaturesKey;
+        this.blendSampler = blendSampler;
+        this.doBlending = blendAmplitude != 0d;
+        this.blendAmplitude = blendAmplitude;
     }
 
     @Override
@@ -52,7 +60,10 @@ public class FeatureGenerationStage implements GenerationStage, StringIdentifiab
                 int tx = cx + chunkX;
                 int tz = cz + chunkZ;
                 world.getBiomeProvider()
-                    .getColumn(tx, tz, world)
+                    .getColumn(
+                        tx + (doBlending ? (int) (blendSampler.noise(seed, tx, tz) * blendAmplitude) : 0),
+                        tz + (doBlending ? (int) (blendSampler.noise(seed+1, tx, tz) * blendAmplitude) : 0),
+                        world)
                     .forRanges(resolution, (min, max, biome) -> {
                         for(int subChunkX = 0; subChunkX < resolution; subChunkX++) {
                             for(int subChunkZ = 0; subChunkZ < resolution; subChunkZ++) {
diff --git a/common/addons/generation-stage-feature/src/main/java/com/dfsek/terra/addons/generation/feature/config/FeatureStageTemplate.java b/common/addons/generation-stage-feature/src/main/java/com/dfsek/terra/addons/generation/feature/config/FeatureStageTemplate.java
index ffc077f1a..d0fae0e1f 100644
--- a/common/addons/generation-stage-feature/src/main/java/com/dfsek/terra/addons/generation/feature/config/FeatureStageTemplate.java
+++ b/common/addons/generation-stage-feature/src/main/java/com/dfsek/terra/addons/generation/feature/config/FeatureStageTemplate.java
@@ -8,6 +8,7 @@ import com.dfsek.tectonic.api.exception.ValidationException;
 
 import com.dfsek.terra.addons.generation.feature.FeatureGenerationStage;
 import com.dfsek.terra.api.Platform;
+import com.dfsek.terra.api.noise.NoiseSampler;
 import com.dfsek.terra.api.properties.PropertyKey;
 import com.dfsek.terra.api.world.chunk.generation.stage.GenerationStage;
 
@@ -22,6 +23,24 @@ public class FeatureStageTemplate implements ObjectTemplate<GenerationStage>, Va
     @Default
     private int resolution = 4;
 
+    @Value("blend.sampler")
+    @Default
+    private NoiseSampler blendSampler = new NoiseSampler() {
+        @Override
+        public double noise(long seed, double x, double y) {
+            return 0;
+        }
+
+        @Override
+        public double noise(long seed, double x, double y, double z) {
+            return 0;
+        }
+    };
+
+    @Value("blend.amplitude")
+    @Default
+    private double blendAmplitude = 0d;
+
     public FeatureStageTemplate(Platform platform, PropertyKey<BiomeFeatures> biomeFeaturesKey) {
         this.platform = platform;
         this.biomeFeaturesKey = biomeFeaturesKey;
@@ -30,7 +49,7 @@ public class FeatureStageTemplate implements ObjectTemplate<GenerationStage>, Va
 
     @Override
     public FeatureGenerationStage get() {
-        return new FeatureGenerationStage(platform, id, resolution, biomeFeaturesKey);
+        return new FeatureGenerationStage(platform, id, resolution, biomeFeaturesKey, blendSampler, blendAmplitude);
     }
 
     @Override