configurable blend weight

common/src/main/java/com/dfsek/terra/api/util/mutable/MutableBoolean.java

@@ -0,0 +1,20 @@
+package com.dfsek.terra.api.util.mutable;
+
+public class MutableBoolean implements MutablePrimitive<Boolean> {
+    private boolean value;
+
+    @Override
+    public Boolean get() {
+        return value;
+    }
+
+    @Override
+    public void set(Boolean value) {
+        this.value = value;
+    }
+
+    public boolean invert() {
+        value = !value;
+        return value;
+    }
+}

common/src/main/java/com/dfsek/terra/api/util/mutable/MutableDouble.java

@@ -0,0 +1,37 @@
+package com.dfsek.terra.api.util.mutable;
+
+public class MutableDouble extends MutableNumber<Double> {
+    public MutableDouble(Double value) {
+        super(value);
+    }
+
+    @Override
+    public void increment() {
+        add(1d);
+    }
+
+    @Override
+    public void decrement() {
+        subtract(1d);
+    }
+
+    @Override
+    public void add(Double add) {
+        value += add;
+    }
+
+    @Override
+    public void multiply(Double mul) {
+        value *= mul;
+    }
+
+    @Override
+    public void subtract(Double sub) {
+        value -= sub;
+    }
+
+    @Override
+    public void divide(Double divide) {
+        value /= divide;
+    }
+}

common/src/main/java/com/dfsek/terra/api/util/mutable/MutableInteger.java

@@ -10,7 +10,7 @@ public class MutableInteger extends MutableNumber<Integer> {
     }
 
     public void decrement() {
-        add(-1);
+        subtract(1);
     }
 
     @Override

common/src/main/java/com/dfsek/terra/config/builder/GeneratorBuilder.java

@@ -40,12 +40,18 @@ public class GeneratorBuilder {
 
     private int blendStep;
 
+    private double blendWeight;
+
     public WorldGenerator build(long seed) {
         synchronized(gens) {
-            return gens.computeIfAbsent(seed, k -> new WorldGenerator(seed, noiseEquation, elevationEquation, varScope, noiseBuilderMap, palettes, slantPalettes, noise2d, base, biomeNoise.build((int) seed), elevationWeight, blendDistance, blendStep));
+            return gens.computeIfAbsent(seed, k -> new WorldGenerator(seed, noiseEquation, elevationEquation, varScope, noiseBuilderMap, palettes, slantPalettes, noise2d, base, biomeNoise.build((int) seed), elevationWeight, blendDistance, blendStep, blendWeight));
         }
     }
 
+    public void setBlendWeight(double blendWeight) {
+        this.blendWeight = blendWeight;
+    }
+
     public void setBlendStep(int blendStep) {
         this.blendStep = blendStep;
     }

common/src/main/java/com/dfsek/terra/config/factories/BiomeFactory.java

@@ -30,6 +30,7 @@ public class BiomeFactory implements TerraFactory<BiomeTemplate, TerraBiome> {
         generatorBuilder.setBiomeNoise(template.getBiomeNoise());
         generatorBuilder.setBlendDistance(template.getBlendDistance());
         generatorBuilder.setBlendStep(template.getBlendStep());
+        generatorBuilder.setBlendWeight(template.getBlendWeight());
 
 
         return new UserDefinedBiome(template.getVanilla(), generatorBuilder, template);

common/src/main/java/com/dfsek/terra/config/templates/BiomeTemplate.java

@@ -75,7 +75,13 @@ public class BiomeTemplate extends AbstractableTemplate implements ValidatedConf
     @Default
     private int blendDistance = 3;
 
+    @Value("blend.weight")
+    @Abstractable
+    @Default
+    private double blendWeight = 1;
+
     @Value("blend.step")
+    @Abstractable
     @Default
     private int blendStep = 4;
 
@@ -170,6 +176,10 @@ public class BiomeTemplate extends AbstractableTemplate implements ValidatedConf
         return tags;
     }
 
+    public double getBlendWeight() {
+        return blendWeight;
+    }
+
     public int getColor() {
         return color;
     }

common/src/main/java/com/dfsek/terra/generation/config/WorldGenerator.java

@@ -35,8 +35,9 @@ public class WorldGenerator implements Generator {
     private final double elevationWeight;
     private final int blendDistance;
     private final int blendStep;
+    private final double blendWeight;
 
-    public WorldGenerator(long seed, String equation, String elevateEquation, Scope vScope, Map<String, NoiseBuilder> noiseBuilders, PaletteHolder palettes, PaletteHolder slantPalettes, boolean noise2d, double base, NoiseSampler biomeNoise, double elevationWeight, int blendDistance, int blendStep) {
+    public WorldGenerator(long seed, String equation, String elevateEquation, Scope vScope, Map<String, NoiseBuilder> noiseBuilders, PaletteHolder palettes, PaletteHolder slantPalettes, boolean noise2d, double base, NoiseSampler biomeNoise, double elevationWeight, int blendDistance, int blendStep, double blendWeight) {
         this.palettes = palettes;
         this.slantPalettes = slantPalettes;
 
@@ -46,6 +47,7 @@ public class WorldGenerator implements Generator {
         this.elevationWeight = elevationWeight;
         this.blendDistance = blendDistance;
         this.blendStep = blendStep;
+        this.blendWeight = blendWeight;
 
         Parser p = new Parser();
         p.registerFunction("rand", new RandomFunction());
@@ -104,7 +106,7 @@ public class WorldGenerator implements Generator {
 
     @Override
     public double getWeight() {
-        return 1;
+        return blendWeight;
     }
 
     @Override