Merge branch 'ver/6.6.0' into dev/7.0-2

common/addons/config-noise-function/src/main/java/com/dfsek/terra/addons/noise/samplers/arithmetic/AdditionSampler.java

@@ -12,4 +12,14 @@ public class AdditionSampler extends BinaryArithmeticSampler {
     public double operate(double left, double right) {
         return left + right;
     }
+
+    @Override
+    public double[] operated(double[] left, double[] right) {
+        int dimensions = left.length;
+        double[] out = new double[dimensions];
+        for(int i = 0; i < dimensions; i++) {
+            out[i] = left[i] + right[i];
+        }
+        return out;
+    }
 }

common/addons/config-noise-function/src/main/java/com/dfsek/terra/addons/noise/samplers/arithmetic/BinaryArithmeticSampler.java

@@ -1,9 +1,10 @@
 package com.dfsek.terra.addons.noise.samplers.arithmetic;
 
+import com.dfsek.terra.api.noise.DerivativeNoiseSampler;
 import com.dfsek.terra.api.noise.NoiseSampler;
 
 
-public abstract class BinaryArithmeticSampler implements NoiseSampler {
+public abstract class BinaryArithmeticSampler implements DerivativeNoiseSampler {
     private final NoiseSampler left;
     private final NoiseSampler right;
 
@@ -12,6 +13,11 @@ public abstract class BinaryArithmeticSampler implements NoiseSampler {
         this.right = right;
     }
 
+    @Override
+    public boolean isDifferentiable() {
+        return DerivativeNoiseSampler.isDifferentiable(left) && DerivativeNoiseSampler.isDifferentiable(right);
+    }
+
     @Override
     public double noise(long seed, double x, double y) {
         return operate(left.noise(seed, x, y), right.noise(seed, x, y));
@@ -22,5 +28,17 @@ public abstract class BinaryArithmeticSampler implements NoiseSampler {
         return operate(left.noise(seed, x, y, z), right.noise(seed, x, y, z));
     }
 
+    @Override
+    public double[] noised(long seed, double x, double y) {
+        return operated(((DerivativeNoiseSampler)left).noised(seed, x, y), ((DerivativeNoiseSampler)right).noised(seed, x, y));
+    }
+
+    @Override
+    public double[] noised(long seed, double x, double y, double z) {
+        return operated(((DerivativeNoiseSampler)left).noised(seed, x, y, z), ((DerivativeNoiseSampler)right).noised(seed, x, y, z));
+    }
+
     public abstract double operate(double left, double right);
+
+    public abstract double[] operated(double[] left, double[] right);
 }

common/addons/config-noise-function/src/main/java/com/dfsek/terra/addons/noise/samplers/arithmetic/DivisionSampler.java

@@ -12,4 +12,15 @@ public class DivisionSampler extends BinaryArithmeticSampler {
     public double operate(double left, double right) {
         return left / right;
     }
+
+    @Override
+    public double[] operated(double[] left, double[] right) {
+        int dimensions = left.length;
+        double[] out = new double[dimensions];
+        out[0] = left[0] / right[0];
+        for(int i = 1; i < dimensions; i++) {
+            out[i] = (left[i] * right[0] - left[0] * right[i]) / (right[0] * right[0]);
+        }
+        return out;
+    }
 }

common/addons/config-noise-function/src/main/java/com/dfsek/terra/addons/noise/samplers/arithmetic/MaxSampler.java

@@ -12,4 +12,11 @@ public class MaxSampler extends BinaryArithmeticSampler {
     public double operate(double left, double right) {
         return Math.max(left, right);
     }
+
+    @Override
+    public double[] operated(double[] left, double[] right) {
+        double leftValue = left[0];
+        double rightValue = right[0];
+        return leftValue > rightValue ? left : right;
+    }
 }

common/addons/config-noise-function/src/main/java/com/dfsek/terra/addons/noise/samplers/arithmetic/MinSampler.java

@@ -12,4 +12,11 @@ public class MinSampler extends BinaryArithmeticSampler {
     public double operate(double left, double right) {
         return Math.min(left, right);
     }
+
+    @Override
+    public double[] operated(double[] left, double[] right) {
+        double leftValue = left[0];
+        double rightValue = right[0];
+        return leftValue < rightValue ? left : right;
+    }
 }

common/addons/config-noise-function/src/main/java/com/dfsek/terra/addons/noise/samplers/arithmetic/MultiplicationSampler.java

@@ -12,4 +12,15 @@ public class MultiplicationSampler extends BinaryArithmeticSampler {
     public double operate(double left, double right) {
         return left * right;
     }
+
+    @Override
+    public double[] operated(double[] left, double[] right) {
+        int dimensions = left.length;
+        double[] out = new double[dimensions];
+        out[0] = left[0] * right[0];
+        for(int i = 1; i < dimensions; i++) {
+            out[i] = left[i] * right[0] + left[0] * right[i];
+        }
+        return out;
+    }
 }

common/addons/config-noise-function/src/main/java/com/dfsek/terra/addons/noise/samplers/arithmetic/SubtractionSampler.java

@@ -12,4 +12,14 @@ public class SubtractionSampler extends BinaryArithmeticSampler {
     public double operate(double left, double right) {
         return left - right;
     }
+
+    @Override
+    public double[] operated(double[] left, double[] right) {
+        int dimensions = left.length;
+        double[] out = new double[dimensions];
+        for(int i = 0; i < dimensions; i++) {
+            out[i] = left[i] - right[i];
+        }
+        return out;
+    }
 }

common/addons/config-noise-function/src/main/java/com/dfsek/terra/addons/noise/samplers/noise/fractal/BrownianMotionSampler.java

@@ -7,6 +7,7 @@
 
 package com.dfsek.terra.addons.noise.samplers.noise.fractal;
 
+import com.dfsek.terra.api.noise.DerivativeNoiseSampler;
 import com.dfsek.terra.api.noise.NoiseSampler;
 import com.dfsek.terra.api.util.MathUtil;
 
@@ -52,4 +53,60 @@ public class BrownianMotionSampler extends FractalNoiseFunction {
 
         return sum;
     }
+
+    @Override
+    public boolean isDifferentiable() {
+        return DerivativeNoiseSampler.isDifferentiable(input);
+    }
+
+    @Override
+    public double[] getNoiseDerivativeRaw(long seed, double x, double y) {
+        double[] sum = {0, 0, 0};
+        double amp = fractalBounding;
+
+        for(int i = 0; i < octaves; i++) {
+            // This should only be called after `input` is verified as a `DerivativeNoiseSampler`
+            // so this should be a safe cast
+            double[] noise = ((DerivativeNoiseSampler) input).noised(seed++, x, y);
+            sum[0] += noise[0] * amp;
+
+            // Directional derivative of each octave can be subject to the same addition and product
+            // as per derivative sum and product rules in order to produce the correct final derivative
+            sum[1] += noise[1] * amp;
+            sum[2] += noise[2] * amp;
+
+            amp *= MathUtil.lerp(weightedStrength, 1.0, Math.min(noise[0] + 1, 2) * 0.5);
+
+            x *= lacunarity;
+            y *= lacunarity;
+            amp *= gain;
+        }
+
+        return sum;
+    }
+
+    @Override
+    public double[] getNoiseDerivativeRaw(long seed, double x, double y, double z) {
+        double[] sum = {0, 0, 0, 0};
+        double amp = fractalBounding;
+
+        for(int i = 0; i < octaves; i++) {
+            double[] noise = ((DerivativeNoiseSampler) input).noised(seed++, x, y, z);
+            sum[0] += noise[0] * amp;
+
+            // See comment in 2D version
+            sum[1] += noise[1] * amp;
+            sum[2] += noise[2] * amp;
+            sum[3] += noise[3] * amp;
+
+            amp *= MathUtil.lerp(weightedStrength, 1.0, (noise[0] + 1) * 0.5);
+
+            x *= lacunarity;
+            y *= lacunarity;
+            z *= lacunarity;
+            amp *= gain;
+        }
+
+        return sum;
+    }
 }

common/addons/config-noise-function/src/main/java/com/dfsek/terra/addons/noise/samplers/noise/fractal/FractalNoiseFunction.java

@@ -7,11 +7,11 @@
 
 package com.dfsek.terra.addons.noise.samplers.noise.fractal;
 
-import com.dfsek.terra.addons.noise.samplers.noise.NoiseFunction;
+import com.dfsek.terra.addons.noise.samplers.noise.DerivativeNoiseFunction;
 import com.dfsek.terra.api.noise.NoiseSampler;
 
 
-public abstract class FractalNoiseFunction extends NoiseFunction {
+public abstract class FractalNoiseFunction extends DerivativeNoiseFunction {
     protected final NoiseSampler input;
     protected double fractalBounding = 1 / 1.75;
     protected int octaves = 3;
@@ -52,4 +52,19 @@ public abstract class FractalNoiseFunction extends NoiseFunction {
     public void setWeightedStrength(double weightedStrength) {
         this.weightedStrength = weightedStrength;
     }
+
+    @Override
+    public boolean isDifferentiable() {
+        return false;
+    }
+
+    @Override
+    public double[] getNoiseDerivativeRaw(long seed, double x, double y) {
+        throw new UnsupportedOperationException("Implementation failed to check or set isDifferentiable correctly");
+    }
+
+    @Override
+    public double[] getNoiseDerivativeRaw(long seed, double x, double y, double z) {
+        throw new UnsupportedOperationException("Implementation failed to check or set isDifferentiable correctly");
+    }
 }

common/addons/config-noise-function/src/main/java/com/dfsek/terra/addons/noise/samplers/noise/simplex/SimplexStyleSampler.java

@@ -116,12 +116,12 @@ public abstract class SimplexStyleSampler extends DerivativeNoiseFunction {
 
     @Override
     public double[] getNoiseDerivativeRaw(long seed, double x, double y) {
-        return new double[]{ 0, 0, 0 };
+        throw new UnsupportedOperationException("Implementation failed to check or set isDifferentiable correctly");
     }
 
     @Override
     public double[] getNoiseDerivativeRaw(long seed, double x, double y, double z) {
-        return new double[]{ 0, 0, 0, 0 };
+        throw new UnsupportedOperationException("Implementation failed to check or set isDifferentiable correctly");
     }
 
     @Override

common/api/src/main/java/com/dfsek/terra/api/noise/DerivativeNoiseSampler.java

@@ -6,10 +6,7 @@ package com.dfsek.terra.api.noise;
 public interface DerivativeNoiseSampler extends NoiseSampler {
 
     static boolean isDifferentiable(NoiseSampler sampler) {
-        if(sampler instanceof DerivativeNoiseSampler dSampler) {
+        return sampler instanceof DerivativeNoiseSampler dSampler && dSampler.isDifferentiable();
-            return dSampler.isDifferentiable();
-        }
-        return false;
     }
 
     /**