begin work on terrain samplers

common/src/main/java/com/dfsek/terra/api/world/biome/Generator.java

@@ -2,6 +2,9 @@ package com.dfsek.terra.api.world.biome;
 
 import com.dfsek.terra.api.math.noise.NoiseSampler;
 import com.dfsek.terra.api.world.palette.Palette;
+import com.dfsek.terra.world.generation.math.samplers.terrain.TerrainSampler;
+
+import java.util.List;
 
 public interface Generator {
     /**
@@ -41,4 +44,6 @@ public interface Generator {
     double getElevationWeight();
 
     int getBlendStep();
+
+    List<TerrainSampler> getTerrainSamplers();
 }

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

@@ -4,6 +4,10 @@ import com.dfsek.terra.api.math.noise.NoiseSampler;
 import com.dfsek.terra.api.world.biome.Generator;
 import com.dfsek.terra.api.world.palette.Palette;
 import com.dfsek.terra.api.world.palette.holder.PaletteHolder;
+import com.dfsek.terra.world.generation.math.samplers.terrain.TerrainSampler;
+
+import java.util.Collections;
+import java.util.List;
 
 public class WorldGenerator implements Generator {
     @SuppressWarnings({"unchecked", "rawtypes", "RedundantSuppression"})
@@ -85,6 +89,11 @@ public class WorldGenerator implements Generator {
         return blendStep;
     }
 
+    @Override
+    public List<TerrainSampler> getTerrainSamplers() {
+        return Collections.emptyList();
+    }
+
     public Palette getSlantPalette(int y) {
         return slantPalettes.getPalette(y);
     }

common/src/main/java/com/dfsek/terra/world/generation/math/samplers/terrain/ExpressionSampler.java

@@ -0,0 +1,22 @@
+package com.dfsek.terra.world.generation.math.samplers.terrain;
+
+import com.dfsek.paralithic.Expression;
+import com.dfsek.terra.world.generation.math.interpolation.Interpolator3;
+
+public class ExpressionSampler implements TerrainSampler {
+    private final Expression expression;
+
+    public ExpressionSampler(Expression expression) {
+        this.expression = expression;
+    }
+
+    @Override
+    public Interpolator3 sample(double x, double y, double z) {
+        return (i, i1, i2) -> expression.evaluate(x, y, z);
+    }
+
+    @Override
+    public int getXResolution() {
+        return 1;
+    }
+}

common/src/main/java/com/dfsek/terra/world/generation/math/samplers/terrain/InterpolatedSampler.java

@@ -0,0 +1,31 @@
+package com.dfsek.terra.world.generation.math.samplers.terrain;
+
+import com.dfsek.terra.world.generation.math.interpolation.Interpolator3;
+
+public class InterpolatedSampler implements TerrainSampler {
+    private final InterpolatorSupplier supplier;
+
+    public InterpolatedSampler(InterpolatorSupplier supplier) {
+        this.supplier = supplier;
+    }
+
+    @Override
+    public Interpolator3 sample(double x, double y, double z) {
+        return null;
+    }
+
+    @Override
+    public int getXResolution() {
+        return supplier.getXResolution();
+    }
+
+    @Override
+    public int getYResolution() {
+        return supplier.getYResolution();
+    }
+
+    @Override
+    public int getZResolution() {
+        return supplier.getZResolution();
+    }
+}

common/src/main/java/com/dfsek/terra/world/generation/math/samplers/terrain/InterpolatorSupplier.java

@@ -0,0 +1,19 @@
+package com.dfsek.terra.world.generation.math.samplers.terrain;
+
+import com.dfsek.terra.world.generation.math.interpolation.Interpolator2;
+import com.dfsek.terra.world.generation.math.interpolation.Interpolator3;
+
+import java.util.function.Supplier;
+
+public interface InterpolatorSupplier {
+    int getXResolution();
+    int getYResolution();
+    int getZResolution();
+
+    Interpolator2 get(double t, double v0, double v1);
+
+    Interpolator3 get(double _000, double _100,
+                      double _010, double _110,
+                      double _001, double _101,
+                      double _011, double _111);
+}

common/src/main/java/com/dfsek/terra/world/generation/math/samplers/terrain/TerrainSampler.java

@@ -0,0 +1,22 @@
+package com.dfsek.terra.world.generation.math.samplers.terrain;
+
+import com.dfsek.terra.world.generation.math.interpolation.Interpolator2;
+import com.dfsek.terra.world.generation.math.interpolation.Interpolator3;
+
+public interface TerrainSampler {
+    Interpolator3 sample(double x, double y, double z);
+
+    default Interpolator2 sample(double x, double z) {
+        return (s, t) -> sample(x, 0, z).interpolate(s, 0, t);
+    }
+
+    int getXResolution();
+
+    default int getYResolution() {
+        return getXResolution();
+    }
+
+    default int getZResolution() {
+        return getXResolution();
+    }
+}