add RandomGenerator parameter to Hittable#hit

src/main/java/eu/jonahbauer/raytracing/Main.java

@@ -24,6 +24,7 @@ public class Main {
 
         var renderer = SimpleRenderer.builder()
                 .withSamplesPerPixel(config.samples)
+                .withSpectralSamples(config.spectralSamples)
                 .withMaxDepth(config.depth)
                 .withIterative(config.iterative)
                 .withParallel(config.parallel)
@@ -45,7 +46,7 @@ public class Main {
         PNGImageWriter.sRGB.write(canvas, config.path);
     }
 
-    private record Config(@NotNull Example example, @NotNull Path path, boolean preview, boolean iterative, boolean parallel, int samples, int depth) {
+    private record Config(@NotNull Example example, @NotNull Path path, boolean preview, boolean iterative, boolean parallel, int samples, int spectralSamples, int depth) {
         public static @NotNull Config parse(@NotNull String @NotNull[] args) {
             IntFunction<Example> example = null;
             Path path = null;
@@ -53,6 +54,7 @@ public class Main {
             boolean iterative = false;
             boolean parallel = false;
             int samples = 1000;
+            int spectralSamples = 4;
             int depth = 50;
             int height = -1;
 
@@ -81,6 +83,15 @@ public class Main {
                             throw fail("value " + args[i] + " is not a valid integer");
                         }
                     }
+                    case "--spectral-samples" -> {
+                        if (i + 1 == args.length) throw fail("missing value for parameter --spectral-samples");
+                        try {
+                            spectralSamples = Integer.parseInt(args[++i]);
+                            if (spectralSamples <= 0) throw fail("spectral samples must be positive");
+                        } catch (NumberFormatException ex) {
+                            throw fail("value " + args[i] + " is not a valid integer");
+                        }
+                    }
                     case "--depth" -> {
                         if (i + 1 == args.length) throw fail("missing value for parameter --depth");
                         try {
@@ -112,7 +123,7 @@ public class Main {
 
             if (example == null) example = Examples::getCornellBoxSmoke;
             if (path == null) path = Path.of("scene-" + System.currentTimeMillis() + ".png");
-            return new Config(example.apply(height), path, preview, iterative, parallel, samples, depth);
+            return new Config(example.apply(height), path, preview, iterative, parallel, samples, spectralSamples, depth);
         }
 
         private static @NotNull RuntimeException fail(@NotNull String message) {

src/main/java/eu/jonahbauer/raytracing/math/Ray.java

@@ -1,6 +1,7 @@
 package eu.jonahbauer.raytracing.math;
 
 import eu.jonahbauer.raytracing.render.spectrum.SampledWavelengths;
+import eu.jonahbauer.raytracing.scene.HitResult;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Objects;
@@ -19,4 +20,16 @@ public record Ray(@NotNull Vec3 origin, @NotNull Vec3 direction, @NotNull Sample
     public @NotNull Vec3 at(double t) {
         return Vec3.fma(t, direction, origin);
     }
+
+    public @NotNull Ray with(@NotNull HitResult hit, @NotNull Vec3 direction) {
+        return new Ray(hit.position(), direction, lambda);
+    }
+
+    public @NotNull Ray with(@NotNull Vec3 origin, @NotNull Vec3 direction) {
+        return new Ray(origin, direction, lambda);
+    }
+
+    public @NotNull Ray with(@NotNull SampledWavelengths lambda) {
+        return new Ray(origin, direction, lambda);
+    }
 }

src/main/java/eu/jonahbauer/raytracing/render/camera/SimpleCamera.java

@@ -2,7 +2,6 @@ package eu.jonahbauer.raytracing.render.camera;
 
 import eu.jonahbauer.raytracing.math.Ray;
 import eu.jonahbauer.raytracing.math.Vec3;
-import eu.jonahbauer.raytracing.render.spectrum.SampledWavelengths;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -94,7 +93,7 @@ public final class SimpleCamera implements Camera {
 
         var origin = getRayOrigin(random);
         var target = getRayTarget(x, y, i, j, n, random);
-        return new Ray(origin, target.minus(origin), SampledWavelengths.uniform(random.nextDouble()));
+        return new Ray(origin, target.minus(origin));
     }
 
     /**

src/main/java/eu/jonahbauer/raytracing/render/material/DielectricMaterial.java

@@ -45,7 +45,7 @@ public record DielectricMaterial(@NotNull RefractiveIndex ri, @NotNull Texture t
                 .orElseGet(() -> Vec3.reflect(ray.direction(), hit.normal()));
 
         var attenuation = texture.get(hit);
-        return Optional.of(new SpecularScatterResult(attenuation, new Ray(hit.position(), newDirection, ray.lambda())));
+        return Optional.of(new SpecularScatterResult(attenuation, ray.with(hit, newDirection)));
     }
 
     private double reflectance(double cos, double ri) {

src/main/java/eu/jonahbauer/raytracing/render/material/DirectionalMaterial.java

@@ -41,7 +41,7 @@ public final class DirectionalMaterial implements Material {
             if (back != null) return back.scatter(ray, hit, random);
         }
         // let the ray pass through without obstruction
-        return Optional.of(new SpecularScatterResult(Spectra.WHITE, new Ray(ray.at(hit.t()), ray.direction(), ray.lambda())));
+        return Optional.of(new SpecularScatterResult(Spectra.WHITE, ray.with(hit, ray.direction())));
     }
 
     @Override

src/main/java/eu/jonahbauer/raytracing/render/material/MetallicMaterial.java

@@ -28,6 +28,6 @@ public record MetallicMaterial(@NotNull Texture texture, double fuzz) implements
             newDirection = Vec3.fma(fuzz, Vec3.random(random), newDirection.unit());
         }
         var attenuation = texture.get(hit);
-        return Optional.of(new SpecularScatterResult(attenuation, new Ray(hit.position(), newDirection, ray.lambda())));
+        return Optional.of(new SpecularScatterResult(attenuation, ray.with(hit, newDirection)));
     }
 }

src/main/java/eu/jonahbauer/raytracing/render/renderer/SimpleRenderer.java

@@ -7,6 +7,7 @@ import eu.jonahbauer.raytracing.render.renderer.pdf.MixtureProbabilityDensityFun
 import eu.jonahbauer.raytracing.render.spectrum.SampledSpectrum;
 import eu.jonahbauer.raytracing.render.camera.Camera;
 import eu.jonahbauer.raytracing.render.canvas.Canvas;
+import eu.jonahbauer.raytracing.render.spectrum.SampledWavelengths;
 import eu.jonahbauer.raytracing.scene.Scene;
 import org.jetbrains.annotations.NotNull;
 
@@ -20,7 +21,10 @@ import static eu.jonahbauer.raytracing.Main.DEBUG;
 public final class SimpleRenderer implements Renderer {
     private final int sqrtSamplesPerPixel;
     private final int maxDepth;
-    private final double gamma;
+
+    private final int spectralSamples;
+    private final SampledSpectrum black;
+    private final SampledSpectrum white;
 
     private final boolean parallel;
     private final boolean iterative;
@@ -36,7 +40,10 @@ public final class SimpleRenderer implements Renderer {
     private SimpleRenderer(@NotNull Builder builder) {
         this.sqrtSamplesPerPixel = (int) Math.sqrt(builder.samplesPerPixel);
         this.maxDepth = builder.maxDepth;
-        this.gamma = builder.gamma;
+
+        this.spectralSamples = builder.spectralSamples;
+        this.black = new SampledSpectrum(spectralSamples, 0);
+        this.white = new SampledSpectrum(spectralSamples, 1);
 
         this.parallel = builder.parallel;
         this.iterative = builder.iterative;
@@ -96,7 +103,8 @@ public final class SimpleRenderer implements Renderer {
                 int i = 0;
                 for (int sj = 0; sj < sqrtSamplesPerPixel; sj++) {
                     for (int si = 0; si < sqrtSamplesPerPixel; si++) {
-                        var ray = camera.cast(x, y, si, sj, sqrtSamplesPerPixel, random);
+                        var lambda = SampledWavelengths.uniform(random.nextDouble(), spectralSamples);
+                        var ray = camera.cast(x, y, si, sj, sqrtSamplesPerPixel, random).with(lambda);
                         if (DEBUG) {
                             System.out.println("Casting ray " + ray + " through pixel (" + x + "," + y + ") at subpixel (" + si + "," + sj + ")...");
                         }
@@ -116,11 +124,11 @@ public final class SimpleRenderer implements Renderer {
     }
 
     private @NotNull SampledSpectrum getColor0(@NotNull Scene scene, @NotNull Ray ray, int depth, @NotNull RandomGenerator random) {
-        var color = SampledSpectrum.BLACK;
+        var color = black;
-        var attenuation = SampledSpectrum.WHITE;
+        var attenuation = white;
 
         while (depth-- > 0) {
-            var optional = scene.hit(ray);
+            var optional = scene.hit(ray, random);
             if (optional.isEmpty()) {
                 var background = scene.getBackgroundColor(ray);
                 color = SampledSpectrum.fma(attenuation, background, color);
@@ -136,7 +144,7 @@ public final class SimpleRenderer implements Renderer {
             }
             var material = hit.material();
             var emitted = material.emitted(hit).sample(ray.lambda());
-            if (DEBUG && !SampledSpectrum.BLACK.equals(emitted)) {
+            if (DEBUG && !black.equals(emitted)) {
                 System.out.println("  Emitted: " + emitted);
             }
 
@@ -213,7 +221,7 @@ public final class SimpleRenderer implements Renderer {
     public static class Builder {
         private int samplesPerPixel = 100;
         private int maxDepth = 10;
-        private double gamma = 2.0;
+        private int spectralSamples = 4;
         private boolean parallel = true;
         private boolean iterative = false;
 
@@ -229,9 +237,9 @@ public final class SimpleRenderer implements Renderer {
             return this;
         }
 
-        public @NotNull Builder withGamma(double gamma) {
+        public @NotNull Builder withSpectralSamples(int samples) {
-            if (gamma <= 0 || !Double.isFinite(gamma)) throw new IllegalArgumentException("gamma must be positive");
+            if (samples <= 0) throw new IllegalArgumentException("samples must be positive");
-            this.gamma = gamma;
+            this.spectralSamples = samples;
             return this;
         }
 

src/main/java/eu/jonahbauer/raytracing/render/spectrum/SampledSpectrum.java

@@ -10,16 +10,6 @@ import java.util.Arrays;
 
 // TODO use Vector API to parallelize operations
 public final class SampledSpectrum implements IVec<SampledSpectrum> {
-    public static final SampledSpectrum BLACK;
-    public static final SampledSpectrum WHITE;
-
-    static {
-        BLACK = new SampledSpectrum(new double[SampledWavelengths.SAMPLES]);
-        var one = new double[SampledWavelengths.SAMPLES];
-        Arrays.fill(one, 1);
-        WHITE = new SampledSpectrum(one);
-    }
-
     private final double @NotNull[] values;
 
     public SampledSpectrum(@NotNull SampledWavelengths lambdas, @NotNull Spectrum spectrum) {
@@ -30,6 +20,12 @@ public final class SampledSpectrum implements IVec<SampledSpectrum> {
         this.values = values;
     }
 
+    public SampledSpectrum(int count, double value) {
+        var values = new double[count];
+        Arrays.fill(values, value);
+        this.values = values;
+    }
+
     private SampledSpectrum(double @NotNull[] values) {
         this.values = values;
     }

src/main/java/eu/jonahbauer/raytracing/render/spectrum/SampledWavelengths.java

@@ -10,32 +10,31 @@ import java.util.Arrays;
  * A set of sampled wavelength that can be tracked together.
  */
 public final class SampledWavelengths {
-    public static final int SAMPLES = 4;
     public static final SampledWavelengths EMPTY = new SampledWavelengths(new double[0], new double[0]);
 
     private final double @NotNull[] lambdas;
     private final double @NotNull[] pdf;
 
-    public static @NotNull SampledWavelengths uniform(double rng) {
+    public static @NotNull SampledWavelengths uniform(double rng, int count) {
-        return uniform(rng, Spectrum.LAMBDA_MIN, Spectrum.LAMBDA_MAX);
+        return uniform(rng, count, Spectrum.LAMBDA_MIN, Spectrum.LAMBDA_MAX);
     }
 
-    public static @NotNull SampledWavelengths uniform(double rng, double min, double max) {
+    public static @NotNull SampledWavelengths uniform(double rng, int count, double min, double max) {
-        var lambdas = new double[SAMPLES];
+        var lambdas = new double[count];
 
         // choose first sample at random
         lambdas[0] = (1 - rng) * min + rng * max;
 
         // choose next samples in equal intervals, wrapping if necessary
-        var delta = (max - min) / SAMPLES;
+        var delta = (max - min) / count;
-        for (int i = 1; i < SAMPLES; i++) {
+        for (int i = 1; i < count; i++) {
             lambdas[i] = lambdas[i - 1] + delta;
             if (lambdas[i] > max) {
                 lambdas[i] = min + (lambdas[i] - max);
             }
         }
 
-        var pdf = new double[SAMPLES];
+        var pdf = new double[count];
         Arrays.fill(pdf, 1 / (max - min));
         return new SampledWavelengths(lambdas, pdf);
     }

src/main/java/eu/jonahbauer/raytracing/scene/Hittable.java

@@ -9,15 +9,16 @@ import eu.jonahbauer.raytracing.scene.transform.Translate;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Optional;
+import java.util.random.RandomGenerator;
 
 public interface Hittable {
     @NotNull Range FORWARD = new Range(0.001, Double.POSITIVE_INFINITY);
 
     /**
-     * @see #hit(Ray, Range)
+     * @see #hit(Ray, Range, RandomGenerator)
      */
-    default @NotNull Optional<HitResult> hit(@NotNull Ray ray) {
+    default @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull RandomGenerator random) {
-        return hit(ray, FORWARD);
+        return hit(ray, FORWARD, random);
     }
 
     /**
@@ -31,7 +32,7 @@ public interface Hittable {
      * @return the result of the hit test, containing (among others) the value {@code t} such that {@code ray.at(t)} is
      *         a point on {@code this} hittable
      */
-    @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range);
+    @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range, @NotNull RandomGenerator random);
 
     /**
      * {@return the axis-aligned bounding box of this hittable}

src/main/java/eu/jonahbauer/raytracing/scene/Scene.java

@@ -12,6 +12,7 @@ import org.jetbrains.annotations.Nullable;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
+import java.util.random.RandomGenerator;
 
 public final class Scene extends HittableCollection {
     private final @NotNull HittableCollection objects;
@@ -42,8 +43,8 @@ public final class Scene extends HittableCollection {
     }
 
     @Override
-    public void hit(@NotNull Ray ray, @NotNull State state) {
+    public void hit(@NotNull Ray ray, @NotNull State state, @NotNull RandomGenerator random) {
-        objects.hit(ray, state);
+        objects.hit(ray, state, random);
     }
 
     @Override

src/main/java/eu/jonahbauer/raytracing/scene/hittable2d/Hittable2D.java

@@ -7,9 +7,11 @@ import eu.jonahbauer.raytracing.render.material.Material;
 import eu.jonahbauer.raytracing.scene.HitResult;
 import eu.jonahbauer.raytracing.scene.Hittable;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.Objects;
 import java.util.Optional;
+import java.util.random.RandomGenerator;
 
 public abstract class Hittable2D implements Hittable {
     protected final @NotNull Vec3 origin;
@@ -36,7 +38,7 @@ public abstract class Hittable2D implements Hittable {
     }
 
     @Override
-    public @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range) {
+    public @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range, @Nullable RandomGenerator random) {
         var denominator = ray.direction().dot(normal);
         if (Math.abs(denominator) < 1e-8) return Optional.empty(); // parallel
 

src/main/java/eu/jonahbauer/raytracing/scene/hittable3d/Box.java

@@ -48,7 +48,7 @@ public final class Box implements Hittable, Target {
     }
 
     @Override
-    public @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range) {
+    public @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range, @Nullable RandomGenerator random) {
         // based on AABB#hit with additional detection of the side hit
         var origin = ray.origin();
         var direction = ray.direction();
@@ -103,13 +103,13 @@ public final class Box implements Hittable, Target {
             t = tmin;
             side = entry;
             frontFace = true;
-            material = materials[side.ordinal()];
+            material = materials[entry.ordinal()];
             normal = side.normal;
         } else if (range.surrounds(tmax) && materials[exit.ordinal()] != null) {
             t = tmax;
             side = exit;
             frontFace = false;
-            material = materials[side.ordinal()];
+            material = materials[exit.ordinal()];
             normal = side.normal.neg();
         } else {
             return Optional.empty();
@@ -130,7 +130,7 @@ public final class Box implements Hittable, Target {
     @Override
     public double getProbabilityDensity(@NotNull Vec3 origin, @NotNull Vec3 direction) {
         if (contains(origin)) return 1 / (4 * Math.PI);
-        if (hit(new Ray(origin, direction)).isEmpty()) return 0;
+        if (hit(new Ray(origin, direction), null).isEmpty()) return 0;
 
         var solidAngle = 0d;
         for (var s : Side.values()) {

src/main/java/eu/jonahbauer/raytracing/scene/hittable3d/ConstantMedium.java

@@ -10,15 +10,16 @@ import eu.jonahbauer.raytracing.scene.Hittable;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Optional;
+import java.util.random.RandomGenerator;
 
 public record ConstantMedium(@NotNull Hittable boundary, double density, @NotNull IsotropicMaterial material) implements Hittable {
 
     @Override
-    public @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range) {
+    public @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range, @NotNull RandomGenerator random) {
-        var hit1 = boundary.hit(ray, Range.UNIVERSE);
+        var hit1 = boundary.hit(ray, Range.UNIVERSE, random);
         if (hit1.isEmpty()) return Optional.empty();
 
-        var hit2 = boundary.hit(ray, new Range(hit1.get().t() + 0.0001, Double.POSITIVE_INFINITY));
+        var hit2 = boundary.hit(ray, new Range(hit1.get().t() + 0.0001, Double.POSITIVE_INFINITY), random);
         if (hit2.isEmpty()) return Optional.empty();
 
         var tmin = Math.max(range.min(), hit1.get().t());
@@ -28,7 +29,7 @@ public record ConstantMedium(@NotNull Hittable boundary, double density, @NotNul
 
         var length = ray.direction().length();
         var distance = length * (tmax - tmin);
-        var hitDistance = - Math.log(Math.random()) / density;
+        var hitDistance = - Math.log(random.nextDouble()) / density;
         if (hitDistance > distance) return Optional.empty();
 
         var t = tmin + hitDistance / length;

src/main/java/eu/jonahbauer/raytracing/scene/hittable3d/Sphere.java

@@ -9,6 +9,7 @@ import eu.jonahbauer.raytracing.scene.HitResult;
 import eu.jonahbauer.raytracing.scene.Hittable;
 import eu.jonahbauer.raytracing.scene.Target;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.Objects;
 import java.util.Optional;
@@ -40,7 +41,7 @@ public final class Sphere implements Hittable, Target {
     }
 
     @Override
-    public @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range) {
+    public @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range, @Nullable RandomGenerator random) {
         var t = hit0(ray, range);
         if (Double.isNaN(t)) return Optional.empty();
 

src/main/java/eu/jonahbauer/raytracing/scene/transform/Transform.java

@@ -2,10 +2,8 @@ package eu.jonahbauer.raytracing.scene.transform;
 
 import eu.jonahbauer.raytracing.math.Range;
 import eu.jonahbauer.raytracing.math.Ray;
-import eu.jonahbauer.raytracing.math.Vec3;
 import eu.jonahbauer.raytracing.scene.HitResult;
 import eu.jonahbauer.raytracing.scene.Hittable;
-import eu.jonahbauer.raytracing.scene.Target;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Objects;
@@ -24,7 +22,7 @@ public abstract class Transform implements Hittable {
     protected abstract @NotNull HitResult transform(@NotNull HitResult result);
 
     @Override
-    public final @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range) {
+    public final @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range, @NotNull RandomGenerator random) {
-        return object.hit(transform(ray), range).map(this::transform);
+        return object.hit(transform(ray), range, random).map(this::transform);
     }
 }

src/main/java/eu/jonahbauer/raytracing/scene/util/HittableBinaryTree.java

@@ -8,6 +8,7 @@ import org.jetbrains.annotations.Nullable;
 
 import java.util.Comparator;
 import java.util.List;
+import java.util.random.RandomGenerator;
 
 public final class HittableBinaryTree extends HittableCollection {
     private final @Nullable Hittable left;
@@ -46,17 +47,17 @@ public final class HittableBinaryTree extends HittableCollection {
     }
 
     @Override
-    public void hit(@NotNull Ray ray, @NotNull State state) {
+    public void hit(@NotNull Ray ray, @NotNull State state, @NotNull RandomGenerator random) {
         if (!bbox.hit(ray, state.getRange())) return;
         if (left instanceof HittableCollection coll) {
-            coll.hit(ray, state);
+            coll.hit(ray, state, random);
         } else if (left != null) {
-            hit(state, ray, left);
+            hit(state, ray, left, random);
         }
         if (right instanceof HittableCollection coll) {
-            coll.hit(ray, state);
+            coll.hit(ray, state, random);
         } else if (right != null) {
-            hit(state, ray, right);
+            hit(state, ray, right, random);
         }
     }
 

src/main/java/eu/jonahbauer/raytracing/scene/util/HittableCollection.java

@@ -8,20 +8,21 @@ import org.jetbrains.annotations.NotNull;
 
 import java.util.Objects;
 import java.util.Optional;
+import java.util.random.RandomGenerator;
 
 public abstract class HittableCollection implements Hittable {
 
     @Override
-    public final @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range) {
+    public final @NotNull Optional<HitResult> hit(@NotNull Ray ray, @NotNull Range range, @NotNull RandomGenerator random) {
         var state = new State(range);
-        hit(ray, state);
+        hit(ray, state, random);
         return state.getResult();
     }
 
-    public abstract void hit(@NotNull Ray ray, @NotNull State state);
+    public abstract void hit(@NotNull Ray ray, @NotNull State state, @NotNull RandomGenerator random);
 
-    protected static boolean hit(@NotNull State state, @NotNull Ray ray, @NotNull Hittable object) {
+    protected static boolean hit(@NotNull State state, @NotNull Ray ray, @NotNull Hittable object, @NotNull RandomGenerator random) {
-        var r = object.hit(ray, state.range);
+        var r = object.hit(ray, state.range, random);
         if (r.isPresent()) {
             if (state.range.surrounds(r.get().t())){
                 state.result = r.get();

src/main/java/eu/jonahbauer/raytracing/scene/util/HittableList.java

@@ -7,6 +7,7 @@ import org.jetbrains.annotations.NotNull;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.random.RandomGenerator;
 
 public final class HittableList extends HittableCollection {
     private final @NotNull List<Hittable> objects;
@@ -22,8 +23,8 @@ public final class HittableList extends HittableCollection {
     }
 
     @Override
-    public void hit(@NotNull Ray ray, @NotNull State state) {
+    public void hit(@NotNull Ray ray, @NotNull State state, @NotNull RandomGenerator random) {
-        objects.forEach(object -> hit(state, ray, object));
+        objects.forEach(object -> hit(state, ray, object, random));
     }
 
     @Override