Implement multiple cloud layers

chunky/src/java/se/llbit/chunky/renderer/scene/CuboidFogVolume.java

@@ -18,7 +18,7 @@ public class CuboidFogVolume extends FogVolume {
   private AABB aabb;
 
   @Override
-  public boolean intersect(Ray ray, Scene scene, Random random) {
+  public boolean intersect(Scene scene, Ray ray, Random random) {
     double distance;
     double fogPenetrated = -FastMath.log(1 - random.nextDouble());
     double fogDistance = fogPenetrated / density;

chunky/src/java/se/llbit/chunky/renderer/scene/ExponentialFogVolume.java

@@ -25,7 +25,7 @@ public ExponentialFogVolume(Vector3 color, double density) {
   }
 
   @Override
-  public boolean intersect(Ray ray, Scene scene, Random random) {
+  public boolean intersect(Scene scene, Ray ray, Random random) {
     // Amount of fog the ray should pass through before being scattered
     // Sampled from an exponential distribution
     double fogPenetrated = -FastMath.log(1 - random.nextDouble());

chunky/src/java/se/llbit/chunky/renderer/scene/Fog.java

@@ -230,6 +230,17 @@ private double sampleLayeredScatterOffset(Random random, double y1, double y2, d
     return (offsetY - y1) / clampDy(dy);
   }
 
+  public boolean particleFogIntersection(Scene scene, Ray ray, Random random) {
+    if (random == null) {
+      return false;
+    }
+    boolean hit = false;
+    for (FogVolume v : volumes) {
+      hit |= v.intersect(scene, ray, random);
+    }
+    return hit;
+  }
+
   @Override public JsonObject toJson() {
     JsonObject fogObj = new JsonObject();
     fogObj.add("mode", mode.name());
@@ -249,11 +260,7 @@ private double sampleLayeredScatterOffset(Random random, double y1, double y2, d
       jsonVolumes.add(volume.toJson());
     }
     fogObj.add("volumes", jsonVolumes);
-    JsonObject colorObj = new JsonObject();
-    colorObj.add("red", fogColor.x);
-    colorObj.add("green", fogColor.y);
-    colorObj.add("blue", fogColor.z);
-    fogObj.add("color", colorObj);
+    fogObj.add("color", ColorUtil.rgbToJson(fogColor));
     fogObj.add("fastFog", fastFog);
     return fogObj;
   }
@@ -276,10 +283,7 @@ public void importFromJson(JsonObject json, Scene scene) {
       fogVolume.importFromJson(jsonVolumeObject);
       addVolume(fogVolume);
     }
-    JsonObject colorObj = json.get("color").object();
-    fogColor.x = colorObj.get("red").doubleValue(fogColor.x);
-    fogColor.y = colorObj.get("green").doubleValue(fogColor.y);
-    fogColor.z = colorObj.get("blue").doubleValue(fogColor.z);
+    fogColor.set(ColorUtil.jsonToRGB(json.get("color").object()));
     fastFog = json.get("fastFog").boolValue(fastFog);
   }
 
@@ -289,10 +293,7 @@ public void importFromLegacy(JsonObject json) {
     skyFogDensity = json.get("skyFogDensity").doubleValue(skyFogDensity);
     layers.clear();
     volumes.clear();
-    JsonObject colorObj = json.get("fogColor").object();
-    fogColor.x = colorObj.get("red").doubleValue(fogColor.x);
-    fogColor.y = colorObj.get("green").doubleValue(fogColor.y);
-    fogColor.z = colorObj.get("blue").doubleValue(fogColor.z);
+    fogColor.set(ColorUtil.jsonToRGB(json.get("fogColor").asObject()));
     fastFog = json.get("fastFog").boolValue(fastFog);
   }
 

chunky/src/java/se/llbit/chunky/renderer/scene/FogVolume.java

@@ -1,9 +1,10 @@
 package se.llbit.chunky.renderer.scene;
 
-import org.apache.commons.math3.util.FastMath;
 import se.llbit.chunky.world.Material;
+import se.llbit.chunky.world.VolumeMaterial;
 import se.llbit.chunky.world.material.ParticleFogMaterial;
 import se.llbit.json.JsonObject;
+import se.llbit.math.ColorUtil;
 import se.llbit.math.Ray;
 import se.llbit.math.Vector3;
 import se.llbit.util.JsonSerializable;
@@ -14,27 +15,12 @@ public abstract class FogVolume implements JsonSerializable {
   protected FogVolumeType type;
   protected Vector3 color;
   protected double density;
-  protected Material material = new ParticleFogMaterial();
+  protected VolumeMaterial material = new ParticleFogMaterial();
 
-  public abstract boolean intersect(Ray ray, Scene scene, Random random);
+  public abstract boolean intersect(Scene scene, Ray ray, Random random);
 
   public void setRandomNormal(Ray ray, Random random) {
-    Vector3 a1 = new Vector3();
-    a1.cross(ray.d, new Vector3(0, 1, 0));
-    a1.normalize();
-    Vector3 a2 = new Vector3();
-    a2.cross(ray.d, a1);
-    // get random point on unit disk
-    double x1 = random.nextDouble();
-    double x2 = random.nextDouble();
-    double r = FastMath.sqrt(x1);
-    double theta = 2 * Math.PI * x2;
-    double t1 = r * FastMath.cos(theta);
-    double t2 = r * FastMath.sin(theta);
-    a1.scale(t1);
-    a1.scaleAdd(t2, a2);
-    a1.scaleAdd(-Math.sqrt(1 - a1.lengthSquared()), ray.d);
-    ray.setNormal(a1);
+    material.setRandomSphericalNormal(ray, random);
   }
 
   public void setRayMaterialAndColor(Ray ray) {
@@ -88,11 +74,7 @@ public FogVolumeType getType() {
   public JsonObject toJson() {
     JsonObject properties = volumeSpecificPropertiesToJson();
     properties.add("type", type.name());
-    JsonObject colorObj = new JsonObject();
-    colorObj.add("red", color.x);
-    colorObj.add("green", color.y);
-    colorObj.add("blue", color.z);
-    properties.add("color", colorObj);
+    properties.add("color", ColorUtil.rgbToJson(color));
     properties.add("density", density);
     properties.add("materialProperties", materialPropertiesToJson());
     return properties;
@@ -108,10 +90,7 @@ protected JsonObject materialPropertiesToJson() {
   protected abstract void importVolumeSpecificProperties(JsonObject jsonObject);
 
   public void importFromJson(JsonObject json) {
-    JsonObject colorObj = json.get("color").object();
-    color.x = colorObj.get("red").doubleValue(color.x);
-    color.y = colorObj.get("green").doubleValue(color.y);
-    color.z = colorObj.get("blue").doubleValue(color.z);
+    color.set(ColorUtil.jsonToRGB(json.get("color").asObject()));
     density = json.get("density").doubleValue(Scene.DEFAULT_FOG_DENSITY);
     JsonObject materialProperties = json.get("materialProperties").object();
     importMaterialProperties(materialProperties);

chunky/src/java/se/llbit/chunky/renderer/scene/IntersectionConfig.java

@@ -14,6 +14,6 @@ public IntersectionConfig(boolean cloudIntersect, boolean fogIntersect, boolean
   }
 
   public static IntersectionConfig defaultIntersect(Scene scene, boolean isRenderPreview) {
-    return new IntersectionConfig(scene.sky().cloudsEnabled(), !isRenderPreview || scene.getPreviewParticleFog(), scene.isWaterPlaneEnabled(), true);
+    return new IntersectionConfig(true, !isRenderPreview || scene.getPreviewParticleFog(), scene.isWaterPlaneEnabled(), true);
   }
 }

chunky/src/java/se/llbit/chunky/renderer/scene/LayerFogVolume.java

@@ -24,7 +24,7 @@ public LayerFogVolume(Vector3 color, double density) {
   }
 
   @Override
-  public boolean intersect(Ray ray, Scene scene, Random random) {
+  public boolean intersect(Scene scene, Ray ray, Random random) {
     // Amount of fog the ray should pass through before being scattered
     // Sampled from an exponential distribution
     double fogPenetrated = -Math.log(1 - random.nextDouble());

chunky/src/java/se/llbit/chunky/renderer/scene/PreviewRayTracer.java

@@ -119,22 +119,15 @@ public static boolean nextIntersection(Scene scene, Ray ray, Random random, Inte
   }
 
   public static boolean nextIntersection(Scene scene, Ray ray) {
-    return nextIntersection(scene, ray, null, new IntersectionConfig((scene.sky.cloudsEnabled() && !scene.sky.getVolumetricClouds()), false, scene.waterPlaneEnabled, true));
+    return nextIntersection(scene, ray, null, new IntersectionConfig(true, false, scene.waterPlaneEnabled, true));
   }
 
   private static boolean cloudIntersection(Scene scene, Ray ray, Random random) {
     return scene.sky.cloudIntersection(scene, ray, random);
   }
 
   private static boolean fogIntersection(Scene scene, Ray ray, Random random) {
-    if (random == null) {
-      return false;
-    }
-    boolean hit = false;
-    for(FogVolume v : scene.fog.getFogVolumes()) {
-      hit |= v.intersect(ray, scene, random);
-    }
-    return hit;
+    return scene.fog.particleFogIntersection(scene, ray, random);
   }
 
   private static boolean waterPlaneIntersection(Scene scene, Ray ray) {

chunky/src/java/se/llbit/chunky/renderer/scene/Scene.java

@@ -1686,7 +1686,7 @@ public boolean traceTarget(Ray ray) {
     ray.o.y -= origin.y;
     ray.o.z -= origin.z;
     while (PreviewRayTracer.nextIntersection(this, ray, null,
-      new IntersectionConfig((sky.cloudsEnabled() && !sky.getVolumetricClouds()),
+      new IntersectionConfig(true,
         false, waterPlaneEnabled, true))) {
       if (ray.getCurrentMaterial() != Air.INSTANCE) {
         return true;
@@ -2658,11 +2658,7 @@ public void setUseCustomWaterColor(boolean value) {
     json.add("waterVisibility", waterVisibility);
     json.add("useCustomWaterColor", useCustomWaterColor);
     if (useCustomWaterColor) {
-      JsonObject colorObj = new JsonObject();
-      colorObj.add("red", waterColor.x);
-      colorObj.add("green", waterColor.y);
-      colorObj.add("blue", waterColor.z);
-      json.add("waterColor", colorObj);
+      json.add("waterColor", ColorUtil.rgbToJson(waterColor));
     }
     waterShading.save(json);
     json.add("fog", fog.toJson());
@@ -2940,10 +2936,7 @@ public synchronized void importFromJson(JsonObject json) {
     waterVisibility = json.get("waterVisibility").doubleValue(waterVisibility);
     useCustomWaterColor = json.get("useCustomWaterColor").boolValue(useCustomWaterColor);
     if (useCustomWaterColor) {
-      JsonObject colorObj = json.get("waterColor").object();
-      waterColor.x = colorObj.get("red").doubleValue(waterColor.x);
-      waterColor.y = colorObj.get("green").doubleValue(waterColor.y);
-      waterColor.z = colorObj.get("blue").doubleValue(waterColor.z);
+      waterColor.set(ColorUtil.jsonToRGB(json.get("waterColor").asObject()));
     }
     String waterShader = json.get("waterShader").stringValue("SIMPLEX");
     if(waterShader.equals("LEGACY"))