Data-driven sublevel collisions with fluids

common/src/main/java/dev/ryanhcode/sable/physics/chunk/VoxelNeighborhoodState.java

@@ -1,14 +1,14 @@
 package dev.ryanhcode.sable.physics.chunk;
 
 import dev.ryanhcode.sable.api.block.BlockWithSubLevelCollisionCallback;
+import dev.ryanhcode.sable.physics.config.block_properties.PhysicsBlockPropertyHelper;
 import dev.ryanhcode.sable.util.LevelAccelerator;
 import it.unimi.dsi.fastutil.ints.Int2BooleanOpenHashMap;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.world.level.BlockGetter;
 import net.minecraft.world.level.ChunkPos;
-import net.minecraft.world.level.block.KelpBlock;
-import net.minecraft.world.level.block.KelpPlantBlock;
+import net.minecraft.world.level.block.*;
 import net.minecraft.world.level.block.piston.MovingPistonBlock;
 import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.level.chunk.LevelChunk;
@@ -70,15 +70,11 @@ public static boolean isFullBlock(final BlockGetter blockGetter, final BlockPos
         return IS_FULL_BLOCK.apply(blockGetter, state);
     }
 
-    public static boolean isLiquid(final BlockState state) {
-        return state.liquid() || state.getBlock() instanceof KelpPlantBlock || state.getBlock() instanceof KelpBlock;
-    }
-
     public static VoxelNeighborhoodState getState(final LevelAccelerator level, final BlockPos pos, @Nullable final LevelChunk chunk) {
         final ChunkPos initialPos = new ChunkPos(pos);
         final BlockState state = chunk != null ? level.getBlockState(chunk, pos) : level.getBlockState(pos);
 
-        if (isLiquid(state) || BlockWithSubLevelCollisionCallback.hasCallback(state))
+        if (PhysicsBlockPropertyHelper.getFluidViscosity(state) > 0 || BlockWithSubLevelCollisionCallback.hasCallback(state))
             return CORNER;
 
         if (!isSolid(level, pos, state)) {

common/src/main/java/dev/ryanhcode/sable/physics/config/block_properties/PhysicsBlockPropertyHelper.java

@@ -7,6 +7,7 @@
 import net.minecraft.core.BlockPos;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.level.BlockGetter;
+import net.minecraft.world.level.block.BubbleColumnBlock;
 import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.phys.Vec3;
 import org.jetbrains.annotations.Nullable;
@@ -102,4 +103,36 @@ public static FloatingBlockMaterial getFloatingMaterial(final BlockState state)
         return FloatingBlockMaterialDataHandler.allMaterials.get(location);
     }
 
+    /**
+     * Gets the buoyancy of a fluid block
+     *
+     * @param state The state of the block
+     * @return The buoyancy of the fluid
+     */
+    public static double getFluidBuoyancy(final BlockState state) {
+        if (state.getBlock() instanceof BubbleColumnBlock) {
+            if (state.getValue(BubbleColumnBlock.DRAG_DOWN)) {
+                return -1.0;
+            } else {
+                return 3.0;
+            }
+        }
+
+        return ((BlockStateExtension) state).sable$getProperty(PhysicsBlockPropertyTypes.BUOYANCY.get());
+    }
+
+    /**
+     * Gets the viscosity of a fluid block
+     *
+     * @param state The state of the block
+     * @return The viscosity of the fluid
+     */
+    public static double getFluidViscosity(final BlockState state) {
+        if (state.getBlock() instanceof BubbleColumnBlock) {
+            return 1.0;
+        }
+
+        return ((BlockStateExtension) state).sable$getProperty(PhysicsBlockPropertyTypes.VISCOSITY.get());
+    }
+
 }

common/src/main/java/dev/ryanhcode/sable/physics/config/block_properties/PhysicsBlockPropertyTypes.java

@@ -54,6 +54,14 @@ public class PhysicsBlockPropertyTypes {
      * The scale / multiplier of the effects caused by the floating material for this block
      */
     public static final RegistryObject<PhysicsBlockPropertyType<Double>> FLOATING_SCALE = register(Sable.sablePath("floating_scale"), Codec.DOUBLE, 1.0);
+    /**
+     * The buoyancy of a fluid
+     */
+    public static final RegistryObject<PhysicsBlockPropertyType<Double>> BUOYANCY = register(Sable.sablePath("buoyancy"), Codec.DOUBLE, 0.0);
+    /**
+     * The viscosity of a fluid
+     */
+    public static final RegistryObject<PhysicsBlockPropertyType<Double>> VISCOSITY = register(Sable.sablePath("viscosity"), Codec.DOUBLE, 0.0);
 
     public static void register() {
         // no-op

common/src/main/java/dev/ryanhcode/sable/physics/impl/rapier/Rapier3D.java

@@ -218,17 +218,18 @@ public static synchronized int getID(final ServerLevel level) {
      * Adds a new voxel collider data entry.
      *
      * @param frictionMultiplier the friction multiplier
-     * @param isFluid            if the block should be treated as a fluid
+     * @param buoyancy           if the block is a fluid, its buoyancy
+     * @param viscosity          if the block is a fluid, its viscosity
      * @param contactEvents      if the block has special contact event behavior
      * @return the ID of the new block collider data entry
      */
     @ApiStatus.Internal
-    protected static native int newVoxelCollider(double frictionMultiplier, double volume, double restitution, boolean isFluid, BlockSubLevelCollisionCallback contactEvents);
+    protected static native int newVoxelCollider(double frictionMultiplier, double volume, double restitution, double buoyancy, double viscosity, BlockSubLevelCollisionCallback contactEvents);
 
     /**
      * Adds a new box to a voxel collider data entry.
      *
-     * @param index  the ID of the block physics data entry from {@link Rapier3D#newVoxelCollider(double, double, double, boolean, BlockSubLevelCollisionCallback)}}
+     * @param index  the ID of the block physics data entry from {@link Rapier3D#newVoxelCollider(double, double, double, double, double, BlockSubLevelCollisionCallback)}}
      * @param bounds a 6-long double array, formatted [minX, minY, minZ, maxX, maxY, maxZ]
      */
     @ApiStatus.Internal
@@ -237,7 +238,7 @@ public static synchronized int getID(final ServerLevel level) {
     /**
      * Clears all boxes from a voxel collider data entry.
      *
-     * @param index the ID of the block physics data entry from {@link Rapier3D#newVoxelCollider(double, double, double, boolean, BlockSubLevelCollisionCallback)}}
+     * @param index the ID of the block physics data entry from {@link Rapier3D#newVoxelCollider(double, double, double, double, double, BlockSubLevelCollisionCallback)}}
      */
     @ApiStatus.Internal
     public static native void clearVoxelColliderBoxes(int index);
@@ -254,13 +255,14 @@ public static synchronized int getID(final ServerLevel level) {
      * Allocates a new block physics data entry
      *
      * @param frictionMultiplier the friction multiplier
-     * @param isFluid            if the block should be treated as a fluid
+     * @param buoyancy           if the block is a fluid, its buoyancy
+     * @param viscosity          if the block is a fluid, its viscosity
      * @param contactEvents      if the block has special contact event behavior
      * @return the handle of the new block physics data entry
      */
     @ApiStatus.Internal
-    public static RapierVoxelColliderData createVoxelColliderEntry(final double frictionMultiplier, final double volume, final double restitution, final boolean isFluid, final BlockSubLevelCollisionCallback contactEvents) {
-        return new RapierVoxelColliderData(Rapier3D.newVoxelCollider(frictionMultiplier, volume, restitution, isFluid, contactEvents));
+    public static RapierVoxelColliderData createVoxelColliderEntry(final double frictionMultiplier, final double volume, final double restitution, final double buoyancy, final double viscosity, final BlockSubLevelCollisionCallback contactEvents) {
+        return new RapierVoxelColliderData(Rapier3D.newVoxelCollider(frictionMultiplier, volume, restitution, buoyancy, viscosity, contactEvents));
     }
 
     /**

common/src/main/java/dev/ryanhcode/sable/physics/impl/rapier/collider/RapierVoxelColliderBakery.java

@@ -5,7 +5,6 @@
 import dev.ryanhcode.sable.api.physics.callback.BlockSubLevelCollisionCallback;
 import dev.ryanhcode.sable.api.physics.collider.SableCollisionContext;
 import dev.ryanhcode.sable.companion.math.JOMLConversion;
-import dev.ryanhcode.sable.physics.chunk.VoxelNeighborhoodState;
 import dev.ryanhcode.sable.physics.config.block_properties.PhysicsBlockPropertyHelper;
 import dev.ryanhcode.sable.physics.impl.rapier.Rapier3D;
 import net.minecraft.Util;
@@ -51,15 +50,17 @@ public RapierVoxelColliderBakery(@NotNull final BlockGetter blockGetter) {
      * @return the physics data ID for the block at the given position, or null for empty
      */
     private @NotNull RapierVoxelColliderData buildPhysicsDataForBlock(final BlockState childState) {
-        final boolean liquid = VoxelNeighborhoodState.isLiquid(childState);
 
         final double friction = PhysicsBlockPropertyHelper.getFriction(childState);
         final double volume = PhysicsBlockPropertyHelper.getVolume(childState);
         final double restitution = PhysicsBlockPropertyHelper.getRestitution(childState);
+        final double buoyancy = PhysicsBlockPropertyHelper.getFluidBuoyancy(childState);
+        final double viscosity = PhysicsBlockPropertyHelper.getFluidViscosity(childState);
         final BlockSubLevelCollisionCallback callback = BlockWithSubLevelCollisionCallback.sable$getCallback(childState);
-        final RapierVoxelColliderData entry = Rapier3D.createVoxelColliderEntry(friction, volume, restitution, liquid, callback);
+        final RapierVoxelColliderData entry = Rapier3D.createVoxelColliderEntry(friction, volume, restitution, buoyancy, viscosity, callback);
 
-        if (liquid) {
+
+        if (viscosity > 0) {
             entry.addBox(JOMLConversion.ZERO, new Vector3d(1.0, 1.0, 1.0));
             return entry;
         }

common/src/main/resources/data/sable/physics_block_properties/high_buoyancy_fluid.json

@@ -0,0 +1,7 @@
+{
+  "selector": "#sable:high_buoyancy_fluid",
+
+  "properties": {
+    "sable:buoyancy": 2.0
+  }
+}

common/src/main/resources/data/sable/physics_block_properties/low_buoyancy_fluid.json

@@ -0,0 +1,7 @@
+{
+  "selector": "#sable:low_buoyancy_fluid",
+
+  "properties": {
+    "sable:buoyancy": 1.0
+  }
+}

common/src/main/resources/data/sable/physics_block_properties/runny_fluid.json

@@ -0,0 +1,7 @@
+{
+  "selector": "#sable:runny_fluid",
+
+  "properties": {
+    "sable:viscosity": 1.0
+  }
+}

common/src/main/resources/data/sable/physics_block_properties/viscous_fluid.json

@@ -0,0 +1,7 @@
+{
+  "selector": "#sable:viscous_fluid",
+
+  "properties": {
+    "sable:viscosity": 4.0
+  }
+}

common/src/main/resources/data/sable/tags/block/high_buoyancy_fluid.json

@@ -0,0 +1,7 @@
+{
+  "replace": false,
+  "values": [
+    "minecraft:lava",
+    { "id": "create:honey", "required": false }
+  ]
+}

common/src/main/resources/data/sable/tags/block/low_buoyancy_fluid.json

@@ -0,0 +1,7 @@
+{
+  "replace": false,
+  "values": [
+    "minecraft:water",
+    { "id": "create:chocolate", "required": false }
+  ]
+}

common/src/main/resources/data/sable/tags/block/runny_fluid.json

@@ -0,0 +1,6 @@
+{
+  "replace": false,
+  "values": [
+    "minecraft:water"
+  ]
+}

common/src/main/resources/data/sable/tags/block/viscous_fluid.json

@@ -0,0 +1,8 @@
+{
+  "replace": false,
+  "values": [
+    "minecraft:lava",
+    { "id": "create:chocolate", "required": false },
+    { "id": "create:honey", "required": false }
+  ]
+}

common/src/main/rust/marten/src/level.rs

@@ -83,8 +83,9 @@ pub struct VoxelColliderData {
     /// Formatted [min_x, min_y, min_z, max_x, max_y, max_z]
     pub collision_boxes: Vec<(f32, f32, f32, f32, f32, f32)>,
 
-    /// If this should be treated as a fluid for buoyancy
-    pub is_fluid: bool,
+    /// Non-zero values if this is a fluid
+    pub buoyancy: f32,
+    pub viscosity: f32,
 
     /// The friction multiplier
     pub friction: f32,

common/src/main/rust/rapier/src/buoyancy.rs

@@ -47,7 +47,33 @@ pub fn compute_buoyancy(scene: &mut PhysicsScene) {
         let vels: RigidBodyVelocity<Real> = *body.vels();
 
         let complex = (local_bounds_max - local_bounds_min).sum() < 10;
+        let scene = state.scenes.get_mut(&scene.scene_id).unwrap();
         for (static_pos, dynamic_pos) in pairs.iter() {
+            let fluid_chunk = scene.get_chunk(static_pos.x >> 4, static_pos.y >> 4, static_pos.z >> 4);
+
+            if fluid_chunk.is_none() {
+                continue;
+            }
+
+            let (fluid_block_id, _) = fluid_chunk.unwrap().get_block(
+                static_pos.x & 15,
+                static_pos.y & 15,
+                static_pos.z & 15,
+            );
+
+            if fluid_block_id == 0 {
+                continue;
+            }
+
+            let fluid_voxel_data = &state.voxel_collider_map.get(
+                (fluid_block_id - 1) as usize,
+                Vector3::new(static_pos.x, static_pos.y, static_pos.z),
+            );
+
+            let Some(fluid_data) = fluid_voxel_data else {
+                continue;
+            };
+
             let local_pos = Vector3::<f64>::new(
                 dynamic_pos.x as f64 + 0.5,
                 dynamic_pos.y as f64 + 0.5,
@@ -68,13 +94,13 @@ pub fn compute_buoyancy(scene: &mut PhysicsScene) {
                         local_pos.y + y as Real * 0.25,
                         local_pos.z + z as Real * 0.25,
                     );
-                    do_drag(body, &vels, static_pos, &local_pos, 0.25, 1.0);
+                    do_drag(body, &vels, static_pos, &local_pos, 0.25, 1.0, fluid_data.viscosity);
                 }
             } else {
-                do_drag(body, &vels, static_pos, &local_pos, 0.5, 1.0);
+                do_drag(body, &vels, static_pos, &local_pos, 0.5, 1.0, fluid_data.viscosity);
             }
         }
-        let scene = state.scenes.get_mut(&scene.scene_id).unwrap();
+
         for (static_pos, dynamic_pos) in pairs.iter() {
             let chunk = scene.get_chunk(dynamic_pos.x >> 4, dynamic_pos.y >> 4, dynamic_pos.z >> 4);
 
@@ -102,6 +128,31 @@ pub fn compute_buoyancy(scene: &mut PhysicsScene) {
                 continue;
             };
 
+            let fluid_chunk = scene.get_chunk(static_pos.x >> 4, static_pos.y >> 4, static_pos.z >> 4);
+
+            if fluid_chunk.is_none() {
+                continue;
+            }
+
+            let (fluid_block_id, _) = fluid_chunk.unwrap().get_block(
+                static_pos.x & 15,
+                static_pos.y & 15,
+                static_pos.z & 15,
+            );
+
+            if fluid_block_id == 0 {
+                continue;
+            }
+
+            let fluid_voxel_data = &state.voxel_collider_map.get(
+                (fluid_block_id - 1) as usize,
+                Vector3::new(static_pos.x, static_pos.y, static_pos.z),
+            );
+
+            let Some(fluid_data) = fluid_voxel_data else {
+                continue;
+            };
+
             let local_pos = Vector3::<f64>::new(
                 dynamic_pos.x as f64 + 0.5,
                 dynamic_pos.y as f64 + 0.5,
@@ -129,6 +180,7 @@ pub fn compute_buoyancy(scene: &mut PhysicsScene) {
                         &local_pos,
                         0.25,
                         voxel_collider_data.volume,
+                        fluid_data.buoyancy
                     );
                 }
             } else {
@@ -138,6 +190,7 @@ pub fn compute_buoyancy(scene: &mut PhysicsScene) {
                     &local_pos,
                     0.5,
                     voxel_collider_data.volume,
+                    fluid_data.buoyancy
                 );
             }
         }
@@ -151,6 +204,7 @@ fn do_drag(
     point: &Vector,
     size: Real,
     strength: Real,
+    viscosity: Real
 ) {
     let point = body.position().transform_point(*point);
 
@@ -176,7 +230,7 @@ fn do_drag(
     let volume = overlap.unwrap().volume();
     let velo = vels.velocity_at_point(point, body.mass_properties().world_com);
 
-    body.add_force_at_point(-velo * 1.7 * volume * strength, point, false);
+    body.add_force_at_point(-velo * 1.7 * volume * strength * viscosity, point, false);
 }
 
 fn do_float(
@@ -185,6 +239,7 @@ fn do_float(
     point: &Vector,
     size: Real,
     strength: Real,
+    buoyancy: Real
 ) {
     let point = body.position().transform_point(*point);
 
@@ -210,7 +265,7 @@ fn do_float(
     let volume = overlap.unwrap().volume();
 
     body.add_force_at_point(
-        Vector::new(0.0, 10.5 * volume * strength, 0.0),
+        Vector::new(0.0, 10.5 * volume * strength * buoyancy, 0.0),
         point,
         false,
     );