diff --git a/examples/processes/voxelizers.yaml b/examples/processes/voxelizers.yaml
new file mode 100644
index 000000000..40bfb3fd0
--- /dev/null
+++ b/examples/processes/voxelizers.yaml
@@ -0,0 +1,69 @@
+heightmaps:
+  ground:
+    default: 0
+  water:
+    default: 0
+
+forEachTile:
+
+  fetchAltitude:
+    type: fetchData
+    modelType: altitude
+    provider:
+      type: wmsFloat
+      url: https://data.geopf.fr/wms-r/wms
+      layer: RGEALTI-MNT_PYR-ZIP_FXX_LAMB93_WMS
+    processor:
+      type: floatMatrix
+    retry: 5
+    retryDelay: 1
+
+  setAltitude:
+    after: fetchAltitude
+    type: populateHeightmap
+    models:
+      type: altitude
+    heightmap: ground
+
+  setSpawn:
+    after: setAltitude
+    type: setSpawn
+    heightmap:
+      sum: [ground, 1]
+    x: 0
+    y: 0
+
+  renderGround:
+    after: setAltitude
+    type: renderHeightmap
+    at: ground
+    place:
+      structure:
+        - put: *voxel-grass
+          at: [0, 0, 0]
+        - put: *voxel-dirt
+          at: [0, 0, -3..-1]
+        - put: *voxel-stone
+          at: [0, 0, -20..-4]
+
+  fetchBuildings:
+    type: fetchData
+    modelType: buildings
+    provider:
+      type: wfs
+      url: https://data.geopf.fr/wfs/wfs
+      features: BDTOPO_V3:batiment
+      maxFeaturesPerQuery: 500
+
+  renderBuildings:
+    after: fetchBuildings
+    type: place
+    models:
+      type: buildings
+    voxels:
+      type: setAltitude
+      voxels:
+        type: surface
+      altitude: ground
+    place: default:sand
+
diff --git a/src/main/java/com/ignfab/minalac/generator/MinalacGenerator.java b/src/main/java/com/ignfab/minalac/generator/MinalacGenerator.java
index 99e5f1cf4..df58e893a 100644
--- a/src/main/java/com/ignfab/minalac/generator/MinalacGenerator.java
+++ b/src/main/java/com/ignfab/minalac/generator/MinalacGenerator.java
@@ -40,6 +40,7 @@
 import com.ignfab.minalac.generator.parameters.tasks.FillBetweenHeightmapAndMetadataTaskParams;
 import com.ignfab.minalac.generator.parameters.tasks.HeightmapStatsTaskParams;
 import com.ignfab.minalac.generator.parameters.tasks.NoOperationTaskParams;
+import com.ignfab.minalac.generator.parameters.tasks.PlaceTaskParams;
 import com.ignfab.minalac.generator.parameters.tasks.PopulateHeightmapTaskParams;
 import com.ignfab.minalac.generator.parameters.tasks.RenderBuildingsTaskParams;
 import com.ignfab.minalac.generator.parameters.tasks.RenderHeightmapTaskParams;
@@ -51,6 +52,8 @@
 import com.ignfab.minalac.generator.parameters.tasks.ScheduleTaskParams;
 import com.ignfab.minalac.generator.parameters.tasks.SequenceTaskParams;
 import com.ignfab.minalac.generator.parameters.tasks.SetSpawnTaskParams;
+import com.ignfab.minalac.generator.parameters.voxelizers.voxelizers2d.Voxelizer2dParams;
+import com.ignfab.minalac.generator.parameters.voxelizers.voxelizers3d.Voxelizer3dParams;
 import com.ignfab.minalac.generator.utils.FileHelpers;
 import com.ignfab.minalac.generator.utils.execution.TaskFailedException;
 import com.ignfab.minalac.generator.utils.modules.ModulesLoader;
@@ -124,6 +127,7 @@ public static void main(String[] args) throws FactoryException, InterruptedExcep
         parser.registerParams("computeHeightmapStats", HeightmapStatsTaskParams.class);
         parser.registerParams("fetchData", FetchDataTaskParams.class);
         parser.registerParams("fillBetweenHeightmapAndMetadata", FillBetweenHeightmapAndMetadataTaskParams.class);
+        parser.registerParams("place", PlaceTaskParams.class);
         parser.registerParams("populateHeightmap", PopulateHeightmapTaskParams.class);
         parser.registerParams("renderBuildings", RenderBuildingsTaskParams.class);
         parser.registerParams("renderHeightmap", RenderHeightmapTaskParams.class);
@@ -155,6 +159,9 @@ public static void main(String[] args) throws FactoryException, InterruptedExcep
         parser.registerParams("geometryBuffer", JTSGeometryBufferPostProcessorParams.class);
         parser.registerParams("remap", MetadataValueMappingPostProcessorParams.class);
 
+        Voxelizer2dParams.register(parser);
+        Voxelizer3dParams.register(parser);
+
         modules.registerParams(parser);
 
         Generation generation = parser.parse(parameters).create(destination, maxTileSize);
diff --git a/src/main/java/com/ignfab/minalac/generator/generation/Generation.java b/src/main/java/com/ignfab/minalac/generator/generation/Generation.java
index 6f1fae4f9..92622c03f 100644
--- a/src/main/java/com/ignfab/minalac/generator/generation/Generation.java
+++ b/src/main/java/com/ignfab/minalac/generator/generation/Generation.java
@@ -51,6 +51,22 @@ public class Generation {
     private final Collection<WorldBBox2d> tiles;
 
     private final Iterator<GenerationTile> tileIterator;
+
+    private static Generation currentGeneration = null;
+
+    /**
+     * @return current generation.
+     */
+    public static Generation current() {
+        if (currentGeneration == null)
+            throw new IllegalStateException("No current generation!");
+        return currentGeneration;
+    }
+
+    /* package private */ static void setCurrent(Generation generation) {
+        currentGeneration = generation;
+    }
+
     /**
      * Constructs a new generation context.
      * It sets {@code VoxelWorld}'s limits in way the center is at {@code WorldCoords2d} (0, 0).
@@ -115,6 +131,9 @@ public Generation(
         voxelToCrs.rotate(angle);
         voxelToCrs.scale(horizontalScale, horizontalScale);
         voxelToCrs.translate(centerX, centerY);
+
+        // TODO: MANAGE THAT WITH SCOPED VALUES
+        setCurrent(this);
     }
 
     /**
diff --git a/src/main/java/com/ignfab/minalac/generator/models/FloatMatrixModel.java b/src/main/java/com/ignfab/minalac/generator/models/FloatMatrixModel.java
index d6dbc8098..3af21966f 100644
--- a/src/main/java/com/ignfab/minalac/generator/models/FloatMatrixModel.java
+++ b/src/main/java/com/ignfab/minalac/generator/models/FloatMatrixModel.java
@@ -7,7 +7,7 @@
 import com.ignfab.minalac.generator.utils.coordinates.WorldToMapConverter;
 import com.ignfab.minalac.generator.utils.world2d.WorldBBox2d;
 import com.ignfab.minalac.generator.utils.world2d.WorldCoords2d;
-import com.ignfab.minalac.generator.voxelization.Matrix2d;
+import com.ignfab.minalac.generator.voxelization.matrix2d.Matrix2d;
 
 /**
  * A model based on a matrix of floats (usually a heightmap model).
diff --git a/src/main/java/com/ignfab/minalac/generator/models/Voxelizable2d.java b/src/main/java/com/ignfab/minalac/generator/models/Voxelizable2d.java
deleted file mode 100644
index f6e9df569..000000000
--- a/src/main/java/com/ignfab/minalac/generator/models/Voxelizable2d.java
+++ /dev/null
@@ -1,24 +0,0 @@
-package com.ignfab.minalac.generator.models;
-
-import com.ignfab.minalac.generator.utils.world2d.WorldBBox2d;
-import com.ignfab.minalac.generator.voxelization.Voxelizer2d;
-
-/**
- * Represents a model that can be transformed into 2d voxels using a voxelizer.
- */
-public interface Voxelizable2d extends Model {
-    /**
-     * Provides a voxelizer that returns voxels representing this model in 2d.
-     * The voxelizer must only return voxels inside the given bounding box.
-     * <p>
-     * Note that the voxelizer is not required to:
-     * <ul>
-     * <li>return a voxel for every position in the given bounding box
-     * <li>return a single voxel per position (it may return duplicates)
-     * </ul>
-     *
-     * @param bbox the limits for this voxelization.
-     * @return a {@link Voxelizer2d} to represent this object in 2d voxels.
-     */
-    Voxelizer2d voxelize2d(WorldBBox2d bbox);
-}
diff --git a/src/main/java/com/ignfab/minalac/generator/models/Voxelizable3d.java b/src/main/java/com/ignfab/minalac/generator/models/Voxelizable3d.java
deleted file mode 100644
index e16af2ecc..000000000
--- a/src/main/java/com/ignfab/minalac/generator/models/Voxelizable3d.java
+++ /dev/null
@@ -1,26 +0,0 @@
-package com.ignfab.minalac.generator.models;
-
-import com.ignfab.minalac.generator.utils.world3d.WorldBBox3d;
-import com.ignfab.minalac.generator.voxelization.Voxelizer3d;
-
-/**
- * Represents an object that can be transformed into 3d voxels using a voxelizer.
- * This interface usually applies to models.
- * Most models representable in 3d can also be represented in 2d, but this is not always the case!
- */
-public interface Voxelizable3d extends Model {
-    /**
-     * Provides a voxelizer that returns voxels representing this model in 3d.
-     * The voxelizer must only return voxels inside the given bounding box.
-     * <p>
-     * Note that the voxelizer is not required to:
-     * <ul>
-     * <li>return a voxel for every position in the given bounding box
-     * <li>return a single voxel per position (it may return duplicates)
-     * </ul>
-     *
-     * @param bbox the limits for this voxelization.
-     * @return a {@link Voxelizer3d} to represent this object in 3d voxels.
-     */
-    Voxelizer3d voxelize3d(WorldBBox3d bbox);
-}
diff --git a/src/main/java/com/ignfab/minalac/generator/parameters/tasks/PlaceTaskParams.java b/src/main/java/com/ignfab/minalac/generator/parameters/tasks/PlaceTaskParams.java
new file mode 100644
index 000000000..6eccdb877
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/parameters/tasks/PlaceTaskParams.java
@@ -0,0 +1,59 @@
+package com.ignfab.minalac.generator.parameters.tasks;
+
+import java.beans.ConstructorProperties;
+
+import com.fasterxml.jackson.annotation.JsonSetter;
+import com.fasterxml.jackson.annotation.Nulls;
+
+import com.ignfab.minalac.generator.generation.Generation;
+import com.ignfab.minalac.generator.parameters.placeables.PlaceableParams;
+import com.ignfab.minalac.generator.parameters.voxelizers.voxelizers3d.Voxelizer3dParams;
+import com.ignfab.minalac.generator.tasks.PlaceTask;
+import com.ignfab.minalac.generator.utils.execution.Task;
+
+/**
+ * Parameters for a {@link PlaceTask}.
+ */
+public class PlaceTaskParams extends ModelTaskParams {
+
+    /**
+     * Voxelizer to use to determine where to place (required).
+     */
+    @JsonSetter(nulls = Nulls.FAIL)
+    public Voxelizer3dParams voxels;
+
+    /**
+     * Placeable to place at points (required).
+     */
+    @JsonSetter(nulls = Nulls.FAIL)
+    public PlaceableParams place;
+
+    /**
+     * Constructor used to ensure that the required fields are present during deserialization.
+     *
+     * @param voxels where to place
+     * @param place what to place
+     */
+    @ConstructorProperties({ "voxels", "place"})
+    public PlaceTaskParams(Voxelizer3dParams voxels, PlaceableParams place) {
+        this.voxels = voxels;
+        this.place = place;
+    }
+
+    @Override
+    public void validate() {
+        super.validate();
+        voxels.validate();
+        place.validate();
+    }
+
+    @Override
+    public Task create(Generation generation) {
+        return new PlaceTask(
+            models.create(),
+            voxels.create(),
+            place.create(generation.seed())
+        );
+    }
+
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/PointVoxelizer2dParams.java b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/PointVoxelizer2dParams.java
new file mode 100644
index 000000000..9d8496db8
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/PointVoxelizer2dParams.java
@@ -0,0 +1,15 @@
+package com.ignfab.minalac.generator.parameters.voxelizers.voxelizers2d;
+
+import com.ignfab.minalac.generator.voxelization.Voxelizer2d;
+import com.ignfab.minalac.generator.voxelization.shape2d.voxelizer.PointVoxelizer2d;
+
+/**
+ * Parameters for a {@link PointVoxelizer2d}.
+ */
+public class PointVoxelizer2dParams extends Voxelizer2dParams {
+
+    @Override
+    public Voxelizer2d create() {
+        return new PointVoxelizer2d();
+    }
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/SurfaceVoxelizer2dParams.java b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/SurfaceVoxelizer2dParams.java
new file mode 100644
index 000000000..34adecc7c
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/SurfaceVoxelizer2dParams.java
@@ -0,0 +1,15 @@
+package com.ignfab.minalac.generator.parameters.voxelizers.voxelizers2d;
+
+import com.ignfab.minalac.generator.voxelization.Voxelizer2d;
+import com.ignfab.minalac.generator.voxelization.shape2d.voxelizer.SurfaceVoxelizer2d;
+
+/**
+ * Parameters for a {@link SurfaceVoxelizer2d}.
+ */
+public class SurfaceVoxelizer2dParams extends Voxelizer2dParams {
+
+    @Override
+    public Voxelizer2d create() {
+        return new SurfaceVoxelizer2d();
+    }
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/ThickLineVoxelizer2dParams.java b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/ThickLineVoxelizer2dParams.java
new file mode 100644
index 000000000..76fec9990
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/ThickLineVoxelizer2dParams.java
@@ -0,0 +1,24 @@
+package com.ignfab.minalac.generator.parameters.voxelizers.voxelizers2d;
+
+import com.fasterxml.jackson.annotation.JsonSetter;
+import com.fasterxml.jackson.annotation.Nulls;
+
+import com.ignfab.minalac.generator.voxelization.Voxelizer2d;
+import com.ignfab.minalac.generator.voxelization.shape2d.voxelizer.ThickLinearIndexedVoxelizer2d;
+
+/**
+ * Parameters for a {@link ThickLinearIndexedVoxelizer2d}.
+ */
+public class ThickLineVoxelizer2dParams extends Voxelizer2dParams {
+
+    /**
+     * Thickness of the line, in voxels.
+     */
+    @JsonSetter(nulls = Nulls.SKIP)
+    public double thickness = 1.0;
+
+    @Override
+    public Voxelizer2d create() {
+        return new ThickLinearIndexedVoxelizer2d(thickness);
+    }
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/ThinLinearVoxelizer2dParams.java b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/ThinLinearVoxelizer2dParams.java
new file mode 100644
index 000000000..f319194e8
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/ThinLinearVoxelizer2dParams.java
@@ -0,0 +1,15 @@
+package com.ignfab.minalac.generator.parameters.voxelizers.voxelizers2d;
+
+import com.ignfab.minalac.generator.voxelization.Voxelizer2d;
+import com.ignfab.minalac.generator.voxelization.shape2d.voxelizer.ThinLinearVoxelizer2d;
+
+/**
+ * Parameters for a {@link ThinLinearVoxelizer2dParams}.
+ */
+public class ThinLinearVoxelizer2dParams extends Voxelizer2dParams {
+
+    @Override
+    public Voxelizer2d create() {
+        return new ThinLinearVoxelizer2d();
+    }
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/ToVoxelizer2dParams.java b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/ToVoxelizer2dParams.java
new file mode 100644
index 000000000..2ac50fa66
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/ToVoxelizer2dParams.java
@@ -0,0 +1,41 @@
+package com.ignfab.minalac.generator.parameters.voxelizers.voxelizers2d;
+
+import java.beans.ConstructorProperties;
+
+import com.fasterxml.jackson.annotation.JsonSetter;
+import com.fasterxml.jackson.annotation.Nulls;
+
+import com.ignfab.minalac.generator.parameters.voxelizers.voxelizers3d.Voxelizer3dParams;
+import com.ignfab.minalac.generator.voxelization.ToVoxelizer2d;
+import com.ignfab.minalac.generator.voxelization.Voxelizer2d;
+
+/**
+ * Parameters for a {@link ToVoxelizer2d}.
+ */
+public class ToVoxelizer2dParams extends Voxelizer2dParams {
+    /**
+     * Voxels (from voxelizer) to turn to 2d.
+     */
+    @JsonSetter(nulls = Nulls.FAIL)
+    public Voxelizer3dParams voxels;
+
+    /**
+     * Constructor used to ensure that the required fields are present during deserialization.
+     *
+     * @param voxels voxelizer to transform
+     */
+    @ConstructorProperties({ "voxels" })
+    public ToVoxelizer2dParams(Voxelizer3dParams voxels) {
+        this.voxels = voxels;
+    }
+
+    @Override
+    public void validate() {
+        voxels.validate();
+    }
+
+    @Override
+    public Voxelizer2d create() {
+        return new ToVoxelizer2d(voxels.create());
+    }
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/Voxelizer2dParams.java b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/Voxelizer2dParams.java
new file mode 100644
index 000000000..c8c6b2a27
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers2d/Voxelizer2dParams.java
@@ -0,0 +1,31 @@
+package com.ignfab.minalac.generator.parameters.voxelizers.voxelizers2d;
+
+import com.ignfab.minalac.generator.parameters.ParamsParser;
+import com.ignfab.minalac.generator.parameters.PolymorphicParams;
+import com.ignfab.minalac.generator.voxelization.Voxelizer2d;
+
+/**
+ * Parameters for a {@link Voxelizer2d}.
+ */
+public abstract class Voxelizer2dParams extends PolymorphicParams {
+
+    /**
+     * Creates a {@link Voxelizer2d} from parameters.
+     *
+     * @return created voxelizer
+     */
+    public abstract Voxelizer2d create();
+
+    /**
+     * Registers all voxelizers into a given {@link ParamsParser}.
+     *
+     * @param parser parser into which register voxelizers
+     */
+    public static void register(ParamsParser parser) {
+        parser.registerParams("point", PointVoxelizer2dParams.class);
+        parser.registerParams("thickLine", ThickLineVoxelizer2dParams.class);
+        parser.registerParams("line", ThinLinearVoxelizer2dParams.class);
+        parser.registerParams("surface", SurfaceVoxelizer2dParams.class);
+        parser.registerParams("to2d", ToVoxelizer2dParams.class);
+    }
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers3d/PointVoxelizer3dParams.java b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers3d/PointVoxelizer3dParams.java
new file mode 100644
index 000000000..1b7165eb9
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers3d/PointVoxelizer3dParams.java
@@ -0,0 +1,15 @@
+package com.ignfab.minalac.generator.parameters.voxelizers.voxelizers3d;
+
+import com.ignfab.minalac.generator.voxelization.Voxelizer3d;
+import com.ignfab.minalac.generator.voxelization.shape3d.voxelizer.PointVoxelizer3d;
+
+/**
+ * Parameters for a {@link PointVoxelizer3d}.
+ */
+public class PointVoxelizer3dParams extends Voxelizer3dParams {
+
+    @Override
+    public Voxelizer3d create() {
+        return new PointVoxelizer3d();
+    }
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers3d/SetAtlitudeVoxelizer3dParams.java b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers3d/SetAtlitudeVoxelizer3dParams.java
new file mode 100644
index 000000000..6f9e4fc54
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers3d/SetAtlitudeVoxelizer3dParams.java
@@ -0,0 +1,52 @@
+package com.ignfab.minalac.generator.parameters.voxelizers.voxelizers3d;
+
+import java.beans.ConstructorProperties;
+
+import com.fasterxml.jackson.annotation.JsonSetter;
+import com.fasterxml.jackson.annotation.Nulls;
+
+import com.ignfab.minalac.generator.generation.Generation;
+import com.ignfab.minalac.generator.parameters.heightmaps.ReadableHeightmapParams;
+import com.ignfab.minalac.generator.parameters.voxelizers.voxelizers2d.Voxelizer2dParams;
+import com.ignfab.minalac.generator.voxelization.SetAltitudeVoxelizer3d;
+import com.ignfab.minalac.generator.voxelization.Voxelizer3d;
+
+/**
+ * Parameters for a {@link SetAltitudeVoxelizer3d}.
+ */
+public class SetAtlitudeVoxelizer3dParams extends Voxelizer3dParams {
+    /**
+     * Voxels (from voxelizer) to turn to 3d.
+     */
+    @JsonSetter(nulls = Nulls.FAIL)
+    public Voxelizer2dParams voxels;
+
+    /**
+     * Altitude (from heightmap) to set as z-coordinate.
+     */
+    @JsonSetter(nulls = Nulls.FAIL)
+    public ReadableHeightmapParams altitude;
+
+    /**
+     * Constructor used to ensure that the required fields are present during deserialization.
+     *
+     * @param voxels voxelizer to transform
+     * @param altitude heightmap to fetch altitudes from
+     */
+    @ConstructorProperties({ "voxels", "altitude" })
+    public SetAtlitudeVoxelizer3dParams(Voxelizer2dParams voxels, ReadableHeightmapParams altitude) {
+        this.voxels = voxels;
+        this.altitude = altitude;
+    }
+
+    @Override
+    public void validate() {
+        altitude.validate();
+        voxels.validate();
+    }
+
+    @Override
+    public Voxelizer3d create() {
+        return new SetAltitudeVoxelizer3d(voxels.create(), altitude.create(Generation.current().heightmaps()));
+    }
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers3d/ThickLineVoxelizer3dParams.java b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers3d/ThickLineVoxelizer3dParams.java
new file mode 100644
index 000000000..662423636
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers3d/ThickLineVoxelizer3dParams.java
@@ -0,0 +1,24 @@
+package com.ignfab.minalac.generator.parameters.voxelizers.voxelizers3d;
+
+import com.fasterxml.jackson.annotation.JsonSetter;
+import com.fasterxml.jackson.annotation.Nulls;
+
+import com.ignfab.minalac.generator.voxelization.Voxelizer3d;
+import com.ignfab.minalac.generator.voxelization.shape3d.voxelizer.ThickLinearIndexedVoxelizer2d5;
+
+/**
+ * Parameters for a {@link ThickLinearIndexedVoxelizer2d5}.
+ */
+public class ThickLineVoxelizer3dParams extends Voxelizer3dParams {
+
+    /**
+     * Thickness of the line, in voxels.
+     */
+    @JsonSetter(nulls = Nulls.SKIP)
+    public double thickness = 1.0;
+
+    @Override
+    public Voxelizer3d create() {
+        return new ThickLinearIndexedVoxelizer2d5(thickness);
+    }
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers3d/Voxelizer3dParams.java b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers3d/Voxelizer3dParams.java
new file mode 100644
index 000000000..c4d339fef
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/parameters/voxelizers/voxelizers3d/Voxelizer3dParams.java
@@ -0,0 +1,29 @@
+package com.ignfab.minalac.generator.parameters.voxelizers.voxelizers3d;
+
+import com.ignfab.minalac.generator.parameters.ParamsParser;
+import com.ignfab.minalac.generator.parameters.PolymorphicParams;
+import com.ignfab.minalac.generator.voxelization.Voxelizer3d;
+
+/**
+ * Parameters for a {@link Voxelizer3d}.
+ */
+public abstract class Voxelizer3dParams extends PolymorphicParams {
+
+    /**
+     * Creates a {@link Voxelizer3d} from parameters.
+     *
+     * @return created voxelizer
+     */
+    public abstract Voxelizer3d create();
+
+    /**
+     * Registers all voxelizers into a given {@link ParamsParser}.
+     *
+     * @param parser parser into which register voxelizers
+     */
+    public static void register(ParamsParser parser) {
+        parser.registerParams("point", PointVoxelizer3dParams.class);
+        parser.registerParams("line", ThickLineVoxelizer3dParams.class);
+        parser.registerParams("setAltitude", SetAtlitudeVoxelizer3dParams.class);
+    }
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/tasks/PlaceTask.java b/src/main/java/com/ignfab/minalac/generator/tasks/PlaceTask.java
new file mode 100644
index 000000000..b800e5c55
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/tasks/PlaceTask.java
@@ -0,0 +1,35 @@
+package com.ignfab.minalac.generator.tasks;
+
+import com.ignfab.minalac.generator.generation.GenerationTile;
+import com.ignfab.minalac.generator.models.Model;
+import com.ignfab.minalac.generator.models.ModelSelection;
+import com.ignfab.minalac.generator.placeables.Placeable;
+import com.ignfab.minalac.generator.utils.world3d.Positioned3d;
+import com.ignfab.minalac.generator.voxelization.Voxelizer3d;
+
+/**
+ * A task placing a placeable according to a given voxelizer.
+ */
+public class PlaceTask extends ModelTask<Model> {
+    private final Voxelizer3d voxelizer;
+    private final Placeable placeable;
+
+    /**
+     * Creates a new {@code PlaceTask}.
+     *
+     * @param selection Selection of models to voxelize
+     * @param voxelizer Voxelizer to use
+     * @param placeable What to place on each voxel
+     */
+    public PlaceTask(ModelSelection selection, Voxelizer3d voxelizer, Placeable placeable) {
+        super(Model.class, selection);
+        this.voxelizer = voxelizer;
+        this.placeable = placeable;
+    }
+
+    @Override
+    protected void run(Model model, GenerationTile tile) {
+        for (Positioned3d pos : tile.limits().filterInside(voxelizer.voxelize(model)))
+            placeable.place(tile.voxels(), pos.coords());
+    }
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/tasks/PopulateHeightmapTask.java b/src/main/java/com/ignfab/minalac/generator/tasks/PopulateHeightmapTask.java
index cf6cc3b90..307951569 100644
--- a/src/main/java/com/ignfab/minalac/generator/tasks/PopulateHeightmapTask.java
+++ b/src/main/java/com/ignfab/minalac/generator/tasks/PopulateHeightmapTask.java
@@ -7,7 +7,7 @@
 import com.ignfab.minalac.generator.models.ModelSelection;
 import com.ignfab.minalac.generator.utils.world2d.WorldBBox2d;
 import com.ignfab.minalac.generator.utils.world2d.WorldCoords2d;
-import com.ignfab.minalac.generator.voxelization.Matrix2d;
+import com.ignfab.minalac.generator.voxelization.matrix2d.Matrix2d;
 
 /**
  * A {@link TileTask} copying data from a {@link ModelSelection} to a heightmap.
diff --git a/src/main/java/com/ignfab/minalac/generator/tasks/RenderPoints2dTask.java b/src/main/java/com/ignfab/minalac/generator/tasks/RenderPoints2dTask.java
index a93ea3cde..e4f0b900f 100644
--- a/src/main/java/com/ignfab/minalac/generator/tasks/RenderPoints2dTask.java
+++ b/src/main/java/com/ignfab/minalac/generator/tasks/RenderPoints2dTask.java
@@ -8,7 +8,7 @@
 import com.ignfab.minalac.generator.placeables.Placeable;
 import com.ignfab.minalac.generator.utils.world2d.Positioned2d;
 import com.ignfab.minalac.generator.utils.world2d.WorldCoords2d;
-import com.ignfab.minalac.generator.voxelization.shape2d.voxelizer.Point2dVoxelizer;
+import com.ignfab.minalac.generator.voxelization.shape2d.voxelizer.PointVoxelizer2d;
 
 /**
  * A task rendering points by placing placeables at them.
@@ -16,7 +16,7 @@
 public class RenderPoints2dTask extends ModelTask<Shape2dConvertibleModel> {
     private final Placeable placeable;
     private final ReadableHeightmapSpec heightmapSpec;
-    private final Point2dVoxelizer voxelizer;
+    private final PointVoxelizer2d voxelizer;
 
     /**
      * Creates a new {@code RenderPoints2dTask}.
@@ -33,7 +33,7 @@ public RenderPoints2dTask(
         super(Shape2dConvertibleModel.class, selection);
         this.placeable = placeable;
         this.heightmapSpec = heightmapSpec;
-        voxelizer = new Point2dVoxelizer();
+        voxelizer = new PointVoxelizer2d();
     }
 
     @Override
diff --git a/src/main/java/com/ignfab/minalac/generator/tasks/RenderPointsTask.java b/src/main/java/com/ignfab/minalac/generator/tasks/RenderPointsTask.java
index 8af23dd75..ee5a44d11 100644
--- a/src/main/java/com/ignfab/minalac/generator/tasks/RenderPointsTask.java
+++ b/src/main/java/com/ignfab/minalac/generator/tasks/RenderPointsTask.java
@@ -5,14 +5,14 @@
 import com.ignfab.minalac.generator.models.Shape3dConvertibleModel;
 import com.ignfab.minalac.generator.placeables.Placeable;
 import com.ignfab.minalac.generator.utils.world3d.Positioned3d;
-import com.ignfab.minalac.generator.voxelization.shape3d.voxelizer.Point3dVoxelizer;
+import com.ignfab.minalac.generator.voxelization.shape3d.voxelizer.PointVoxelizer3d;
 
 /**
  * A task rendering points by placing placeables at them.
  */
 public class RenderPointsTask extends ModelTask<Shape3dConvertibleModel> {
     private final Placeable placeable;
-    private final Point3dVoxelizer voxelizer;
+    private final PointVoxelizer3d voxelizer;
 
     /**
      * Creates a new {@code RenderPointsTask}.
@@ -26,7 +26,7 @@ public RenderPointsTask(
     ) {
         super(Shape3dConvertibleModel.class, selection);
         this.placeable = placeable;
-        voxelizer = new Point3dVoxelizer();
+        voxelizer = new PointVoxelizer3d();
     }
 
     @Override
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/SetAltitudeVoxelizer3d.java b/src/main/java/com/ignfab/minalac/generator/voxelization/SetAltitudeVoxelizer3d.java
new file mode 100644
index 000000000..e19a67b11
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/SetAltitudeVoxelizer3d.java
@@ -0,0 +1,40 @@
+package com.ignfab.minalac.generator.voxelization;
+
+import com.ignfab.minalac.generator.generation.GenerationTile;
+import com.ignfab.minalac.generator.generation.heightmaps.ReadableHeightmap;
+import com.ignfab.minalac.generator.generation.heightmaps.ReadableHeightmapSpec;
+import com.ignfab.minalac.generator.models.Model;
+import com.ignfab.minalac.generator.utils.iterator.Iterables;
+import com.ignfab.minalac.generator.utils.world3d.Positioned3d;
+
+/**
+ * A 3d voxelizer adding a z-coordinate to voxels from a 2d voxelizer.
+ */
+public class SetAltitudeVoxelizer3d implements Voxelizer3d {
+
+    private final Voxelizer2d voxelizer;
+    private final ReadableHeightmapSpec altitude;
+
+    /**
+     * Creates a new {@code SetAltitudeVoxelizer3d}.
+     *
+     * @param voxelizer 2d voxelizer to get horizontal coordinates from
+     * @param altitude heightmap giving the vertical coordinate
+     */
+    public SetAltitudeVoxelizer3d(Voxelizer2d voxelizer, ReadableHeightmapSpec altitude) {
+        this.voxelizer = voxelizer;
+        this.altitude = altitude;
+    }
+
+    @Override
+    public Iterable<? extends Positioned3d> voxelize(Model model) {
+        // TODO: This could move into a HeightmapSpec method
+        ReadableHeightmap heightmap = GenerationTile.current().heightmap(altitude);
+
+        return Iterables.remap(
+            // TODO: If we had voxelizers already filtered by current tile, we wouldn't need to filter here
+            heightmap.bbox().filterInside(voxelizer.voxelize(model)),
+            (pos) -> pos.coords().to3d(heightmap.get(pos.coords()))
+        );
+    }
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/ToVoxelizer2d.java b/src/main/java/com/ignfab/minalac/generator/voxelization/ToVoxelizer2d.java
new file mode 100644
index 000000000..9462b4650
--- /dev/null
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/ToVoxelizer2d.java
@@ -0,0 +1,30 @@
+package com.ignfab.minalac.generator.voxelization;
+
+import com.ignfab.minalac.generator.models.Model;
+import com.ignfab.minalac.generator.utils.iterator.Iterables;
+import com.ignfab.minalac.generator.utils.world2d.Positioned2d;
+
+/**
+ * A 2d voxelizer flattening voxels from a 3d voxelizer.
+ */
+public class ToVoxelizer2d implements Voxelizer2d {
+
+    private final Voxelizer3d voxelizer;
+
+    /**
+     * Creates a new {@code ToVoxelizer2d}.
+     *
+     * @param voxelizer voxelizer to flatted to 2d
+     */
+    public ToVoxelizer2d(Voxelizer3d voxelizer) {
+        this.voxelizer = voxelizer;
+    }
+
+    @Override
+    public Iterable<Positioned2d> voxelize(Model model) {
+        return Iterables.remap(
+            voxelizer.voxelize(model),
+            (pos) -> pos.coords().to2d()
+        );
+    }
+}
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/Voxelizer2d.java b/src/main/java/com/ignfab/minalac/generator/voxelization/Voxelizer2d.java
index f4a7de2c5..45e87378f 100644
--- a/src/main/java/com/ignfab/minalac/generator/voxelization/Voxelizer2d.java
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/Voxelizer2d.java
@@ -1,22 +1,19 @@
 package com.ignfab.minalac.generator.voxelization;
 
-import java.util.Iterator;
-
+import com.ignfab.minalac.generator.models.Model;
 import com.ignfab.minalac.generator.utils.world2d.Positioned2d;
 
 /**
- * A 2d voxelizer provides a way to iterate over 2d voxels.
- * This is the minimal voxelizer, which only tells which voxels are in the model.
- * <p>
- * The voxels returned by iterators are not guaranteed to be unique:
- * It may contain duplicate coordinate.
+ * A voxelizer converting a model into 2d voxels.
  */
-public interface Voxelizer2d extends Iterable<Positioned2d> {
+public interface Voxelizer2d {
     /**
-     * Returns an iterator over all the voxels in this object.
+     * Performs voxelization of a {@link Model} into an iterable over 2d positions.
+     * <p>
+     * If unable to voxelize model, returns an empty iterator.
      *
-     * @return the global iterator of this object.
+     * @param model model to voxelize
+     * @return iterable over corresponding voxel positions
      */
-    @Override
-    Iterator<Positioned2d> iterator();
+    Iterable<? extends Positioned2d> voxelize(Model model);
 }
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/Voxelizer3d.java b/src/main/java/com/ignfab/minalac/generator/voxelization/Voxelizer3d.java
index 9e25abcc1..3c7eaa765 100644
--- a/src/main/java/com/ignfab/minalac/generator/voxelization/Voxelizer3d.java
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/Voxelizer3d.java
@@ -1,22 +1,19 @@
 package com.ignfab.minalac.generator.voxelization;
 
-import java.util.Iterator;
-
+import com.ignfab.minalac.generator.models.Model;
 import com.ignfab.minalac.generator.utils.world3d.Positioned3d;
 
 /**
- * A 3d voxelizer provides a way to iterate over 3d voxels.
- * This is the minimal voxelizer, which only tells which voxels are in the model.
- * <p>
- * The voxels returned by iterators are not guaranteed to be unique:
- * It may contain duplicate coordinate.
+ * A voxelizer converting a model into  3d voxels.
  */
-public interface Voxelizer3d extends Iterable<Positioned3d> {
+public interface Voxelizer3d {
     /**
-     * Returns an iterator over all the voxels in this object.
+     * Performs voxelization of a {@link Model} into an iterable over 3d positions.
+     * <p>
+     * If unable to voxelize model, returns an empty iterator.
      *
-     * @return the global iterator of this object.
+     * @param model model to voxelize
+     * @return iterable over corresponding voxel positions
      */
-    @Override
-    Iterator<Positioned3d> iterator();
+    Iterable<? extends Positioned3d> voxelize(Model model);
 }
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/Matrix2d.java b/src/main/java/com/ignfab/minalac/generator/voxelization/matrix2d/Matrix2d.java
similarity index 95%
rename from src/main/java/com/ignfab/minalac/generator/voxelization/Matrix2d.java
rename to src/main/java/com/ignfab/minalac/generator/voxelization/matrix2d/Matrix2d.java
index ce05bcc8c..c9afd6d0e 100644
--- a/src/main/java/com/ignfab/minalac/generator/voxelization/Matrix2d.java
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/matrix2d/Matrix2d.java
@@ -1,4 +1,4 @@
-package com.ignfab.minalac.generator.voxelization;
+package com.ignfab.minalac.generator.voxelization.matrix2d;
 
 import com.ignfab.minalac.generator.utils.world2d.Bounded2d;
 import com.ignfab.minalac.generator.utils.world2d.Positioned2d;
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/Matrix2dIterator.java b/src/main/java/com/ignfab/minalac/generator/voxelization/matrix2d/Matrix2dIterator.java
similarity index 95%
rename from src/main/java/com/ignfab/minalac/generator/voxelization/Matrix2dIterator.java
rename to src/main/java/com/ignfab/minalac/generator/voxelization/matrix2d/Matrix2dIterator.java
index cc8f30a0c..46ac62fdd 100644
--- a/src/main/java/com/ignfab/minalac/generator/voxelization/Matrix2dIterator.java
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/matrix2d/Matrix2dIterator.java
@@ -1,4 +1,4 @@
-package com.ignfab.minalac.generator.voxelization;
+package com.ignfab.minalac.generator.voxelization.matrix2d;
 
 import java.util.Iterator;
 
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/Point2dVoxelizer.java b/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/PointVoxelizer2d.java
similarity index 57%
rename from src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/Point2dVoxelizer.java
rename to src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/PointVoxelizer2d.java
index 95b1342a0..985b49464 100644
--- a/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/Point2dVoxelizer.java
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/PointVoxelizer2d.java
@@ -1,14 +1,14 @@
 package com.ignfab.minalac.generator.voxelization.shape2d.voxelizer;
 
 import com.ignfab.minalac.generator.utils.world2d.Positioned2d;
-import com.ignfab.minalac.generator.voxelization.shape2d.Shape2dConvertible;
+import com.ignfab.minalac.generator.voxelization.shape2d.Shape2d;
 
 /**
  * A voxelizer that returns the points of a 2D shape.
  */
-public class Point2dVoxelizer implements Shape2dVoxelizer {
+public class PointVoxelizer2d implements Shape2dVoxelizer {
     @Override
-    public Iterable<? extends Positioned2d> voxelize(Shape2dConvertible convertible) {
-        return convertible.toShape2d().points();
+    public Iterable<? extends Positioned2d> voxelizeShape2d(Shape2d shape) {
+        return shape.points();
     }
 }
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/Shape2dVoxelizer.java b/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/Shape2dVoxelizer.java
index 736b0a48a..bda06eea9 100644
--- a/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/Shape2dVoxelizer.java
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/Shape2dVoxelizer.java
@@ -1,17 +1,30 @@
 package com.ignfab.minalac.generator.voxelization.shape2d.voxelizer;
 
+import java.util.Collections;
+
+import com.ignfab.minalac.generator.models.Model;
 import com.ignfab.minalac.generator.utils.world2d.Positioned2d;
+import com.ignfab.minalac.generator.voxelization.Voxelizer2d;
+import com.ignfab.minalac.generator.voxelization.shape2d.Shape2d;
 import com.ignfab.minalac.generator.voxelization.shape2d.Shape2dConvertible;
 
 /**
- * Interface for voxelizers able to voxelize {@link Shape2dConvertible} into {@link Positioned2d}.
+ * Interface for voxelizers able to voxelize {@link Shape2dConvertible} models into {@link Positioned2d}.
  */
-public interface Shape2dVoxelizer {
+public interface Shape2dVoxelizer extends Voxelizer2d {
     /**
-     * Performs voxelization of a {@link Shape2dConvertible} into an iterable over 2d positions.
+     * Performs voxelization of a {@link Shape2d} into an iterable over 2d positions.
      *
-     * @param convertible something convertible into {@code Shape2d}
+     * @param shape shape to voxelize
      * @return iterable over corresponding voxel positions
      */
-    Iterable<? extends Positioned2d> voxelize(Shape2dConvertible convertible);
+    Iterable<? extends Positioned2d> voxelizeShape2d(Shape2d shape);
+
+    @Override
+    default Iterable<? extends Positioned2d> voxelize(Model model) {
+        if (model instanceof Shape2dConvertible convertible)
+            return voxelizeShape2d(convertible.toShape2d());
+        else
+            return Collections.emptyList();
+    }
 }
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/SurfaceVoxelizer2d.java b/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/SurfaceVoxelizer2d.java
index 91443746b..faf44da3a 100644
--- a/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/SurfaceVoxelizer2d.java
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/SurfaceVoxelizer2d.java
@@ -3,7 +3,7 @@
 import com.ignfab.minalac.generator.utils.iterator.Iterables;
 import com.ignfab.minalac.generator.utils.world2d.Positioned2d;
 import com.ignfab.minalac.generator.voxelization.shape2d.Polygon2d;
-import com.ignfab.minalac.generator.voxelization.shape2d.Shape2dConvertible;
+import com.ignfab.minalac.generator.voxelization.shape2d.Shape2d;
 import com.ignfab.minalac.generator.voxelization.shape2d.iterator.Polygon2dIterator;
 
 /**
@@ -21,8 +21,8 @@ public Iterable<Positioned2d> voxelize(Polygon2d polygon) {
     }
 
     @Override
-    public Iterable<Positioned2d> voxelize(Shape2dConvertible convertible) {
-        return Iterables.flatMap(convertible.toShape2d().polygons(), this::voxelize);
+    public Iterable<? extends Positioned2d> voxelizeShape2d(Shape2d shape) {
+        return Iterables.flatMap(shape.polygons(), this::voxelize);
     }
 
 }
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/ThickLinearIndexedVoxelizer2d.java b/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/ThickLinearIndexedVoxelizer2d.java
index a926cf20f..d7a11682c 100644
--- a/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/ThickLinearIndexedVoxelizer2d.java
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/ThickLinearIndexedVoxelizer2d.java
@@ -1,7 +1,11 @@
 package com.ignfab.minalac.generator.voxelization.shape2d.voxelizer;
 
+import java.util.Collections;
+
+import com.ignfab.minalac.generator.models.Model;
 import com.ignfab.minalac.generator.utils.iterator.Iterables;
 import com.ignfab.minalac.generator.voxelization.shape2d.LineString2d;
+import com.ignfab.minalac.generator.voxelization.shape2d.Shape2d;
 import com.ignfab.minalac.generator.voxelization.shape2d.Shape2dConvertible;
 import com.ignfab.minalac.generator.voxelization.shape2d.iterator.IndexedPosition2d;
 import com.ignfab.minalac.generator.voxelization.shape2d.iterator.ThickLineString2dIndexedIterator;
@@ -33,13 +37,21 @@ public ThickLinearIndexedVoxelizer2d(double thickness) {
      * @param lineString Line string to voxelize
      * @return an iterable over voxelized positions
      */
-    public Iterable<IndexedPosition2d> voxelize(LineString2d lineString) {
+    public Iterable<IndexedPosition2d> voxelizeShape2d(LineString2d lineString) {
         return () -> new ThickLineString2dIndexedIterator(lineString, thickness);
     }
 
     @Override
-    public Iterable<IndexedPosition2d> voxelize(Shape2dConvertible convertible) {
-        return Iterables.flatMap(convertible.toShape2d().lineStrings(), this::voxelize);
+        public Iterable<IndexedPosition2d> voxelizeShape2d(Shape2d shape) {
+        return Iterables.flatMap(shape.lineStrings(), this::voxelizeShape2d);
     }
 
+    // Needed to precise return type
+    @Override
+    public Iterable<IndexedPosition2d> voxelize(Model model) {
+        if (model instanceof Shape2dConvertible convertible)
+            return voxelizeShape2d(convertible.toShape2d());
+        else
+            return Collections.emptyList();
+    }
 }
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/ThinLinearVoxelizer2d.java b/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/ThinLinearVoxelizer2d.java
index 3bf28880a..ca4154b20 100644
--- a/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/ThinLinearVoxelizer2d.java
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/shape2d/voxelizer/ThinLinearVoxelizer2d.java
@@ -3,7 +3,7 @@
 import com.ignfab.minalac.generator.utils.iterator.Iterables;
 import com.ignfab.minalac.generator.utils.world2d.Positioned2d;
 import com.ignfab.minalac.generator.voxelization.shape2d.LineString2d;
-import com.ignfab.minalac.generator.voxelization.shape2d.Shape2dConvertible;
+import com.ignfab.minalac.generator.voxelization.shape2d.Shape2d;
 import com.ignfab.minalac.generator.voxelization.shape2d.iterator.ThinSegment2dIterator;
 
 /**
@@ -23,8 +23,8 @@ public Iterable<Positioned2d> voxelize(LineString2d lineString) {
     }
 
     @Override
-    public Iterable<Positioned2d> voxelize(Shape2dConvertible convertible) {
-        return Iterables.flatMap(convertible.toShape2d().lineStrings(), this::voxelize);
+    public Iterable<? extends Positioned2d> voxelizeShape2d(Shape2d shape) {
+        return Iterables.flatMap(shape.lineStrings(), this::voxelize);
     }
 
 }
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/Point3dVoxelizer.java b/src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/PointVoxelizer3d.java
similarity index 57%
rename from src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/Point3dVoxelizer.java
rename to src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/PointVoxelizer3d.java
index 0be3ddaf0..a18753c4f 100644
--- a/src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/Point3dVoxelizer.java
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/PointVoxelizer3d.java
@@ -1,14 +1,14 @@
 package com.ignfab.minalac.generator.voxelization.shape3d.voxelizer;
 
 import com.ignfab.minalac.generator.utils.world3d.Positioned3d;
-import com.ignfab.minalac.generator.voxelization.shape3d.Shape3dConvertible;
+import com.ignfab.minalac.generator.voxelization.shape3d.Shape3d;
 
 /**
  * A voxelizer that returns the points of a 3D shape.
  */
-public class Point3dVoxelizer implements Shape3dVoxelizer {
+public class PointVoxelizer3d implements Shape3dVoxelizer {
     @Override
-    public Iterable<? extends Positioned3d> voxelize(Shape3dConvertible convertible) {
-        return convertible.toShape3d().points();
+    public Iterable<? extends Positioned3d> voxelizeShape3d(Shape3d shape) {
+        return shape.points();
     }
 }
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/Shape3dVoxelizer.java b/src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/Shape3dVoxelizer.java
index e0510630f..051a2be89 100644
--- a/src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/Shape3dVoxelizer.java
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/Shape3dVoxelizer.java
@@ -1,17 +1,30 @@
 package com.ignfab.minalac.generator.voxelization.shape3d.voxelizer;
 
+import java.util.Collections;
+
+import com.ignfab.minalac.generator.models.Model;
 import com.ignfab.minalac.generator.utils.world3d.Positioned3d;
+import com.ignfab.minalac.generator.voxelization.Voxelizer3d;
+import com.ignfab.minalac.generator.voxelization.shape3d.Shape3d;
 import com.ignfab.minalac.generator.voxelization.shape3d.Shape3dConvertible;
 
 /**
- * Interface for voxelizers able to voxelize {@link Shape3dConvertible} into {@link Positioned3d}.
+ * Interface for voxelizers able to voxelize {@link Shape3dConvertible} models into {@link Positioned3d}.
  */
-public interface Shape3dVoxelizer {
+public interface Shape3dVoxelizer extends Voxelizer3d {
     /**
-     * Perform voxelization of a {@link Shape3dConvertible} into an iterable over 3d positions.
+     * Perform voxelization of a {@link Shape3d} into an iterable over 3d positions.
      *
-     * @param convertible something convertible into {@code Shape3d}
+     * @param shape shape to voxelize
      * @return iterable over corresponding voxel positions
      */
-    Iterable<? extends Positioned3d> voxelize(Shape3dConvertible convertible);
+    Iterable<? extends Positioned3d> voxelizeShape3d(Shape3d shape);
+
+    @Override
+    default Iterable<? extends Positioned3d> voxelize(Model model) {
+        if (model instanceof Shape3dConvertible convertible)
+            return voxelizeShape3d(convertible.toShape3d());
+        else
+            return Collections.emptyList();
+    }
 }
diff --git a/src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/ThickLinearIndexedVoxelizer2d5.java b/src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/ThickLinearIndexedVoxelizer2d5.java
index 8b2d01f69..4ef4f00f6 100644
--- a/src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/ThickLinearIndexedVoxelizer2d5.java
+++ b/src/main/java/com/ignfab/minalac/generator/voxelization/shape3d/voxelizer/ThickLinearIndexedVoxelizer2d5.java
@@ -1,7 +1,11 @@
 package com.ignfab.minalac.generator.voxelization.shape3d.voxelizer;
 
+import java.util.Collections;
+
+import com.ignfab.minalac.generator.models.Model;
 import com.ignfab.minalac.generator.utils.iterator.Iterables;
 import com.ignfab.minalac.generator.voxelization.shape3d.LineString3d;
+import com.ignfab.minalac.generator.voxelization.shape3d.Shape3d;
 import com.ignfab.minalac.generator.voxelization.shape3d.Shape3dConvertible;
 import com.ignfab.minalac.generator.voxelization.shape3d.iterator.IndexedPosition3d;
 import com.ignfab.minalac.generator.voxelization.shape3d.iterator.ThickLineString2d5IndexedIterator;
@@ -35,12 +39,22 @@ public ThickLinearIndexedVoxelizer2d5(double thickness) {
      * @param lineString Line string to voxelize
      * @return an iterable over voxelized positions and indexes
      */
-    public Iterable<IndexedPosition3d> voxelize(LineString3d lineString) {
+    public Iterable<IndexedPosition3d> voxelizeShape3d(LineString3d lineString) {
         return () -> new ThickLineString2d5IndexedIterator(lineString, thickness);
     }
 
     @Override
-    public Iterable<IndexedPosition3d> voxelize(Shape3dConvertible convertible) {
-        return Iterables.flatMap(convertible.toShape3d().lineStrings(), this::voxelize);
+    public Iterable<IndexedPosition3d> voxelizeShape3d(Shape3d shape) {
+        return Iterables.flatMap(shape.lineStrings(), this::voxelizeShape3d);
+    }
+
+    // Needed to precise return type
+    @Override
+    public Iterable<IndexedPosition3d> voxelize(Model model) {
+        if (model instanceof Shape3dConvertible convertible)
+            return voxelizeShape3d(convertible.toShape3d());
+        else
+            return Collections.emptyList();
     }
 }
+