diff --git a/lib_paysages/atmosphere.c b/lib_paysages/atmosphere.c
index 8b18604..101e2d5 100644
--- a/lib_paysages/atmosphere.c
+++ b/lib_paysages/atmosphere.c
@@ -5,14 +5,6 @@
 #include "color.h"
 #include "tools.h"
 
-void atmosphereInit()
-{
-}
-
-void atmosphereQuit()
-{
-}
-
 void atmosphereSave(PackStream* stream, AtmosphereDefinition* definition)
 {
     packWriteDouble(stream, &definition->distance_near);
diff --git a/lib_paysages/atmosphere.h b/lib_paysages/atmosphere.h
index ad1d2b7..1ec855f 100644
--- a/lib_paysages/atmosphere.h
+++ b/lib_paysages/atmosphere.h
@@ -19,8 +19,6 @@ typedef struct
     Color color;
 } AtmosphereDefinition;
 
-void atmosphereInit();
-void atmosphereQuit();
 void atmosphereSave(PackStream* stream, AtmosphereDefinition* definition);
 void atmosphereLoad(PackStream* stream, AtmosphereDefinition* definition);
 
diff --git a/lib_paysages/camera.c b/lib_paysages/camera.c
index 233f23c..21f67a6 100644
--- a/lib_paysages/camera.c
+++ b/lib_paysages/camera.c
@@ -9,14 +9,6 @@
 #include "scenery.h"
 #include "tools.h"
 
-void cameraInit()
-{
-}
-
-void cameraQuit()
-{
-}
-
 void cameraSave(PackStream* stream, CameraDefinition* camera)
 {
     v3Save(stream, &camera->location);
diff --git a/lib_paysages/camera.h b/lib_paysages/camera.h
index 0cf7098..057507d 100644
--- a/lib_paysages/camera.h
+++ b/lib_paysages/camera.h
@@ -9,8 +9,6 @@
 extern "C" {
 #endif
 
-void cameraInit();
-void cameraQuit();
 void cameraSave(PackStream* stream, CameraDefinition* camera);
 void cameraLoad(PackStream* stream, CameraDefinition* camera);
 
diff --git a/lib_paysages/layers.c b/lib_paysages/layers.c
new file mode 100644
index 0000000..d71f441
--- /dev/null
+++ b/lib_paysages/layers.c
@@ -0,0 +1,189 @@
+#include "layers.h"
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define LAYERS_MAX_NAME_LENGTH 50
+
+typedef struct
+{
+    void* definition;
+    char name[LAYERS_MAX_NAME_LENGTH + 1];
+} LayerInfo;
+
+struct Layers {
+    LayerType type;
+    int count;
+    int max_count;
+    void* null_layer;
+    LayerInfo* layers_info;
+};
+
+Layers* layersCreate(LayerType type, int max_layer_count)
+{
+    Layers* result = malloc(sizeof(Layers));
+    
+    result->type = type;
+    result->count = 0;
+    result->max_count = max_layer_count;
+    result->null_layer = type.callback_create();
+    result->layers_info = malloc(sizeof(LayerInfo) * max_layer_count);
+    
+    return result;
+}
+
+void layersDelete(Layers* layers)
+{
+    int i;
+    for (i = 0; i < layers->count; i++)
+    {
+        layers->type.callback_delete(layers->layers_info[i].definition);
+    }
+    
+    free(layers->null_layer);
+    free(layers->layers_info);
+    free(layers);
+}
+
+void layersCopy(Layers* source, Layers* destination)
+{
+    int i;
+    
+    assert(source->type == destination->type);
+    assert(source->max_count == destination->max_count);
+
+    /* TODO Optimize by reusing common layers */
+    while (destination->count > 0)
+    {
+        layersDeleteLayer(destination, 0);
+    }
+    for (i = 0; i < source->count; i++)
+    {
+        layersAddLayer(destination, source->layers_info[i].definition);
+        layersSetName(destination, i, layersGetName(source, i));
+    }
+}
+
+void layersValidate(Layers* layers)
+{
+    int i;
+    
+    for (i = 0; i < layers->count; i++)
+    {
+        layers->type.callback_validate(layers->layers_info[i].definition);
+        layers->layers_info[i].name[LAYERS_MAX_NAME_LENGTH] = '\0';
+    }
+}
+
+void layersSave(PackStream* stream, Layers* layers)
+{
+    int i;
+    
+    packWriteInt(stream, &layers->count);
+    for (i = 0; i < layers->count; i++)
+    {
+        packWriteString(stream, layers->layers_info[i].name, LAYERS_MAX_NAME_LENGTH);
+        layers->type.callback_save(stream, layers->layers_info[i].definition);
+    }
+}
+
+void layersLoad(PackStream* stream, Layers* layers)
+{
+    int i;
+    
+    packReadInt(stream, &layers->count);
+    for (i = 0; i < layers->count; i++)
+    {
+        packReadString(stream, layers->layers_info[i].name, LAYERS_MAX_NAME_LENGTH);
+        layers->type.callback_load(stream, layers->layers_info[i].definition);
+    }
+    layersValidate(layers);
+}
+
+const char* layersGetName(Layers* layers, int layer)
+{
+    if (layer >= 0 && layer < layers->count)
+    {
+        return layers->layers_info[layer].name;
+    }
+    else
+    {
+        return "";
+    }
+}
+
+void layersSetName(Layers* layers, int layer, const char* name)
+{
+    if (layer >= 0 && layer < layers->count)
+    {
+        strncpy(layers->layers_info[layer].name, name, LAYERS_MAX_NAME_LENGTH);
+    }
+}
+
+int layersCount(Layers* layers)
+{
+    return layers->count;
+}
+
+void* layersGetLayer(Layers* layers, int layer)
+{
+    if (layer >= 0 && layer < layers->count)
+    {
+        return layers->layers_info[layer].definition;
+    }
+    else
+    {
+        return layers->null_layer;
+    }
+}
+
+int layersAddLayer(Layers* layers, void* definition)
+{
+    if (layers->count < layers->max_count)
+    {
+        layers->layers_info[layers->count].definition = layers->type.callback_create();
+        if (definition)
+        {
+            layers->type.callback_copy(definition, layers->layers_info[layers->count].definition);
+        }
+        
+        layers->count++;
+        layersSetName(layers, layers->count - 1, "unnamed");
+    }
+    else
+    {
+        return -1;
+    }
+}
+
+void layersDeleteLayer(Layers* layers, int layer)
+{
+    if (layer >= 0 && layer < layers->count)
+    {
+        layers->type.callback_delete(layers->layers_info[layer].definition);
+        if (layers->count > 1 && layer < layers->count - 1)
+        {
+            memmove(layers->layers_info + layer, layers->layers_info + layer + 1, sizeof(LayerInfo) * (layers->count - layer - 1));
+        }
+        layers->count--;
+    }
+}
+
+void layersMove(Layers* layers, int layer, int new_position)
+{
+    if (layer >= 0 && layer < layers->count && new_position != layer && new_position >= 0 && new_position < layers->count)
+    {
+        LayerInfo temp;
+        temp = layers->layers_info[layer];
+        if (new_position > layer)
+        {
+            memmove(layers->layers_info + layer, layers->layers_info + layer + 1, sizeof(LayerInfo) * (new_position - layer));
+        }
+        else
+        {
+            memmove(layers->layers_info + new_position + 1, layers->layers_info + new_position, sizeof(LayerInfo) * (layer - new_position));
+        }
+        layers->layers_info[new_position] = temp;
+    }
+}
diff --git a/lib_paysages/layers.h b/lib_paysages/layers.h
new file mode 100644
index 0000000..13a2384
--- /dev/null
+++ b/lib_paysages/layers.h
@@ -0,0 +1,52 @@
+#ifndef _PAYSAGES_LAYERS_H_
+#define _PAYSAGES_LAYERS_H_
+
+/* Factorized layer management (with names) */
+
+#include "pack.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef void* (*LayerCallbackCreate)();
+typedef void (*LayerCallbackDelete)(void* layer);
+typedef void (*LayerCallbackCopy)(void* source, void* definition);
+typedef void (*LayerCallbackValidate)(void* layer);
+typedef void (*LayerCallbackSave)(PackStream* stream, void* layer);
+typedef void (*LayerCallbackLoad)(PackStream* stream, void* layer);
+    
+typedef struct {
+    LayerCallbackCreate callback_create;
+    LayerCallbackDelete callback_delete;
+    LayerCallbackCopy callback_copy;
+    LayerCallbackValidate callback_validate;
+    LayerCallbackSave callback_save;
+    LayerCallbackLoad callback_load;
+} LayerType;
+
+typedef struct Layers Layers;
+
+Layers* layersCreate(LayerType type, int max_layer_count);
+void layersDelete(Layers* layers);
+
+void layersCopy(Layers* source, Layers* destination);
+void layersValidate(Layers* layers);
+
+void layersSave(PackStream* stream, Layers* layers);
+void layersLoad(PackStream* stream, Layers* layers);
+
+const char* layersGetName(Layers* layers, int layer);
+void layersSetName(Layers* layers, int layer, const char* name);
+
+int layersCount(Layers* layers);
+void* layersGetLayer(Layers* layers, int layer);
+int layersAddLayer(Layers* layers, void* definition);
+void layersDeleteLayer(Layers* layers, int layer);
+void layersMove(Layers* layers, int layer, int new_position);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/lib_paysages/scenery.c b/lib_paysages/scenery.c
index a6a5abc..cbaba5f 100644
--- a/lib_paysages/scenery.c
+++ b/lib_paysages/scenery.c
@@ -24,15 +24,9 @@ static void* _custom_data = NULL;
 void sceneryInit()
 {
     noiseInit();
-    atmosphereInit();
-    cameraInit();
     cloudsInit();
     lightingInit();
-    skyInit();
-    terrainInit();
     texturesInit();
-    vegetationInit();
-    waterInit();
 
     _atmosphere = atmosphereCreateDefinition();
     _camera = cameraCreateDefinition();
@@ -60,15 +54,9 @@ void sceneryQuit()
     vegetationDeleteDefinition(_vegetation);
     waterDeleteDefinition(&_water);
 
-    atmosphereQuit();
-    cameraQuit();
     cloudsQuit();
     lightingQuit();
-    skyQuit();
-    terrainQuit();
     texturesQuit();
-    vegetationQuit();
-    waterQuit();
     noiseQuit();
 }
 
diff --git a/lib_paysages/sky.c b/lib_paysages/sky.c
index 54a8489..cc59e95 100644
--- a/lib_paysages/sky.c
+++ b/lib_paysages/sky.c
@@ -16,14 +16,6 @@
 #define SPHERE_SIZE 1000.0
 
 /******************************** Configuration ********************************/
-void skyInit()
-{
-}
-
-void skyQuit()
-{
-}
-
 void skySave(PackStream* stream, SkyDefinition* definition)
 {
     packWriteInt(stream, (int*)&definition->model);
diff --git a/lib_paysages/sky.h b/lib_paysages/sky.h
index ac6af65..9b41d3b 100644
--- a/lib_paysages/sky.h
+++ b/lib_paysages/sky.h
@@ -39,8 +39,6 @@ typedef struct
     } model_preetham;
 } SkyDefinition;
 
-void skyInit();
-void skyQuit();
 void skySave(PackStream* stream, SkyDefinition* definition);
 void skyLoad(PackStream* stream, SkyDefinition* definition);
 
diff --git a/lib_paysages/terrain.c b/lib_paysages/terrain.c
index 6184d82..db169c4 100644
--- a/lib_paysages/terrain.c
+++ b/lib_paysages/terrain.c
@@ -11,54 +11,26 @@
 #include "textures.h"
 #include "water.h"
 #include "tools.h"
-
-void terrainInit()
-{
-}
-
-void terrainQuit()
-{
-}
+#include "layers.h"
+#include "terraincanvas.h"
 
 void terrainSave(PackStream* stream, TerrainDefinition* definition)
 {
-    int i;
-
     noiseSaveGenerator(stream, definition->height_noise);
     packWriteDouble(stream, &definition->height_factor);
     packWriteDouble(stream, &definition->scaling);
+    layersSave(stream, &definition->canvases);
     packWriteDouble(stream, &definition->shadow_smoothing);
-
-    packWriteInt(stream, &definition->height_modifiers_count);
-    for (i = 0; i < definition->height_modifiers_count; i++)
-    {
-        modifierSave(stream, definition->height_modifiers[i]);
-    }
 }
 
 void terrainLoad(PackStream* stream, TerrainDefinition* definition)
 {
-    int i, n;
-    HeightModifier* modifier;
-
     noiseLoadGenerator(stream, definition->height_noise);
     packReadDouble(stream, &definition->height_factor);
     packReadDouble(stream, &definition->scaling);
+    layersLoad(stream, &definition->canvases);
     packReadDouble(stream, &definition->shadow_smoothing);
 
-    while (definition->height_modifiers_count > 0)
-    {
-        terrainDelModifier(definition, 0);
-    }
-    packReadInt(stream, &n);
-    for (i = 0; i < n; i++)
-    {
-        modifier = modifierCreate();
-        modifierLoad(stream, modifier);
-        terrainAddModifier(definition, modifier);
-        modifierDelete(modifier);
-    }
-
     terrainValidateDefinition(definition);
 }
 
@@ -69,7 +41,7 @@ TerrainDefinition terrainCreateDefinition()
     definition.height_noise = noiseCreateGenerator();
     definition.height_factor = 0.0;
     definition.scaling = 1.0;
-    definition.height_modifiers_count = 0;
+    definition.canvases = layersCreate(terrainCanvasGetLayerType(), 50);
     definition.shadow_smoothing = 0.0;
 
     terrainValidateDefinition(&definition);
@@ -82,10 +54,7 @@ void terrainDeleteDefinition(TerrainDefinition* definition)
     int i;
 
     noiseDeleteGenerator(definition->height_noise);
-    for (i = 0; i < definition->height_modifiers_count; i++)
-    {
-        modifierDelete(definition->height_modifiers[i]);
-    }
+    layersDelete(definition->canvases);
 }
 
 void terrainCopyDefinition(TerrainDefinition* source, TerrainDefinition* destination)
@@ -95,52 +64,19 @@ void terrainCopyDefinition(TerrainDefinition* source, TerrainDefinition* destina
     noiseCopy(source->height_noise, destination->height_noise);
     destination->height_factor = source->height_factor;
     destination->scaling = source->scaling;
+    layersCopy(source->canvases, destination->canvases);
     destination->shadow_smoothing = source->shadow_smoothing;
 
-    for (i = 0; i < destination->height_modifiers_count; i++)
-    {
-        modifierDelete(destination->height_modifiers[i]);
-    }
-    destination->height_modifiers_count = 0;
-
-    for (i = 0; i < source->height_modifiers_count; i++)
-    {
-        terrainAddModifier(destination, source->height_modifiers[i]);
-    }
-
     terrainValidateDefinition(destination);
 }
 
 void terrainValidateDefinition(TerrainDefinition* definition)
 {
+    noiseValidate(definition->height_noise);
+    layersValidate(definition->canvases);
+    
     definition->_max_height = noiseGetMaxValue(definition->height_noise) * definition->height_factor;
-    /* FIXME _max_height depends on modifiers */
-}
-
-int terrainAddModifier(TerrainDefinition* definition, HeightModifier* modifier)
-{
-    if (definition->height_modifiers_count < TERRAIN_MAX_MODIFIERS)
-    {
-        definition->height_modifiers[definition->height_modifiers_count] = modifierCreateCopy(modifier);
-        return definition->height_modifiers_count++;
-    }
-    else
-    {
-        return -1;
-    }
-}
-
-void terrainDelModifier(TerrainDefinition* definition, int modifier_position)
-{
-    if (modifier_position >= 0 && modifier_position < definition->height_modifiers_count)
-    {
-        modifierDelete(definition->height_modifiers[modifier_position]);
-        if (definition->height_modifiers_count > 1 && modifier_position < definition->height_modifiers_count - 1)
-        {
-            memmove(definition->height_modifiers + modifier_position, definition->height_modifiers + modifier_position + 1, sizeof(HeightModifier*) * (definition->height_modifiers_count - modifier_position - 1));
-        }
-        definition->height_modifiers_count--;
-    }
+    /* FIXME _max_height depends on canvases/modifiers */
 }
 
 static inline double _getHeight(TerrainDefinition* definition, double x, double z)
@@ -152,10 +88,7 @@ static inline double _getHeight(TerrainDefinition* definition, double x, double
     location.y = noiseGet2DTotal(definition->height_noise, x / definition->scaling, z / definition->scaling) * definition->height_factor;
     location.z = z;
 
-    for (i = 0; i < definition->height_modifiers_count; i++)
-    {
-        location = modifierApply(definition->height_modifiers[i], location);
-    }
+    /* TODO Apply canvases and modifiers */
 
     return location.y;
 }
@@ -169,10 +102,7 @@ static inline double _getHeightDetail(TerrainDefinition* definition, double x, d
     location.y = noiseGet2DDetail(definition->height_noise, x / definition->scaling, z / definition->scaling, detail / definition->height_factor) * definition->height_factor;
     location.z = z;
 
-    for (i = 0; i < definition->height_modifiers_count; i++)
-    {
-        location = modifierApply(definition->height_modifiers[i], location);
-    }
+    /* TODO Apply canvases and modifiers */
 
     return location.y;
 }
diff --git a/lib_paysages/terrain.h b/lib_paysages/terrain.h
index 9ef08e6..a65f1fa 100644
--- a/lib_paysages/terrain.h
+++ b/lib_paysages/terrain.h
@@ -6,6 +6,7 @@
 #include "noise.h"
 #include "lighting.h"
 #include "pack.h"
+#include "layers.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -18,15 +19,12 @@ typedef struct
     NoiseGenerator* height_noise;
     double height_factor;
     double scaling;
-    int height_modifiers_count;
-    HeightModifier* height_modifiers[TERRAIN_MAX_MODIFIERS];
+    Layers* canvases;
     double shadow_smoothing;
 
     double _max_height;
 } TerrainDefinition;
 
-void terrainInit();
-void terrainQuit();
 void terrainSave(PackStream* stream, TerrainDefinition* definition);
 void terrainLoad(PackStream* stream, TerrainDefinition* definition);
 
@@ -35,9 +33,6 @@ void terrainDeleteDefinition(TerrainDefinition* definition);
 void terrainCopyDefinition(TerrainDefinition* source, TerrainDefinition* destination);
 void terrainValidateDefinition(TerrainDefinition* definition);
 
-int terrainAddModifier(TerrainDefinition* definition, HeightModifier* modifier);
-void terrainDelModifier(TerrainDefinition* definition, int modifier_position);
-
 Color terrainLightFilter(TerrainDefinition* definition, Renderer* renderer, Color light, Vector3 location, Vector3 light_location, Vector3 direction_to_light);
 int terrainProjectRay(TerrainDefinition* definition, Renderer* renderer, Vector3 start, Vector3 direction, Vector3* hit_point, Color* hit_color);
 double terrainGetHeight(TerrainDefinition* definition, double x, double z);
diff --git a/lib_paysages/terraincanvas.c b/lib_paysages/terraincanvas.c
new file mode 100644
index 0000000..c849241
--- /dev/null
+++ b/lib_paysages/terraincanvas.c
@@ -0,0 +1,130 @@
+#include "terraincanvas.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+TerrainCanvas* terrainCanvasCreate()
+{
+    TerrainCanvas* result = malloc(sizeof(TerrainCanvas));
+    
+    result->area.bounded = 1;
+    result->area.location_x = 0.0;
+    result->area.location_z = 0.0;
+    result->area.size_x = 1.0;
+    result->area.size_z = 1.0;
+    result->offset_z = 0.0;
+    result->height_map.data = malloc(sizeof(double));
+    result->height_map.resolution_x = 1;
+    result->height_map.resolution_z = 1;
+    result->height_factor = 1.0;
+    result->detail_noise = noiseCreateGenerator();
+    result->detail_height_factor = 0.1;
+    result->detail_scaling = 1.0;
+    result->mask_mode = TERRAINCANVAS_MASKMODE_SQUARE;
+    result->mask_smoothing = 0.0;
+    
+    return result;
+}
+
+void terrainCanvasDelete(TerrainCanvas* canvas)
+{
+    free(canvas->height_map.data);
+    noiseDeleteGenerator(canvas->detail_noise);
+    free(canvas);
+}
+
+void terrainCanvasCopy(TerrainCanvas* source, TerrainCanvas* destination)
+{
+    destination->area = source->area;
+    destination->offset_z = source->offset_z;
+    destination->height_map.resolution_x = source->height_map.resolution_x;
+    destination->height_map.resolution_z = source->height_map.resolution_z;
+    destination->height_map.data = realloc(destination->height_map.data, sizeof(double) * destination->height_map.resolution_x * destination->height_map.resolution_z);
+    memcpy(destination->height_map.data, source->height_map.data, sizeof(double) * destination->height_map.resolution_x * destination->height_map.resolution_z);
+    destination->height_factor = source->height_factor;
+    noiseCopy(source->detail_noise, destination->detail_noise);
+    destination->detail_height_factor = source->detail_height_factor;
+    destination->detail_scaling = source->detail_scaling;
+    destination->mask_mode = source->mask_mode;
+    destination->mask_smoothing = source->mask_smoothing;
+}
+
+void terrainCanvasValidate(TerrainCanvas* canvas)
+{
+    if (canvas->detail_scaling < 0.00001)
+    {
+        canvas->detail_scaling = 0.00001;
+    }
+    noiseValidate(canvas->detail_noise);
+}
+
+LayerType terrainCanvasGetLayerType()
+{
+    LayerType result;
+    
+    result.callback_create = (LayerCallbackCreate)terrainCanvasCreate;
+    result.callback_delete = (LayerCallbackDelete)terrainCanvasDelete;
+    result.callback_copy = (LayerCallbackCopy)terrainCanvasCopy;
+    result.callback_validate = (LayerCallbackValidate)terrainCanvasValidate;
+    result.callback_save = (LayerCallbackSave)terrainCanvasSave;
+    result.callback_load = (LayerCallbackLoad)terrainCanvasLoad;
+    
+    return result;
+}
+
+void terrainCanvasSave(PackStream* stream, TerrainCanvas* canvas)
+{
+    int i;
+    
+    packWriteInt(stream, &canvas->area.bounded);
+    packWriteDouble(stream, &canvas->area.location_x);
+    packWriteDouble(stream, &canvas->area.location_z);
+    packWriteDouble(stream, &canvas->area.size_x);
+    packWriteDouble(stream, &canvas->area.size_z);
+    packWriteDouble(stream, &canvas->offset_z);
+    packWriteInt(stream, &canvas->height_map.resolution_x);
+    packWriteInt(stream, &canvas->height_map.resolution_z);
+    for (i = 0; i < canvas->height_map.resolution_x * canvas->height_map.resolution_z; i++)
+    {
+        packWriteDouble(stream, &canvas->height_map.data[i]);
+    }
+    packWriteDouble(stream, &canvas->height_factor);
+    noiseSaveGenerator(stream, canvas->detail_noise);
+    packWriteDouble(stream, &canvas->detail_height_factor);
+    packWriteDouble(stream, &canvas->detail_scaling);
+    packWriteInt(stream, &canvas->mask_mode);
+    packWriteDouble(stream, &canvas->mask_smoothing);
+}
+
+void terrainCanvasLoad(PackStream* stream, TerrainCanvas* canvas)
+{
+    int i;
+    
+    packReadInt(stream, &canvas->area.bounded);
+    packReadDouble(stream, &canvas->area.location_x);
+    packReadDouble(stream, &canvas->area.location_z);
+    packReadDouble(stream, &canvas->area.size_x);
+    packReadDouble(stream, &canvas->area.size_z);
+    packReadDouble(stream, &canvas->offset_z);
+    packReadInt(stream, &canvas->height_map.resolution_x);
+    packReadInt(stream, &canvas->height_map.resolution_z);
+    canvas->height_map.data = realloc(canvas->height_map.data, sizeof(double) * canvas->height_map.resolution_x * canvas->height_map.resolution_z);
+    for (i = 0; i < canvas->height_map.resolution_x * canvas->height_map.resolution_z; i++)
+    {
+        packReadDouble(stream, &canvas->height_map.data[i]);
+    }
+    packReadDouble(stream, &canvas->height_factor);
+    noiseLoadGenerator(stream, canvas->detail_noise);
+    packReadDouble(stream, &canvas->detail_height_factor);
+    packReadDouble(stream, &canvas->detail_scaling);
+    packReadInt(stream, &canvas->mask_mode);
+    packReadDouble(stream, &canvas->mask_smoothing);
+}
+
+void terrainCanvasRevertToTerrain(TerrainCanvas* canvas, TerrainDefinition* terrain, int only_masked)
+{
+}
+
+Vector3 terrainCanvasApply(TerrainCanvas* canvas, Vector3 position)
+{
+}
diff --git a/lib_paysages/terraincanvas.h b/lib_paysages/terraincanvas.h
new file mode 100644
index 0000000..a8e45f4
--- /dev/null
+++ b/lib_paysages/terraincanvas.h
@@ -0,0 +1,63 @@
+#ifndef _PAYSAGES_TERRAINCANVAS_H_
+#define _PAYSAGES_TERRAINCANVAS_H_
+
+/* Terrain edition by painting over an area */
+
+#include "pack.h"
+#include "noise.h"
+#include "terrain.h"
+#include "layers.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct
+{
+    int bounded;
+    double location_x;
+    double location_z;
+    double size_x;
+    double size_z;
+} GeoArea;
+
+typedef struct
+{
+    int resolution_x;
+    int resolution_z;
+    double* data;
+} HeightMap;
+
+#define TERRAINCANVAS_MASKMODE_SQUARE 0
+#define TERRAINCANVAS_MASKMODE_CIRCLE 1
+
+typedef struct
+{
+    GeoArea area;
+    double offset_z;
+    HeightMap height_map;
+    double height_factor;
+    NoiseGenerator* detail_noise;
+    double detail_height_factor;
+    double detail_scaling;
+    int mask_mode;
+    double mask_smoothing;
+} TerrainCanvas;
+
+TerrainCanvas* terrainCanvasCreate();
+void terrainCanvasDelete(TerrainCanvas* canvas);
+void terrainCanvasCopy(TerrainCanvas* source, TerrainCanvas* destination);
+void terrainCanvasValidate(TerrainCanvas* canvas);
+LayerType terrainCanvasGetLayerType();
+
+void terrainCanvasSave(PackStream* stream, TerrainCanvas* canvas);
+void terrainCanvasLoad(PackStream* stream, TerrainCanvas* canvas);
+
+void terrainCanvasRevertToTerrain(TerrainCanvas* canvas, TerrainDefinition* terrain, int only_masked);
+Vector3 terrainCanvasApply(TerrainCanvas* canvas, Vector3 position);
+    
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/lib_paysages/vegetation.c b/lib_paysages/vegetation.c
index b529fd5..af8acda 100644
--- a/lib_paysages/vegetation.c
+++ b/lib_paysages/vegetation.c
@@ -7,14 +7,6 @@ struct VegetationDefinition {
     VegetationLayerDefinition layers[MAX_LAYER_COUNT];
 };
 
-void vegetationInit()
-{
-}
-
-void vegetationQuit()
-{
-}
-
 void vegetationSave(PackStream* stream, VegetationDefinition* definition)
 {
 }
diff --git a/lib_paysages/vegetation.h b/lib_paysages/vegetation.h
index 12077c6..d9d6b62 100644
--- a/lib_paysages/vegetation.h
+++ b/lib_paysages/vegetation.h
@@ -18,8 +18,6 @@ typedef struct
 
 typedef struct VegetationDefinition VegetationDefinition;
 
-void vegetationInit();
-void vegetationQuit();
 void vegetationSave(PackStream* stream, VegetationDefinition* definition);
 void vegetationLoad(PackStream* stream, VegetationDefinition* definition);
 
diff --git a/lib_paysages/water.c b/lib_paysages/water.c
index 4804cc8..380d53e 100644
--- a/lib_paysages/water.c
+++ b/lib_paysages/water.c
@@ -10,14 +10,6 @@
 
 #include <math.h>
 
-void waterInit()
-{
-}
-
-void waterQuit()
-{
-}
-
 void waterSave(PackStream* stream, WaterDefinition* definition)
 {
     packWriteDouble(stream, &definition->height);
diff --git a/lib_paysages/water.h b/lib_paysages/water.h
index ed1a071..f358dc3 100644
--- a/lib_paysages/water.h
+++ b/lib_paysages/water.h
@@ -34,8 +34,6 @@ typedef struct
     Color final;
 } WaterResult;
 
-void waterInit();
-void waterQuit();
 void waterSave(PackStream* stream, WaterDefinition* definition);
 void waterLoad(PackStream* stream, WaterDefinition* definition);