diff --git a/src/render/software/CanvasPixelShader.cpp b/src/render/software/CanvasPixelShader.cpp
index ee8b9a9..80468af 100644
--- a/src/render/software/CanvasPixelShader.cpp
+++ b/src/render/software/CanvasPixelShader.cpp
@@ -6,16 +6,18 @@
 #include "CanvasPixel.h"
 #include "CanvasFragment.h"
 #include "Rasterizer.h"
+#include "RenderProgress.h"
 
-CanvasPixelShader::CanvasPixelShader(const SoftwareCanvasRenderer &renderer, CanvasPortion *portion, int chunk_size, int sub_chunk_size, int chunks_x, int chunks_y):
-    renderer(renderer), portion(portion), chunk_size(chunk_size), sub_chunk_size(sub_chunk_size), chunks_x(chunks_x), chunks_y(chunks_y)
+
+CanvasPixelShader::CanvasPixelShader(const SoftwareCanvasRenderer &renderer, CanvasPortion *portion, RenderProgress *progress, int chunk_size, int sub_chunk_size, int chunks_x, int chunks_y):
+    renderer(renderer), portion(portion), progress(progress), chunk_size(chunk_size), sub_chunk_size(sub_chunk_size), chunks_x(chunks_x), chunks_y(chunks_y)
 {
 }
 
 void CanvasPixelShader::processParallelUnit(int unit)
 {
     // Locate the chunk we work on
-    int prev_sub_chunk_size = chunk_size * 2;
+    int prev_sub_chunk_size = sub_chunk_size * 2;
     int chunk_x = unit / chunks_y;
     int chunk_y = unit % chunks_y;
     int base_x = chunk_x * chunk_size;
@@ -29,6 +31,7 @@ void CanvasPixelShader::processParallelUnit(int unit)
     // Iterate on sub-chunks
     for (int x = 0; x < limit_x; x += sub_chunk_size)
     {
+        int done = 0;
         for (int y = 0; y < limit_y; y += sub_chunk_size)
         {
             if (interrupted)
@@ -57,7 +60,10 @@ void CanvasPixelShader::processParallelUnit(int unit)
                         portion->setColor(base_x + x + fx, base_y + y + fy, composite);
                     }
                 }
+
+                done++;
             }
         }
+        progress->add(done);
     }
 }
diff --git a/src/render/software/CanvasPixelShader.h b/src/render/software/CanvasPixelShader.h
index 76a6c75..4fd10e0 100644
--- a/src/render/software/CanvasPixelShader.h
+++ b/src/render/software/CanvasPixelShader.h
@@ -18,13 +18,14 @@ namespace software {
 class CanvasPixelShader: public ParallelWorker
 {
 public:
-    CanvasPixelShader(const SoftwareCanvasRenderer &renderer, CanvasPortion *portion, int chunk_size, int sub_chunk_size, int chunks_x, int chunks_y);
+    CanvasPixelShader(const SoftwareCanvasRenderer &renderer, CanvasPortion *portion, RenderProgress *progress, int chunk_size, int sub_chunk_size, int chunks_x, int chunks_y);
 
     virtual void processParallelUnit(int unit) override;
 
 private:
     const SoftwareCanvasRenderer &renderer;
     CanvasPortion *portion;
+    RenderProgress *progress;
     int chunk_size;
     int sub_chunk_size;
     int chunks_x;
diff --git a/src/render/software/Rasterizer.cpp b/src/render/software/Rasterizer.cpp
index ed8ff8f..227782c 100644
--- a/src/render/software/Rasterizer.cpp
+++ b/src/render/software/Rasterizer.cpp
@@ -5,6 +5,7 @@
 #include "CanvasPortion.h"
 #include "CanvasFragment.h"
 #include "Vector3.h"
+#include "RenderProgress.h"
 
 struct paysages::software::ScanPoint
 {
@@ -31,14 +32,12 @@ struct paysages::software::RenderScanlines
     int right;
 };
 
-Rasterizer::Rasterizer(SoftwareRenderer* renderer, int client_id, const Color &color):
-    renderer(renderer), client_id(client_id)
+Rasterizer::Rasterizer(SoftwareRenderer* renderer, RenderProgress *progress, int client_id, const Color &color):
+    renderer(renderer), progress(progress), client_id(client_id)
 {
     this->color = new Color(color);
 
     interrupted = false;
-    predicted_poly_count = 0;
-    done_poly_count = 0;
 }
 
 Rasterizer::~Rasterizer()
@@ -51,16 +50,6 @@ void Rasterizer::interrupt()
     interrupted = true;
 }
 
-void Rasterizer::addPredictedPolys(int count)
-{
-    predicted_poly_count += count;
-}
-
-void Rasterizer::addDonePolys(int count)
-{
-    done_poly_count += count;
-}
-
 void Rasterizer::pushProjectedTriangle(CanvasPortion *canvas, const Vector3 &pixel1, const Vector3 &pixel2, const Vector3 &pixel3, const Vector3 &location1, const Vector3 &location2, const Vector3 &location3)
 {
     ScanPoint point1, point2, point3;
diff --git a/src/render/software/Rasterizer.h b/src/render/software/Rasterizer.h
index b633bc2..53662d4 100644
--- a/src/render/software/Rasterizer.h
+++ b/src/render/software/Rasterizer.h
@@ -15,19 +15,24 @@ typedef struct RenderScanlines RenderScanlines;
 class SOFTWARESHARED_EXPORT Rasterizer
 {
 public:
-    Rasterizer(SoftwareRenderer *renderer, int client_id, const Color &color);
+    Rasterizer(SoftwareRenderer *renderer, RenderProgress *progress, int client_id, const Color &color);
     virtual ~Rasterizer();
 
     inline SoftwareRenderer *getRenderer() const {return renderer;}
 
-    virtual void rasterizeToCanvas(CanvasPortion* canvas) = 0;
     virtual Color shadeFragment(const CanvasFragment &fragment) const = 0;
     virtual void interrupt();
 
-protected:
-    void addPredictedPolys(int count=1);
-    void addDonePolys(int count=1);
+    /**
+     * Abstract method to prepare for the rasterization process, and return the estimated progress count.
+     */
+    virtual int prepareRasterization() = 0;
+    /**
+     * Abstract method to effectively do the rasterization on a canvas.
+     */
+    virtual void rasterizeToCanvas(CanvasPortion* canvas) = 0;
 
+protected:
     void pushProjectedTriangle(CanvasPortion *canvas, const Vector3 &pixel1, const Vector3 &pixel2, const Vector3 &pixel3, const Vector3 &location1, const Vector3 &location2, const Vector3 &location3);
 
     void pushTriangle(CanvasPortion *canvas, const Vector3 &v1, const Vector3 &v2, const Vector3 &v3);
@@ -37,6 +42,7 @@ protected:
 
     Color* color;
     SoftwareRenderer *renderer;
+    RenderProgress *progress;
     int client_id;
     bool interrupted;
 
@@ -46,9 +52,6 @@ private:
     void pushScanPoint(CanvasPortion *canvas, RenderScanlines *scanlines, ScanPoint *point);
     void pushScanLineEdge(CanvasPortion *canvas, RenderScanlines *scanlines, ScanPoint *point1, ScanPoint *point2);
     void renderScanLines(CanvasPortion *canvas, RenderScanlines *scanlines);
-
-    int predicted_poly_count;
-    int done_poly_count;
 };
 
 }
diff --git a/src/render/software/RenderProgress.cpp b/src/render/software/RenderProgress.cpp
new file mode 100644
index 0000000..73e989a
--- /dev/null
+++ b/src/render/software/RenderProgress.cpp
@@ -0,0 +1,54 @@
+#include "RenderProgress.h"
+
+#include "Mutex.h"
+
+RenderProgress::RenderProgress(int count)
+{
+    lock = new Mutex();
+    global = 0.0;
+    step = 1.0 / (double)count;
+}
+
+paysages::software::RenderProgress::~RenderProgress()
+{
+    delete lock;
+}
+
+void RenderProgress::add(int value)
+{
+    lock->acquire();
+
+    global += step * (double)value;
+
+    lock->release();
+}
+
+void RenderProgress::enterSub(int count)
+{
+    struct RenderSub sub;
+    sub.start = global;
+    sub.end = global + step;
+    sub.count = count;
+    sub.previous_step = step;
+
+    lock->acquire();
+
+    subs.push(sub);
+    step /= (double)count;
+
+    lock->release();
+}
+
+void RenderProgress::exitSub()
+{
+    lock->acquire();
+
+    struct RenderSub sub = subs.top();
+
+    global = sub.end;
+    step = sub.previous_step;
+
+    subs.pop();
+
+    lock->release();
+}
diff --git a/src/render/software/RenderProgress.h b/src/render/software/RenderProgress.h
new file mode 100644
index 0000000..0f58518
--- /dev/null
+++ b/src/render/software/RenderProgress.h
@@ -0,0 +1,43 @@
+#ifndef RENDERPROGRESS_H
+#define RENDERPROGRESS_H
+
+#include "software_global.h"
+
+#include <stack>
+
+namespace paysages {
+namespace software {
+
+struct RenderSub {
+    double start;
+    double end;
+    int count;
+    double previous_step;
+};
+
+/**
+ * Utility to keep track of render progress.
+ */
+class SOFTWARESHARED_EXPORT RenderProgress
+{
+public:
+    RenderProgress(int count=1);
+    ~RenderProgress();
+
+    inline double get() const {return global;}
+
+    void add(int value=1);
+    void enterSub(int count);
+    void exitSub();
+
+private:
+    Mutex *lock;
+    double global;
+    double step;
+    std::stack<RenderSub> subs;
+};
+
+}
+}
+
+#endif // RENDERPROGRESS_H
diff --git a/src/render/software/SkyRasterizer.cpp b/src/render/software/SkyRasterizer.cpp
index 57866ae..0a429f6 100644
--- a/src/render/software/SkyRasterizer.cpp
+++ b/src/render/software/SkyRasterizer.cpp
@@ -8,25 +8,31 @@
 #include "CloudsRenderer.h"
 #include "Rasterizer.h"
 #include "CanvasFragment.h"
+#include "RenderProgress.h"
 
 #define SPHERE_SIZE 20000.0
 
-SkyRasterizer::SkyRasterizer(SoftwareRenderer* renderer, int client_id):
-    Rasterizer(renderer, client_id, Color(0.9, 0.9, 1.0))
+SkyRasterizer::SkyRasterizer(SoftwareRenderer* renderer, RenderProgress *progress, int client_id):
+    Rasterizer(renderer, progress, client_id, Color(0.9, 0.9, 1.0))
 {
 }
 
+int SkyRasterizer::prepareRasterization()
+{
+    res_i = renderer->render_quality * 40;
+    res_j = renderer->render_quality * 20;
+
+    return res_i * res_j;
+}
+
 void SkyRasterizer::rasterizeToCanvas(CanvasPortion* canvas)
 {
-    int res_i, res_j;
     int i, j;
     double step_i, step_j;
     double current_i, current_j;
     Vector3 vertex1, vertex2, vertex3, vertex4;
     Vector3 camera_location, direction;
 
-    res_i = renderer->render_quality * 40;
-    res_j = renderer->render_quality * 20;
     step_i = M_PI * 2.0 / (double)res_i;
     step_j = M_PI / (double)res_j;
 
@@ -68,6 +74,7 @@ void SkyRasterizer::rasterizeToCanvas(CanvasPortion* canvas)
             /* TODO Triangles at poles */
             pushQuad(canvas, vertex1, vertex4, vertex3, vertex2);
         }
+        progress->add(res_i);
     }
 }
 
diff --git a/src/render/software/SkyRasterizer.h b/src/render/software/SkyRasterizer.h
index 39b09ab..dc5a71b 100644
--- a/src/render/software/SkyRasterizer.h
+++ b/src/render/software/SkyRasterizer.h
@@ -11,10 +11,15 @@ namespace software {
 class SOFTWARESHARED_EXPORT SkyRasterizer: public Rasterizer
 {
 public:
-    SkyRasterizer(SoftwareRenderer* renderer, int client_id);
+    SkyRasterizer(SoftwareRenderer* renderer, RenderProgress *progress, int client_id);
 
+    virtual int prepareRasterization() override;
     virtual void rasterizeToCanvas(CanvasPortion* canvas) override;
     virtual Color shadeFragment(const CanvasFragment &fragment) const override;
+
+private:
+    int res_i;
+    int res_j;
 };
 
 }
diff --git a/src/render/software/SoftwareCanvasRenderer.cpp b/src/render/software/SoftwareCanvasRenderer.cpp
index 2a04bb0..8d9f440 100644
--- a/src/render/software/SoftwareCanvasRenderer.cpp
+++ b/src/render/software/SoftwareCanvasRenderer.cpp
@@ -13,6 +13,7 @@
 #include "RenderConfig.h"
 #include "ColorProfile.h"
 #include "CanvasPreview.h"
+#include "RenderProgress.h"
 
 SoftwareCanvasRenderer::SoftwareCanvasRenderer(Scenery *scenery):
     SoftwareRenderer(scenery)
@@ -21,12 +22,12 @@ SoftwareCanvasRenderer::SoftwareCanvasRenderer(Scenery *scenery):
     finished = false;
     interrupted = false;
     canvas = new Canvas();
-    progress = 0.0;
+    progress = new RenderProgress();
     samples = 1;
 
-    rasterizers.push_back(new SkyRasterizer(this, 0));
-    rasterizers.push_back(new WaterRasterizer(this, 1));
-    rasterizers.push_back(new TerrainRasterizer(this, 2));
+    rasterizers.push_back(new SkyRasterizer(this, progress, 0));
+    rasterizers.push_back(new WaterRasterizer(this, progress, 1));
+    rasterizers.push_back(new TerrainRasterizer(this, progress, 2));
 
     current_work = NULL;
 }
@@ -34,6 +35,7 @@ SoftwareCanvasRenderer::SoftwareCanvasRenderer(Scenery *scenery):
 SoftwareCanvasRenderer::~SoftwareCanvasRenderer()
 {
     delete canvas;
+    delete progress;
 
     for (auto &rasterizer: rasterizers)
     {
@@ -41,6 +43,11 @@ SoftwareCanvasRenderer::~SoftwareCanvasRenderer()
     }
 }
 
+double SoftwareCanvasRenderer::getProgress() const
+{
+    return progress->get();
+}
+
 void SoftwareCanvasRenderer::setConfig(const RenderConfig &config)
 {
     if (not started)
@@ -62,7 +69,6 @@ void SoftwareCanvasRenderer::setSize(int width, int height, int samples)
 void SoftwareCanvasRenderer::render()
 {
     started = true;
-    progress = 0.0;
 
     render_camera->setRenderSize(canvas->getWidth(), canvas->getHeight());
 
@@ -71,32 +77,33 @@ void SoftwareCanvasRenderer::render()
     // Iterate portions
     int nx = canvas->getHorizontalPortionCount();
     int ny = canvas->getVerticalPortionCount();
-    int i = 0;
     int n = nx * ny;
+    progress->enterSub(n);
     for (int y = 0; y < ny; y++)
     {
         for (int x = 0; x < nx; x++)
         {
             CanvasPortion *portion = canvas->at(x, y);
 
+            progress->enterSub(2);
+
             if (not interrupted)
             {
-                progress_segment = 0.2 / (double)n;
                 portion->preparePixels();
                 rasterize(portion);
             }
 
             if (not interrupted)
             {
-                progress_segment = 0.8 / (double)n;
                 applyPixelShader(portion);
             }
 
             portion->discardPixels();
-            i++;
-            progress = (double)i / (double)n;
+
+            progress->exitSub();
         }
     }
+    progress->exitSub();
     finished = true;
 }
 
@@ -126,11 +133,18 @@ bool SoftwareCanvasRenderer::saveToDisk(const std::string &filepath) const
 
 void SoftwareCanvasRenderer::rasterize(CanvasPortion *portion)
 {
+    int count = 0;
+    for (auto &rasterizer:rasterizers)
+    {
+        count += rasterizer->prepareRasterization();
+    }
+
+    progress->enterSub(count);
     for (auto &rasterizer:rasterizers)
     {
         rasterizer->rasterizeToCanvas(portion);
-        progress += progress_segment / (double)rasterizers.size();
     }
+    progress->exitSub();
 }
 
 void SoftwareCanvasRenderer::applyPixelShader(CanvasPortion *portion)
@@ -141,14 +155,8 @@ void SoftwareCanvasRenderer::applyPixelShader(CanvasPortion *portion)
     int chunks_y = (portion->getHeight() - 1) / chunk_size + 1;
     int units = chunks_x * chunks_y;
 
-    // Estimate chunks
-    int n = 0;
-    for (int sub_chunk_size = chunk_size; sub_chunk_size >= 1; sub_chunk_size /= 2)
-    {
-        n += chunk_size / sub_chunk_size;
-    }
-
     // Render chunks in parallel
+    progress->enterSub(portion->getWidth() * portion->getHeight());
     for (int sub_chunk_size = chunk_size; sub_chunk_size >= 1; sub_chunk_size /= 2)
     {
         if (interrupted)
@@ -156,12 +164,12 @@ void SoftwareCanvasRenderer::applyPixelShader(CanvasPortion *portion)
             break;
         }
 
-        CanvasPixelShader shader(*this, portion, chunk_size, sub_chunk_size, chunks_x, chunks_y);
+        CanvasPixelShader shader(*this, portion, progress, chunk_size, sub_chunk_size, chunks_x, chunks_y);
         ParallelWork work(&shader, units);
 
         current_work = &work;
         work.perform();
         current_work = NULL;
-        progress += progress_segment * (double)(chunk_size / sub_chunk_size) / (double)n;
     }
+    progress->exitSub();
 }
diff --git a/src/render/software/SoftwareCanvasRenderer.h b/src/render/software/SoftwareCanvasRenderer.h
index df9d339..ef105b2 100644
--- a/src/render/software/SoftwareCanvasRenderer.h
+++ b/src/render/software/SoftwareCanvasRenderer.h
@@ -23,9 +23,13 @@ public:
     virtual ~SoftwareCanvasRenderer();
 
     inline const Canvas *getCanvas() const {return canvas;}
-    inline double getProgress() const {return progress;}
     inline bool isFinished() const {return finished;}
 
+    /**
+     * Get the global rendering progress (0.0-1.0).
+     */
+    double getProgress() const;
+
     /**
      * Set the renderer configuration.
      */
@@ -72,8 +76,7 @@ protected:
     void applyPixelShader(CanvasPortion *portion);
 
 private:
-    double progress;
-    double progress_segment;
+    RenderProgress *progress;
 
     Canvas *canvas;
     int samples;
diff --git a/src/render/software/TerrainRasterizer.cpp b/src/render/software/TerrainRasterizer.cpp
index c66603b..503b259 100644
--- a/src/render/software/TerrainRasterizer.cpp
+++ b/src/render/software/TerrainRasterizer.cpp
@@ -9,9 +9,10 @@
 #include "Scenery.h"
 #include "CanvasPortion.h"
 #include "CanvasFragment.h"
+#include "RenderProgress.h"
 
-TerrainRasterizer::TerrainRasterizer(SoftwareRenderer* renderer, int client_id):
-    Rasterizer(renderer, client_id, Color(1.0, 0.9, 0.9))
+TerrainRasterizer::TerrainRasterizer(SoftwareRenderer* renderer, RenderProgress *progress, int client_id):
+    Rasterizer(renderer, progress, client_id, Color(1.0, 0.9, 0.9))
 {
 }
 
@@ -22,11 +23,6 @@ static inline Vector3 _getPoint(SoftwareRenderer* renderer, double x, double z)
 
 void TerrainRasterizer::tessellateChunk(CanvasPortion* canvas, TerrainChunkInfo* chunk, int detail)
 {
-    if (detail < 1)
-    {
-        return;
-    }
-
     double water_height = renderer->getWaterRenderer()->getHeightInfo().min_height;
 
     double startx = chunk->point_nw.x;
@@ -40,6 +36,7 @@ void TerrainRasterizer::tessellateChunk(CanvasPortion* canvas, TerrainChunkInfo*
         {
             renderQuad(canvas, startx + (double)i * size, startz + (double)j * size, size, water_height);
         }
+        progress->add(detail);
     }
 }
 
@@ -125,12 +122,11 @@ static void _getChunk(SoftwareRenderer* renderer, TerrainRasterizer::TerrainChun
     }
 }
 
-void TerrainRasterizer::getTessellationInfo(CanvasPortion* canvas, bool displaced)
+int TerrainRasterizer::performTessellation(CanvasPortion* canvas, bool displaced)
 {
     TerrainChunkInfo chunk;
-    int chunk_factor, chunk_count, i;
+    int chunk_factor, chunk_count, i, result;
     Vector3 cam = renderer->getCameraLocation(VECTOR_ZERO);
-    double progress;
     double radius_int, radius_ext;
     double base_chunk_size, chunk_size;
 
@@ -141,42 +137,69 @@ void TerrainRasterizer::getTessellationInfo(CanvasPortion* canvas, bool displace
     radius_int = 0.0;
     radius_ext = base_chunk_size;
     chunk_size = base_chunk_size;
-    progress = 0.0;
+    result = 0;
 
     double cx = cam.x - fmod(cam.x, base_chunk_size);
     double cz = cam.z - fmod(cam.x, base_chunk_size);
 
     while (radius_int < 20000.0)
     {
-        progress = radius_int / 20000.0;
         for (i = 0; i < chunk_count - 1; i++)
         {
             _getChunk(renderer, &chunk, cx - radius_ext + chunk_size * i, cz - radius_ext, chunk_size, displaced);
-            processChunk(canvas, &chunk, progress);
+            if (chunk.detail_hint > 0)
+            {
+                result += chunk.detail_hint * chunk.detail_hint;
+                if (canvas)
+                {
+                    processChunk(canvas, &chunk);
+                }
+            }
             if (interrupted)
             {
-                return;
+                return result;
             }
 
             _getChunk(renderer, &chunk, cx + radius_int, cz - radius_ext + chunk_size * i, chunk_size, displaced);
-            processChunk(canvas, &chunk, progress);
+            if (chunk.detail_hint > 0)
+            {
+                result += chunk.detail_hint * chunk.detail_hint;
+                if (canvas)
+                {
+                    processChunk(canvas, &chunk);
+                }
+            }
             if (interrupted)
             {
-                return;
+                return result;
             }
 
             _getChunk(renderer, &chunk, cx + radius_int - chunk_size * i, cz + radius_int, chunk_size, displaced);
-            processChunk(canvas, &chunk, progress);
+            if (chunk.detail_hint > 0)
+            {
+                result += chunk.detail_hint * chunk.detail_hint;
+                if (canvas)
+                {
+                    processChunk(canvas, &chunk);
+                }
+            }
             if (interrupted)
             {
-                return;
+                return result;
             }
 
             _getChunk(renderer, &chunk, cx - radius_ext, cz + radius_int - chunk_size * i, chunk_size, displaced);
-            processChunk(canvas, &chunk, progress);
+            if (chunk.detail_hint > 0)
+            {
+                result += chunk.detail_hint * chunk.detail_hint;
+                if (canvas)
+                {
+                    processChunk(canvas, &chunk);
+                }
+            }
             if (interrupted)
             {
-                return;
+                return result;
             }
         }
 
@@ -190,16 +213,24 @@ void TerrainRasterizer::getTessellationInfo(CanvasPortion* canvas, bool displace
         radius_int = radius_ext;
         radius_ext += chunk_size;
     }
+
+    return result;
 }
 
-void TerrainRasterizer::processChunk(CanvasPortion* canvas, TerrainChunkInfo* chunk, double)
+void TerrainRasterizer::processChunk(CanvasPortion* canvas, TerrainChunkInfo* chunk)
 {
     tessellateChunk(canvas, chunk, chunk->detail_hint);
 }
 
+int TerrainRasterizer::prepareRasterization()
+{
+    // TODO Chunks could be saved and reused in rasterizeToCanvas
+    return performTessellation(NULL, false);
+}
+
 void TerrainRasterizer::rasterizeToCanvas(CanvasPortion *canvas)
 {
-    getTessellationInfo(canvas, false);
+    performTessellation(canvas, false);
 }
 
 Color TerrainRasterizer::shadeFragment(const CanvasFragment &fragment) const
diff --git a/src/render/software/TerrainRasterizer.h b/src/render/software/TerrainRasterizer.h
index 5958355..4a34f2c 100644
--- a/src/render/software/TerrainRasterizer.h
+++ b/src/render/software/TerrainRasterizer.h
@@ -22,19 +22,28 @@ public:
     } TerrainChunkInfo;
 
 public:
-    TerrainRasterizer(SoftwareRenderer* renderer, int client_id);
+    TerrainRasterizer(SoftwareRenderer* renderer, RenderProgress *progress, int client_id);
 
+    virtual int prepareRasterization() override;
+    virtual void rasterizeToCanvas(CanvasPortion* canvas) override;
+    virtual Color shadeFragment(const CanvasFragment &fragment) const override;
+
+private:
     /**
-     * Method called for each chunk tessellated by getTessellationInfo.
+     * Method called for each chunk tessellated by performTessellation.
      */
-    void processChunk(CanvasPortion* canvas, TerrainChunkInfo* chunk, double progress);
+    void processChunk(CanvasPortion* canvas, TerrainChunkInfo* chunk);
 
     /**
      * Tessellate the terrain, calling processChunk for each chunk.
      *
      * The terrain will be broken in chunks, most detailed near the camera.
+     *
+     * Return the number of quads that has been pushed.
+     *
+     * *canvas* may be NULL to only simulate the tessellation.
      */
-    void getTessellationInfo(CanvasPortion* canvas, bool displaced);
+    int performTessellation(CanvasPortion* canvas, bool displaced);
 
     /**
      * Tessellate a terrain chunk, pushing the quads in the render area.
@@ -42,9 +51,6 @@ public:
     void tessellateChunk(CanvasPortion* canvas, TerrainChunkInfo* chunk, int detail);
 
     void renderQuad(CanvasPortion* canvas, double x, double z, double size, double water_height);
-
-    virtual void rasterizeToCanvas(CanvasPortion* canvas) override;
-    virtual Color shadeFragment(const CanvasFragment &fragment) const override;
 };
 
 }
diff --git a/src/render/software/WaterRasterizer.cpp b/src/render/software/WaterRasterizer.cpp
index 16c82b1..ddad775 100644
--- a/src/render/software/WaterRasterizer.cpp
+++ b/src/render/software/WaterRasterizer.cpp
@@ -3,9 +3,10 @@
 #include "SoftwareRenderer.h"
 #include "WaterRenderer.h"
 #include "CanvasFragment.h"
+#include "RenderProgress.h"
 
-WaterRasterizer::WaterRasterizer(SoftwareRenderer* renderer, int client_id):
-    Rasterizer(renderer, client_id, Color(0.9, 0.95, 1.0))
+WaterRasterizer::WaterRasterizer(SoftwareRenderer* renderer, RenderProgress *progress, int client_id):
+    Rasterizer(renderer, progress, client_id, Color(0.9, 0.95, 1.0))
 {
 }
 
@@ -32,9 +33,25 @@ void WaterRasterizer::rasterizeQuad(CanvasPortion* canvas, double x, double z, d
     pushQuad(canvas, v1, v2, v3, v4);
 }
 
+int WaterRasterizer::prepareRasterization()
+{
+    return performTessellation(NULL);
+}
+
 void WaterRasterizer::rasterizeToCanvas(CanvasPortion *canvas)
 {
-    int chunk_factor, chunk_count, i;
+    performTessellation(canvas);
+}
+
+Color WaterRasterizer::shadeFragment(const CanvasFragment &fragment) const
+{
+    Vector3 location = fragment.getLocation();
+    return renderer->getWaterRenderer()->getResult(location.x, location.z).final;
+}
+
+int WaterRasterizer::performTessellation(CanvasPortion *canvas)
+{
+    int chunk_factor, chunk_count, i, result;
     Vector3 cam = renderer->getCameraLocation(VECTOR_ZERO);
     double radius_int, radius_ext, base_chunk_size, chunk_size;
 
@@ -44,6 +61,7 @@ void WaterRasterizer::rasterizeToCanvas(CanvasPortion *canvas)
         base_chunk_size *= 0.5;
     }
 
+    result = 0;
     chunk_factor = 1;
     chunk_count = 2;
     radius_int = 0.0;
@@ -57,15 +75,23 @@ void WaterRasterizer::rasterizeToCanvas(CanvasPortion *canvas)
     {
         if (interrupted)
         {
-            return;
+            return result;
         }
 
         for (i = 0; i < chunk_count - 1; i++)
         {
-            rasterizeQuad(canvas, cx - radius_ext + chunk_size * i, cz - radius_ext, chunk_size);
-            rasterizeQuad(canvas, cx + radius_int, cz - radius_ext + chunk_size * i, chunk_size);
-            rasterizeQuad(canvas, cx + radius_int - chunk_size * i, cz + radius_int, chunk_size);
-            rasterizeQuad(canvas, cx - radius_ext, cz + radius_int - chunk_size * i, chunk_size);
+            result++;
+            if (canvas)
+            {
+                rasterizeQuad(canvas, cx - radius_ext + chunk_size * i, cz - radius_ext, chunk_size);
+                rasterizeQuad(canvas, cx + radius_int, cz - radius_ext + chunk_size * i, chunk_size);
+                rasterizeQuad(canvas, cx + radius_int - chunk_size * i, cz + radius_int, chunk_size);
+                rasterizeQuad(canvas, cx - radius_ext, cz + radius_int - chunk_size * i, chunk_size);
+            }
+        }
+        if (canvas)
+        {
+            progress->add(chunk_count - 1);
         }
 
         if (radius_int > 20.0 && chunk_count % 64 == 0 && (double)chunk_factor < radius_int / 20.0)
@@ -78,10 +104,6 @@ void WaterRasterizer::rasterizeToCanvas(CanvasPortion *canvas)
         radius_int = radius_ext;
         radius_ext += chunk_size;
     }
-}
 
-Color WaterRasterizer::shadeFragment(const CanvasFragment &fragment) const
-{
-    Vector3 location = fragment.getLocation();
-    return renderer->getWaterRenderer()->getResult(location.x, location.z).final;
+    return result;
 }
diff --git a/src/render/software/WaterRasterizer.h b/src/render/software/WaterRasterizer.h
index 4d587ae..4b4807c 100644
--- a/src/render/software/WaterRasterizer.h
+++ b/src/render/software/WaterRasterizer.h
@@ -11,12 +11,16 @@ namespace software {
 class WaterRasterizer: public Rasterizer
 {
 public:
-    WaterRasterizer(SoftwareRenderer* renderer, int client_id);
+    WaterRasterizer(SoftwareRenderer* renderer, RenderProgress *progress, int client_id);
 
     void rasterizeQuad(CanvasPortion* canvas, double x, double z, double size);
 
+    virtual int prepareRasterization() override;
     virtual void rasterizeToCanvas(CanvasPortion* canvas) override;
     virtual Color shadeFragment(const CanvasFragment &fragment) const override;
+
+private:
+    int performTessellation(CanvasPortion* canvas);
 };
 
 }
diff --git a/src/render/software/software.pro b/src/render/software/software.pro
index db1fd25..0bc330a 100644
--- a/src/render/software/software.pro
+++ b/src/render/software/software.pro
@@ -50,7 +50,8 @@ SOURCES += SoftwareRenderer.cpp \
     CanvasPictureWriter.cpp \
     clouds/CloudModelAltoCumulus.cpp \
     clouds/CloudModelCirrus.cpp \
-    clouds/CloudModelCumuloNimbus.cpp
+    clouds/CloudModelCumuloNimbus.cpp \
+    RenderProgress.cpp
 
 HEADERS += SoftwareRenderer.h\
         software_global.h \
@@ -90,7 +91,8 @@ HEADERS += SoftwareRenderer.h\
     CanvasPictureWriter.h \
     clouds/CloudModelAltoCumulus.h \
     clouds/CloudModelCirrus.h \
-    clouds/CloudModelCumuloNimbus.h
+    clouds/CloudModelCumuloNimbus.h \
+    RenderProgress.h
 
 unix:!symbian {
     maemo5 {
diff --git a/src/render/software/software_global.h b/src/render/software/software_global.h
index 637b85d..cce6d84 100644
--- a/src/render/software/software_global.h
+++ b/src/render/software/software_global.h
@@ -16,6 +16,7 @@ namespace software {
     class SoftwareRenderer;
     class SoftwareCanvasRenderer;
     class RenderConfig;
+    class RenderProgress;
 
     class FluidMediumManager;
     class FluidMediumInterface;
diff --git a/src/tests/RenderProgress_Test.cpp b/src/tests/RenderProgress_Test.cpp
new file mode 100644
index 0000000..f929f97
--- /dev/null
+++ b/src/tests/RenderProgress_Test.cpp
@@ -0,0 +1,33 @@
+#include "BaseTestCase.h"
+
+#include "RenderProgress.h"
+
+TEST(RenderProgress, RecursiveSections)
+{
+    RenderProgress progress(2);
+    EXPECT_DOUBLE_EQ(0.0, progress.get());
+
+    progress.enterSub(5);
+    EXPECT_DOUBLE_EQ(0.0, progress.get());
+
+    progress.add();
+    EXPECT_DOUBLE_EQ(0.1, progress.get());
+
+    progress.add(2);
+    EXPECT_DOUBLE_EQ(0.3, progress.get());
+
+    progress.enterSub(4);
+    EXPECT_DOUBLE_EQ(0.3, progress.get());
+
+    progress.add(1);
+    EXPECT_DOUBLE_EQ(0.325, progress.get());
+
+    progress.exitSub();
+    EXPECT_DOUBLE_EQ(0.4, progress.get());
+
+    progress.exitSub();
+    EXPECT_DOUBLE_EQ(0.5, progress.get());
+
+    progress.add(1);
+    EXPECT_DOUBLE_EQ(1.0, progress.get());
+}
diff --git a/src/tests/tests.pro b/src/tests/tests.pro
index a1e661e..ce4b6a1 100644
--- a/src/tests/tests.pro
+++ b/src/tests/tests.pro
@@ -26,7 +26,8 @@ SOURCES += main.cpp \
     DefinitionNode_Test.cpp \
     FloatNode_Test.cpp \
     DiffManager_Test.cpp \
-    ColorHSL_Test.cpp
+    ColorHSL_Test.cpp \
+    RenderProgress_Test.cpp
 
 HEADERS += \
     BaseTestCase.h