diff --git a/src/render/software/CloudsRenderer.cpp b/src/render/software/CloudsRenderer.cpp
index b8ee363..2159638 100644
--- a/src/render/software/CloudsRenderer.cpp
+++ b/src/render/software/CloudsRenderer.cpp
@@ -10,6 +10,7 @@
 
 #include "clouds/BaseCloudsModel.h"
 #include "clouds/CloudModelAltoCumulus.h"
+#include "clouds/CloudModelCirrus.h"
 #include "clouds/CloudModelStratoCumulus.h"
 
 CloudsRenderer::CloudsRenderer(SoftwareRenderer* parent):
@@ -76,9 +77,11 @@ void CloudsRenderer::update()
         case CloudLayerDefinition::CUMULONIMBUS:
         case CloudLayerDefinition::CIRROCUMULUS:
         case CloudLayerDefinition::CIRROSTRATUS:
-        case CloudLayerDefinition::CIRRUS:
             model = new BaseCloudsModel(layer);
             break;
+        case CloudLayerDefinition::CIRRUS:
+            model = new CloudModelCirrus(layer);
+            break;
         }
 
         layer_models.push_back(model);
diff --git a/src/render/software/clouds/CloudModelCirrus.cpp b/src/render/software/clouds/CloudModelCirrus.cpp
new file mode 100644
index 0000000..b6c8078
--- /dev/null
+++ b/src/render/software/clouds/CloudModelCirrus.cpp
@@ -0,0 +1,62 @@
+#include "CloudModelCirrus.h"
+
+#include "NoiseGenerator.h"
+#include "Vector3.h"
+#include "CloudLayerDefinition.h"
+
+CloudModelCirrus::CloudModelCirrus(CloudLayerDefinition* layer):
+    BaseCloudsModel(layer)
+{
+    noise = new NoiseGenerator();
+}
+
+CloudModelCirrus::~CloudModelCirrus()
+{
+    delete noise;
+}
+
+void CloudModelCirrus::update()
+{
+    noise->clearLevels();
+    noise->addLevelSimple(1.0, -1.0, 1.0);
+    noise->addLevelSimple(1.0 / 6.0, -0.6, 0.6);
+    noise->addLevelSimple(1.0 / 10.0, -0.15, 0.15);
+    noise->addLevelSimple(1.0 / 20.0, -0.09, 0.09);
+    noise->addLevelSimple(1.0 / 40.0, -0.06, 0.06);
+    noise->addLevelSimple(1.0 / 120.0, -0.03, 0.03);
+    noise->addLevelSimple(1.0 / 300.0, -0.01, 0.01);
+    noise->normalizeAmplitude(-4.0, 3.0, 0);
+    noise->setState(layer->getNoiseState());
+}
+
+void CloudModelCirrus::getAltitudeRange(double *min_altitude, double *max_altitude) const
+{
+    *min_altitude = 45.0 + 20.0 * layer->altitude;
+    *max_altitude = *min_altitude + 20.0 * layer->scaling;
+}
+
+double CloudModelCirrus::getDensity(const Vector3 &location) const
+{
+    double val;
+    double min_altitude, max_altitude;
+    double noise_scaling = 30.0 * layer->scaling;
+
+    getAltitudeRange(&min_altitude, &max_altitude);
+
+    if (location.y < min_altitude || location.y > max_altitude)
+    {
+        return 0.0;
+    }
+    else
+    {
+        double x = 0.03 * location.x / noise_scaling;
+        double y = (location.y - min_altitude) / noise_scaling;
+        double z = 0.03 * location.z / noise_scaling;
+
+        //double coverage = layer->coverage * layer->_coverage_by_altitude->getValue((position.y - layer->altitude) / layer->scaling);
+        double coverage = layer->coverage;
+
+        val = 0.6 * noise->get3DTotal(x, y, z);
+        return val - 1.1 + coverage;
+    }
+}
diff --git a/src/render/software/clouds/CloudModelCirrus.h b/src/render/software/clouds/CloudModelCirrus.h
new file mode 100644
index 0000000..5cdfcc4
--- /dev/null
+++ b/src/render/software/clouds/CloudModelCirrus.h
@@ -0,0 +1,29 @@
+#ifndef CLOUDMODELCIRRUS_H
+#define CLOUDMODELCIRRUS_H
+
+#include "../software_global.h"
+
+#include "BaseCloudsModel.h"
+
+namespace paysages {
+namespace software {
+
+class CloudModelCirrus : public BaseCloudsModel
+{
+public:
+    CloudModelCirrus(CloudLayerDefinition* layer);
+    virtual ~CloudModelCirrus();
+
+    virtual void update() override;
+
+    virtual void getAltitudeRange(double *min_altitude, double *max_altitude) const override;
+    virtual double getDensity(const Vector3 &location) const override;
+
+private:
+    NoiseGenerator* noise;
+};
+
+}
+}
+
+#endif // CLOUDMODELCIRRUS_H
diff --git a/src/render/software/software.pro b/src/render/software/software.pro
index f5afcfe..959a4c8 100644
--- a/src/render/software/software.pro
+++ b/src/render/software/software.pro
@@ -38,7 +38,8 @@ SOURCES += SoftwareRenderer.cpp \
     RayCastingManager.cpp \
     NightSky.cpp \
     TerrainRayWalker.cpp \
-    clouds/CloudModelAltoCumulus.cpp
+    clouds/CloudModelAltoCumulus.cpp \
+    clouds/CloudModelCirrus.cpp
 
 HEADERS += SoftwareRenderer.h\
         software_global.h \
@@ -66,7 +67,8 @@ HEADERS += SoftwareRenderer.h\
     RayCastingManager.h \
     NightSky.h \
     TerrainRayWalker.h \
-    clouds/CloudModelAltoCumulus.h
+    clouds/CloudModelAltoCumulus.h \
+    clouds/CloudModelCirrus.h
 
 unix:!symbian {
     maemo5 {