diff --git a/examples/TinyRenderer/TinyRenderer.cpp b/examples/TinyRenderer/TinyRenderer.cpp
index db7bcbb35..5930151a4 100644
--- a/examples/TinyRenderer/TinyRenderer.cpp
+++ b/examples/TinyRenderer/TinyRenderer.cpp
@@ -91,7 +91,8 @@ struct Shader : public IShader {
     mat<4,3,float> varying_tri_light_view;
     mat<3,3,float> varying_nrm; // normal per vertex to be interpolated by FS
 	mat<4,3,float> world_tri; // model triangle coordinates in the world space used for backface culling, written by VS
-    
+   
+
     Shader(Model* model, Vec3f light_dir_local, Vec3f light_color, Matrix& modelView, Matrix& lightModelView, Matrix& projectionMat, Matrix& modelMat, Matrix& viewportMat, Vec3f localScaling, const Vec4f& colorRGBA, int width, int height, b3AlignedObjectArray<float>* shadowBuffer, float ambient_coefficient=0.6, float diffuse_coefficient=0.35, float specular_coefficient=0.05)
     :m_model(model),
     m_light_dir_local(light_dir_local),
@@ -112,6 +113,9 @@ struct Shader : public IShader {
     m_height(height)
    
     {
+		m_nearPlane = m_projectionMat.col(3)[2]/(m_projectionMat.col(2)[2]-1);
+		m_farPlane = m_projectionMat.col(3)[2]/(m_projectionMat.col(2)[2]+1);
+		//printf("near=%f, far=%f\n", m_nearPlane, m_farPlane);
         m_invModelMat = m_modelMat.invert_transpose();
 		m_projectionModelViewMat = m_projectionMat*m_modelView1;
 		m_projectionLightViewMat = m_projectionMat*m_lightModelView;
@@ -576,7 +580,7 @@ void TinyRenderer::renderObjectDepth(TinyRenderObjectData& renderData)
         Vec3f localScaling(renderData.m_localScaling[0],renderData.m_localScaling[1],renderData.m_localScaling[2]);
         
         DepthShader shader(model, lightModelViewMatrix, lightViewProjectionMatrix,renderData.m_modelMatrix, localScaling, light_distance);
-        
+        shader.m_farPlane=1e30;
         for (int i=0; i<model->nfaces(); i++)
         {
             for (int j=0; j<3; j++) {
diff --git a/examples/TinyRenderer/our_gl.cpp b/examples/TinyRenderer/our_gl.cpp
index ea570386d..a050eda39 100644
--- a/examples/TinyRenderer/our_gl.cpp
+++ b/examples/TinyRenderer/our_gl.cpp
@@ -180,6 +180,9 @@ void triangle(mat<4,3,float> &clipc, IShader &shader, TGAImage &image, float *zb
 				zbuffer[P.x+P.y*image.get_width()]>frag_depth) 
 				continue;
             bool discard = shader.fragment(bc_clip, color);
+			if (frag_depth<-shader.m_farPlane)
+				discard=true;
+
             if (!discard) {
                 zbuffer[P.x+P.y*image.get_width()] = frag_depth;
                 if (segmentationMaskBuffer)
diff --git a/examples/TinyRenderer/our_gl.h b/examples/TinyRenderer/our_gl.h
index 17403764c..6a18cf1ae 100644
--- a/examples/TinyRenderer/our_gl.h
+++ b/examples/TinyRenderer/our_gl.h
@@ -11,6 +11,8 @@ Matrix projection(float coeff=0.f); // coeff = -1/c
 Matrix lookat(Vec3f eye, Vec3f center, Vec3f up);
 
 struct IShader {
+	 float m_nearPlane;
+	float m_farPlane;
     virtual ~IShader();
     virtual Vec4f vertex(int iface, int nthvert) = 0;
     virtual bool fragment(Vec3f bar, TGAColor &color) = 0;
diff --git a/examples/pybullet/pybullet.c b/examples/pybullet/pybullet.c
index e70395e7e..788bd151e 100644
--- a/examples/pybullet/pybullet.c
+++ b/examples/pybullet/pybullet.c
@@ -6463,7 +6463,7 @@ initpybullet(void)
 	SpamError = PyErr_NewException("pybullet.error", NULL, NULL);
 	Py_INCREF(SpamError);
 	PyModule_AddObject(m, "error", SpamError);
-
+	printf("pybullet build time: %s %s\n", __DATE__,__TIME__);
 		
 	Py_AtExit( b3pybulletExitFunc );