diff --git a/demos/demo_macos.h b/demos/demo_macos.h
index a20ef8803..28182dd3d 100644
--- a/demos/demo_macos.h
+++ b/demos/demo_macos.h
@@ -177,6 +177,7 @@ static demo_key demo_key_from_nsevent(id event)
     enum vkey
     {
         kVK_ANSI_A              = 0x00,
+        kVK_ANSI_F              = 0x03,
         kVK_ANSI_W              = 0x0d,
         kVK_ANSI_Equal          = 0x18,
         kVK_ANSI_Minus          = 0x1b,
@@ -199,6 +200,7 @@ static demo_key demo_key_from_nsevent(id event)
     lookup[] =
     {
         {kVK_ANSI_A,            'a'},
+        {kVK_ANSI_F,            'f'},
         {kVK_ANSI_W,            'w'},
         {kVK_ANSI_Equal,        '='},
         {kVK_ANSI_Minus,        '-'},
diff --git a/demos/teapot.c b/demos/teapot.c
index e1cdd911a..f5994c883 100644
--- a/demos/teapot.c
+++ b/demos/teapot.c
@@ -39,7 +39,7 @@ struct teapot_cb_data
 {
     struct demo_matrix mvp_matrix;
     float level;
-    unsigned int wireframe;
+    unsigned int wireframe, flat;
 };
 
 struct demo_text_run
@@ -91,7 +91,7 @@ struct teapot
     unsigned int text_scale;
     float theta, phi;
 
-    bool display_help, wireframe;
+    bool display_help, flat, wireframe;
     struct timeval last_text;
     struct timeval frame_times[16];
     size_t frame_count;
@@ -546,9 +546,10 @@ static void teapot_update_text(struct teapot *teapot, double fps)
         demo_text_draw(text, &amber, 0, -2 * h, "%.2f fps", fps);
     if (teapot->display_help)
     {
-        demo_text_draw(text, &amber, 0, 3 * h, "ESC: Exit");
-        demo_text_draw(text, &amber, 0, 2 * h, " F1: Toggle help");
-        demo_text_draw(text, &amber, 0, 1 * h, "-/+: Tessellation level (%u)", teapot->tessellation_level);
+        demo_text_draw(text, &amber, 0, 4 * h, "ESC: Exit");
+        demo_text_draw(text, &amber, 0, 3 * h, " F1: Toggle help");
+        demo_text_draw(text, &amber, 0, 2 * h, "-/+: Tessellation level (%u)", teapot->tessellation_level);
+        demo_text_draw(text, &amber, 0, 1 * h, "  F: Toggle flat shading (%s)", teapot->flat ? "on" : "off");
         demo_text_draw(text, &amber, 0, 0 * h, "  W: Toggle wireframe (%s)", teapot->wireframe ? "on" : "off");
     }
 
@@ -751,8 +752,7 @@ static void teapot_load_assets(struct teapot *teapot)
     root_signature_desc.NumParameters = 1;
     root_signature_desc.pParameters = root_parameters;
     root_signature_desc.Flags = D3D12_ROOT_SIGNATURE_FLAG_ALLOW_INPUT_ASSEMBLER_INPUT_LAYOUT
-            | D3D12_ROOT_SIGNATURE_FLAG_DENY_VERTEX_SHADER_ROOT_ACCESS
-            | D3D12_ROOT_SIGNATURE_FLAG_DENY_GEOMETRY_SHADER_ROOT_ACCESS;
+            | D3D12_ROOT_SIGNATURE_FLAG_DENY_VERTEX_SHADER_ROOT_ACCESS;
     hr = demo_create_root_signature(teapot->device, &root_signature_desc, &teapot->root_signature);
     assert(SUCCEEDED(hr));
 
@@ -857,6 +857,7 @@ static void teapot_load_assets(struct teapot *teapot)
     teapot_update_mvp(teapot);
     teapot->cb_data->level = teapot->tessellation_level;
     teapot->cb_data->wireframe = teapot->wireframe;
+    teapot->cb_data->flat = teapot->flat;
 
     demo_text_init(&teapot->text, teapot->device, teapot->width, teapot->height, teapot->text_scale);
     teapot_load_mesh(teapot);
@@ -881,6 +882,9 @@ static void teapot_key_press(struct demo_window *window, demo_key key, void *use
             if (teapot->tessellation_level < D3D12_TESSELLATOR_MAX_TESSELLATION_FACTOR)
                 teapot->cb_data->level = ++teapot->tessellation_level;
             break;
+        case 'f':
+            teapot->cb_data->flat = teapot->flat = !teapot->flat;
+            break;
         case 'w':
             teapot->cb_data->wireframe = teapot->wireframe = !teapot->wireframe;
             break;
diff --git a/demos/teapot.hlsl b/demos/teapot.hlsl
index ee6817ead..3a857c81f 100644
--- a/demos/teapot.hlsl
+++ b/demos/teapot.hlsl
@@ -22,7 +22,7 @@ cbuffer teapot_cb : register(b0)
 {
     float4x4 mvp_matrix;
     float level;
-    uint wireframe;
+    uint wireframe, flat;
 };
 
 struct control_point
@@ -166,6 +166,14 @@ void gs_main(triangle struct gs_in i[3], inout TriangleStream<struct ps_in> stre
     v[2].normal = i[2].normal;
     v[2].barycentric = float2(0.0, 0.0);
 
+    if (flat)
+    {
+        n = normalize(cross(i[1].pos - i[0].pos, i[2].pos - i[0].pos));
+        v[0].normal = n;
+        v[1].normal = n;
+        v[2].normal = n;
+    }
+
     stream.Append(v[0]);
     stream.Append(v[1]);
     stream.Append(v[2]);