diff --git a/data/layout.xml b/data/layout.xml
index 5fa1142..3f298ce 100644
--- a/data/layout.xml
+++ b/data/layout.xml
@@ -359,8 +359,8 @@
         </button-custom>
         <button id="btn-undo" width="50" height="100%" margin="0 5 0 0" text="Undo"/>
         <button id="btn-pen" width="50" height="100%" margin="0 0 0 0" text="Pen"/>
-        <button id="btn-line" width="50" height="100%" margin="0 0 0 0" text="Line"/>
         <button id="btn-erase" width="60" height="100%" margin="0 0 0 0" text="Erase"/>
+        <button id="btn-line" width="50" height="100%" margin="0 0 0 0" text="Line"/>
         <button id="btn-cam" width="70" height="100%" margin="0 0 0 0" text="Camera"/>
         <!-- 
         <button-custom id="btn-layer" width="50" height="100%" margin="0 5 0 0" thickness="1" border-color="0 0 0 1" pad="6" align="center" justify="center">
diff --git a/engine/app.cpp b/engine/app.cpp
index e3ef3e0..988a752 100644
--- a/engine/app.cpp
+++ b/engine/app.cpp
@@ -468,41 +468,43 @@ void App::initLayout()
         if (auto* button = layout[main_id]->find<NodeButton>("btn-pen"))
         {
             button->on_click = [this](Node*) {
-                canvas->m_canvas->m_erase = false;
                 layout[main_id]->find<NodeButton>("btn-pen")->set_color(color_button_hlight);
                 layout[main_id]->find<NodeButton>("btn-erase")->set_color(color_button_normal);
                 layout[main_id]->find<NodeButton>("btn-line")->set_color(color_button_normal);
                 layout[main_id]->find<NodeButton>("btn-cam")->set_color(color_button_normal);
+                Canvas::I->m_state = Canvas::kPenState::Draw;
             };
+            layout[main_id]->find<NodeButton>("btn-pen")->set_color(color_button_hlight);
+            Canvas::I->m_state = Canvas::kPenState::Draw;
         }
         if (auto* button = layout[main_id]->find<NodeButton>("btn-erase"))
         {
             button->on_click = [this](Node*) {
-                canvas->m_canvas->m_erase = true;
                 layout[main_id]->find<NodeButton>("btn-pen")->set_color(color_button_normal);
                 layout[main_id]->find<NodeButton>("btn-erase")->set_color(color_button_hlight);
                 layout[main_id]->find<NodeButton>("btn-line")->set_color(color_button_normal);
                 layout[main_id]->find<NodeButton>("btn-cam")->set_color(color_button_normal);
+                Canvas::I->m_state = Canvas::kPenState::Erase;
             };
         }
         if (auto* button = layout[main_id]->find<NodeButton>("btn-line"))
         {
             button->on_click = [this](Node*) {
-                canvas->m_canvas->m_erase = true;
                 layout[main_id]->find<NodeButton>("btn-pen")->set_color(color_button_normal);
                 layout[main_id]->find<NodeButton>("btn-erase")->set_color(color_button_normal);
                 layout[main_id]->find<NodeButton>("btn-line")->set_color(color_button_hlight);
                 layout[main_id]->find<NodeButton>("btn-cam")->set_color(color_button_normal);
+                Canvas::I->m_state = Canvas::kPenState::Line;
             };
         }
         if (auto* button = layout[main_id]->find<NodeButton>("btn-cam"))
         {
             button->on_click = [this](Node*) {
-                canvas->m_canvas->m_erase = true;
                 layout[main_id]->find<NodeButton>("btn-pen")->set_color(color_button_normal);
                 layout[main_id]->find<NodeButton>("btn-erase")->set_color(color_button_normal);
                 layout[main_id]->find<NodeButton>("btn-line")->set_color(color_button_normal);
                 layout[main_id]->find<NodeButton>("btn-cam")->set_color(color_button_hlight);
+                Canvas::I->m_state = Canvas::kPenState::Camera;
             };
         }
         if (auto* button = layout[main_id]->find<NodeButtonCustom>("btn-bucket"))
@@ -513,26 +515,30 @@ void App::initLayout()
         }
         if (auto* button = layout[main_id]->find<NodeButtonCustom>("btn-stroke"))
         {
-            button->on_click = [this](Node*) {
+            button->on_click = [this, button](Node*) {
                 panels->get_child_index(stroke.get()) == -1 ? panels->add_child(stroke) : panels->remove_child(stroke.get());
+                button->set_color(panels->get_child_index(stroke.get()) == -1 ? color_button_normal : color_button_hlight);
             };
         }
         if (auto* button = layout[main_id]->find<NodeButtonCustom>("btn-brush"))
         {
-            button->on_click = [this](Node*) {
+            button->on_click = [this, button](Node*) {
                 panels->get_child_index(brushes.get()) == -1 ? panels->add_child(brushes) : panels->remove_child(brushes.get());
+                button->set_color(panels->get_child_index(brushes.get()) == -1 ? color_button_normal : color_button_hlight);
             };
         }
         if (auto* button = layout[main_id]->find<NodeButtonCustom>("btn-color"))
         {
-            button->on_click = [this](Node*) {
+            button->on_click = [this, button](Node*) {
                 panels->get_child_index(color.get()) == -1 ? panels->add_child(color) : panels->remove_child(color.get());
+                button->set_color(panels->get_child_index(color.get()) == -1 ? color_button_normal : color_button_hlight);
             };
         }
         if (auto* button = layout[main_id]->find<NodeButtonCustom>("btn-layer"))
         {
-            button->on_click = [this](Node*) {
+            button->on_click = [this, button](Node*) {
                 panels->get_child_index(layers.get()) == -1 ? panels->add_child(layers) : panels->remove_child(layers.get());
+                button->set_color(panels->get_child_index(layers.get()) == -1 ? color_button_normal : color_button_hlight);
             };
         }
 
@@ -563,6 +569,7 @@ void App::initLayout()
                     
                     open_dialog->btn_ok->on_click = [this,open_dialog](Node*)
                     {
+                        layers->clear();
                         canvas->m_canvas->project_open(data_path);
                         for (auto& i : canvas->m_canvas->m_order)
                             layers->add_layer(canvas->m_canvas->m_layers[i].m_name.c_str());
diff --git a/engine/canvas.cpp b/engine/canvas.cpp
index 6bbcc1d..2ab2aa5 100644
--- a/engine/canvas.cpp
+++ b/engine/canvas.cpp
@@ -88,7 +88,7 @@ void ui::Canvas::stroke_draw()
         else
         {
             glDisable(GL_BLEND);
-            if (m_erase)
+            if (m_state == kPenState::Erase)
             {
                 ShaderManager::use(ui::kShader::StrokeErase);
                 //ShaderManager::u_vec4(kShaderUniform::Col, m_brush.m_tip_color);
@@ -275,7 +275,7 @@ void ui::Canvas::stroke_commit()
         m_tex2[i].bind();
         m_sampler.bind(0);
         m_sampler_bg.bind(1);
-        if (m_erase)
+        if (m_state == kPenState::Erase)
         {
             ShaderManager::use(ui::kShader::Texture);
         }
@@ -324,7 +324,7 @@ void ui::Canvas::stroke_start(glm::vec2 point, float pressure, const ui::Brush&
         m_dirty_box[i] = glm::vec4(m_width, m_height, 0, 0); // reset bounding box
         m_dirty_face[i] = false;
         
-        if (m_erase)
+        if (m_state == kPenState::Erase)
         {
             m_layers[m_current_layer_idx].m_rtt[i].bindFramebuffer();
             m_tmp[i].bindTexture();
diff --git a/engine/canvas.h b/engine/canvas.h
index 56896cb..d657eca 100644
--- a/engine/canvas.h
+++ b/engine/canvas.h
@@ -40,7 +40,6 @@ class Canvas
     bool m_dirty = false;
 public:
     static Canvas* I;
-    bool m_erase = false;
     bool m_alpha_lock = false;
     glm::mat4 m_mv;
     glm::mat4 m_proj;
@@ -67,6 +66,8 @@ public:
     Sampler m_sampler_mask;
     glm::vec2 m_cam_rot;
     float m_cam_fov = 85;
+    enum class kPenState { Draw, Erase, Line, Camera };
+    kPenState m_state{ kPenState::Draw };
 
     GLuint cube_id;
     RTT m_latlong;
diff --git a/engine/layout.h b/engine/layout.h
index 651cbbc..7acc361 100644
--- a/engine/layout.h
+++ b/engine/layout.h
@@ -845,6 +845,11 @@ public:
         m_color = color_normal;
         m_mouse_ignore = false;
     }
+    void set_color(const glm::vec4& c)
+    {
+        color_normal = c;
+        m_color = color_normal;
+    }
     virtual kEventResult handle_event(Event* e) override
     {
         NodeBorder::handle_event(e);
@@ -1489,6 +1494,11 @@ public:
         if (on_layer_change)
             on_layer_change(this, -1, m_layers_container->get_child_index(m_current_layer));
     }
+    void clear()
+    {
+        m_layers_container->remove_all_children();
+        m_layers.clear();
+    }
 };
 
 class NodeButtonBrush : public NodeButtonCustom
@@ -1771,6 +1781,7 @@ public:
         init_controls();
         if (m_size.x > 0 && m_size.y > 0)
             m_rtt.create(m_size.x, m_size.y);
+        draw_stroke();
     }
     virtual void clear_context() override
     {
@@ -2043,7 +2054,8 @@ public:
             ui::ShaderManager::u_mat4(kShaderUniform::MVP, plane_mvp);
             for (auto layer_index : m_canvas->m_order)
             {
-                if (!(m_canvas->m_erase && m_canvas->m_show_tmp && m_canvas->m_current_layer_idx == layer_index))
+                if (!(m_canvas->m_state == ui::Canvas::kPenState::Erase && 
+                    m_canvas->m_show_tmp && m_canvas->m_current_layer_idx == layer_index))
                 {
                     ui::ShaderManager::u_float(kShaderUniform::Alpha, m_canvas->m_layers[layer_index].m_opacity);
                     m_canvas->m_layers[layer_index].m_rtt[plane_index].bindTexture();
@@ -2130,7 +2142,7 @@ public:
             break;
         case kEventType::KeyDown:
             if (ke->m_key == kKey::KeyE)
-                m_canvas->m_erase = true;
+                m_canvas->m_state = ui::Canvas::kPenState::Erase;
             if (ke->m_key == kKey::KeySpacebar)
                 m_canvas->m_alpha_lock = true;
             if (ke->m_key == kKey::AndroidVolumeUp)
@@ -2140,7 +2152,7 @@ public:
             break;
         case kEventType::KeyUp:
             if (ke->m_key == kKey::KeyE)
-                m_canvas->m_erase = false;
+                m_canvas->m_state = ui::Canvas::kPenState::Draw;
             if (ke->m_key == kKey::KeySpacebar)
                 m_canvas->m_alpha_lock = false;
             break;