lazy stroke preview rendering

src/app.cpp

@@ -590,8 +590,6 @@ void App::update(float dt)
         {
             auto box = n->m_clip_uncut;
             Node* p = n->m_parent;
-            if (dynamic_cast<NodeBrushPresetItem*>(n))
-                p = p;
             while (p)
             {
                 float pt = YGNodeLayoutGetPadding(p->y_node, YGEdgeTop);
@@ -607,7 +605,21 @@ void App::update(float dt)
             //auto box = n->m_clip;
             //glm::ivec4 c = glm::vec4((int)box.x - 1, (int)(height / zoom - box.y - box.w) - 1, (int)box.z + 2, (int)box.w + 2) * zoom;
             if (box.z <= 0.f || box.w <= 0.f)
+            {
+                if (n->m_on_screen)
+                {
+                    if (dynamic_cast<NodeStrokePreview*>(n))
+                        p = p;
+                    n->handle_on_screen(true, false);
+                    n->m_on_screen = false;
+                }
                 return false;
+            }
+            if (!n->m_on_screen)
+            {
+                n->handle_on_screen(false, true);
+                n->m_on_screen = true;
+            }
             glm::ivec4 c = glm::vec4((int)box.x, (int)(height / zoom - box.y - box.w), (int)box.z, (int)box.w) * zoom;
             glScissor(c.x + off_x, c.y + off_y, c.z, c.w);
             n->draw();

src/node.cpp

@@ -63,7 +63,7 @@ void Node::watch(std::function<bool(Node*)> observer)
     {
         for (auto& c : m_children)
         {
-            if (!glm::any(glm::lessThanEqual(zw(c->m_clip), { 0, 0 })))
+            //if (!glm::any(glm::lessThanEqual(zw(c->m_clip), { 0, 0 })))
                 c->watch(observer);
         }
     }
@@ -268,6 +268,21 @@ void Node::handle_resize(glm::vec2 old_size, glm::vec2 new_size)
 
 }
 
+void Node::handle_on_screen(bool old_visibility, bool new_visibility)
+{
+    if (new_visibility == false)
+    {
+        for (auto& c : m_children)
+        {
+            if (c->m_on_screen)
+            {
+                c->handle_on_screen(true, false);
+                c->m_on_screen = false;
+            }
+        }
+    }
+}
+
 void Node::handle_parent_resize(glm::vec2 old_size, glm::vec2 new_size)
 {
 

src/node.h

@@ -132,6 +132,8 @@ public:
     glm::vec4 m_clip_uncut{ 0, 0, 0, 0 };
     std::string m_name;
     bool m_display = true;
+    // it's actually rendering
+    bool m_on_screen = false;
 
     Node(const Node&) = delete;
     Node& operator=(const Node&) = delete;
@@ -251,6 +253,7 @@ public:
     virtual kEventResult on_event(Event* e);
     virtual kEventResult handle_event(Event* e);
     virtual void handle_resize(glm::vec2 old_size, glm::vec2 new_size);
+    virtual void handle_on_screen(bool old_visibility, bool new_visibility);
     virtual void handle_parent_resize(glm::vec2 old_size, glm::vec2 new_size);
     virtual void create();
     virtual void init();

src/node_panel_brush.h

@@ -37,20 +37,6 @@ class NodePanelBrush : public Node
     NodeButtonCustom* m_btn_down;
     NodeButtonCustom* m_btn_remove;
     bool m_interacted = false;
-    struct header_t {
-        char magic[5]{ 'P', 'P', 'B', 'R', 0 };
-        uint16_t version = 0;
-        uint16_t build = g_version_build;
-        uint16_t brushes = 0;
-        uint16_t deleted = 0;
-    };
-    struct item_t {
-        int m_name_len = 0;
-        int m_high_len = 0;
-        int m_thumb_len = 0;
-        bool m_deleted = false;
-        bool m_user_brush = false;
-    };
 public:
     NodeScroll* m_container;
     std::string m_dir_name;
@@ -94,12 +80,6 @@ class NodePanelBrushPreset : public Node
     NodeButtonCustom* m_btn_down;
     NodeButtonCustom* m_btn_delete;
     NodeButtonCustom* m_btn_save;
-    struct header_t {
-        char magic[5]{ 'P', 'P', 'P', 'R', 0 };
-        uint16_t version = 0;
-        uint16_t count = 0;
-    };
-
 public:
     Node* m_container;
     std::function<void(Node* target, std::shared_ptr<Brush>& brush)> on_brush_changed;

src/node_stroke_preview.cpp

@@ -38,6 +38,8 @@ void NodeStrokePreview::empty_queue()
     s_queue.q.clear();
 }
 
+int NodeStrokePreview::instances = 0;
+
 Node* NodeStrokePreview::clone_instantiate() const
 {
     return new NodeStrokePreview();
@@ -271,7 +273,10 @@ void NodeStrokePreview::draw_stroke_immediate()
     m_sampler_linear.bind(4);
 
     const auto& b = m_brush;
-    
+
+    Stroke m_stroke;
+    Stroke m_dual_stroke;
+
     m_stroke.m_filter_points = false;
     m_stroke.m_max_size = m_max_size > 0 ? m_max_size : m_size.y * .75f;
     m_stroke.m_camera.fov = Canvas::I->m_cam_fov;
@@ -518,10 +523,13 @@ void NodeStrokePreview::draw_stroke()
                     node->m_brush->preload();
 
                     node->async_start();
+
                     gl_state gl;
                     gl.save();
 
-                    auto new_size = node->m_tex_preview.size();
+                    auto new_size = node->m_preview_size;
+                    if (!node->m_tex_preview.ready() || node->m_tex_preview.size() != new_size)
+                        node->m_tex_preview.create((int)new_size.x, (int)new_size.y);
                     if (m_tex.size() != new_size)
                     {
                         m_rtt.create((int)new_size.x, (int)new_size.y);
@@ -558,7 +566,6 @@ void NodeStrokePreview::draw_stroke()
 
 void NodeStrokePreview::draw()
 {
-    //glEnable(GL_BLEND);
     ShaderManager::use(kShader::Texture);
     ShaderManager::u_mat4(kShaderUniform::MVP, m_mvp);
     ShaderManager::u_int(kShaderUniform::Tex, 0);
@@ -574,11 +581,10 @@ void NodeStrokePreview::handle_resize(glm::vec2 old_size, glm::vec2 new_size)
     if (m_tex_preview.size() == new_size || !m_brush)
         return;
 
-    new_size *= root()->m_zoom;
+    m_preview_size = new_size * root()->m_zoom;
 
-    m_tex_preview.create((int)new_size.x, (int)new_size.y);
+    if (m_on_screen)
-
+        draw_stroke();
-    draw_stroke();
 }
 
 void NodeStrokePreview::destroy_immediate()
@@ -586,3 +592,17 @@ void NodeStrokePreview::destroy_immediate()
     Node::destroy_immediate();
     m_tex_preview.destroy();
 }
+
+void NodeStrokePreview::handle_on_screen(bool old_visibility, bool new_visibility)
+{
+    parent::handle_on_screen(old_visibility, new_visibility);
+    if (new_visibility)
+    {
+        draw_stroke();
+    }
+    else
+    {
+        s_queue.Remove(std::static_pointer_cast<NodeStrokePreview>(shared_from_this()));
+        m_tex_preview.destroy();
+    }
+}

src/node_stroke_preview.h

@@ -26,6 +26,7 @@ class NodeStrokePreview : public NodeBorder
     static DynamicShape m_brush_shape;
     Texture2D m_tex_preview;
 public:
+    using parent = NodeBorder;
     static std::atomic_int s_instances;
     static std::atomic_bool s_running;
     static std::thread s_renderer;
@@ -33,11 +34,8 @@ public:
     static void terminate_renderer();
     static void empty_queue();
     std::shared_ptr<Brush> m_brush;
-    std::shared_ptr<Brush> m_dual_brush;
     bool m_draw_first = false;
-    Stroke m_stroke;
+    glm::vec2 m_preview_size = { 0, 0 };
-    Stroke m_dual_stroke;
-    std::vector<glm::vec2> m_bez_points;
     float m_min_flow = 0.f;
     float m_max_size = 0.f;
     float m_pad_override = NAN;
@@ -57,4 +55,5 @@ public:
     virtual void draw() override;
     virtual void handle_resize(glm::vec2 old_size, glm::vec2 new_size) override;
     virtual void destroy_immediate() override;
+    virtual void handle_on_screen(bool old_visibility, bool new_visibility) override;
 };

src/util.h

@@ -198,6 +198,14 @@ public:
         }
         get_cv.notify_one();
     }
+    void Remove(T pkt)
+    {
+        std::unique_lock<std::mutex> lock(mutex);
+        auto it = std::find_if(q.begin(), q.end(), [&pkt](auto const& x) { return x.first == pkt; });
+        if (it != q.end())
+            q.erase(it);
+        if (Max > 0) post_cv.notify_all();
+    }
     T Get()
     {
         static T emptyT{};