added range loop based layout nodes traversal

engine/app.cpp

@@ -126,23 +126,18 @@ void App::update(float dt)
     shader_color.u_vec4("col", { .3f, .3f, .3f, 1 });
 
     glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
-    std::stack<Node*> nodes;
-    Node* current = &layout;
-    nodes.push(current);
     glEnable(GL_SCISSOR_TEST);
-    while (current)
+    for (auto& n : layout)
     {
-        nodes.pop();
-
         glm::mat4 pivot = glm::translate(glm::vec3(.5f, .5f, 0.f));
-        glm::mat4 scale = glm::scale(glm::vec3(current->m_size, 1.f));
-        glm::mat4 pos = glm::translate(glm::vec3(current->m_pos, 0));
+        glm::mat4 scale = glm::scale(glm::vec3(n.m_size, 1.f));
+        glm::mat4 pos = glm::translate(glm::vec3(n.m_pos, 0));
         auto mvp = proj * pos * scale * pivot;
 
-        auto box = current->m_clip;
+        auto box = n.m_clip;
         glScissor(box.x, height - box.y - box.w, box.z, box.w);
 
-        shader_color.u_vec4("col", current->color);
+        shader_color.u_vec4("col", n.color);
         shader_color.use();
         shader_color.u_mat4("mvp", mvp);
         plane.draw_fill();
@@ -151,33 +146,10 @@ void App::update(float dt)
         shader_color.use();
         shader_color.u_mat4("mvp", mvp);
         plane.draw_stroke();
-
-        for (auto& c : current->children)
-            nodes.push(&c);
-        current = nodes.size() ? nodes.top() : nullptr;
     }
     glDisable(GL_SCISSOR_TEST); 
     tex.unbind();
     sampler.unbind();
-
-    //glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
-    //shader_color.use();
-    //shader_color.u_mat4("mvp", proj * glm::translate(glm::vec3{width/2, height/2, 0.f}) * glm::scale(glm::vec3(8)));
-    //shader_color.u_vec4("col", {1, 1, 1, 1});
-    
-    //glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
-    //tex.bind();
-    //shader.use(); 
-    //shader.u_mat4("mvp", proj * glm::translate(glm::vec3{ width / 2, height / 2, 0.f }) * glm::scale(glm::vec3(8)));
-    //shader.u_int("tex", 0);
-    //circle3.draw_fill();
-
-    //glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
-    //shader_color.use();
-    //shader_color.u_mat4("mvp", proj * glm::translate(glm::vec3{width/2, height/2, 0.f}) * glm::scale(glm::vec3(8)));
-    //shader_color.u_vec4("col", {1, 1, 1, 1});
-    //glLineWidth(2);
-    //circle3.draw_fill();
 }
 
 void App::resize(float w, float h)

engine/layout.h

@@ -168,4 +168,37 @@ public:
     void load(const char* path);
     void load_internal(const tinyxml2::XMLElement* x_node);
     void reload();
+
+    class iterator
+    {
+        std::stack<Node*> m_nodes;
+        Node* m_current;
+    public:
+        iterator(Node* root)
+        {
+            m_current = root;
+            if (root)
+                m_nodes.push(root);
+        }
+        iterator& operator++() 
+        { 
+            m_nodes.pop();
+            for (auto& c : m_current->children)
+                m_nodes.push(&c);
+            m_current = m_nodes.size() ? m_nodes.top() : nullptr;
+            return *this;
+        }
+        Node& operator*() { return *m_current; }
+        Node* operator->() { return m_current; }
+        bool operator==(const iterator& rhs) { return m_current == rhs.m_current; }
+        bool operator!=(const iterator& rhs) { return m_current != rhs.m_current; }
+    };
+    iterator begin()
+    {
+        return this;
+    }
+    iterator end()
+    {
+        return nullptr;
+    }
 };