node.hpp

// SPDX-License-Identifier: MIT
// Author:  Giovanni Santini
// Mail:    giovanni.santini@proton.me
// Github:  @San7o
 
#pragma once
 
#include <brenta/script.hpp>
#include <brenta/transform.hpp>
 
#include <tenno/memory.hpp>
#include <tenno/vector.hpp>
 
#include <glm/gtc/matrix_transform.hpp>
 
namespace brenta
{
 
class NodeComponent;
  
//
// Node
// ----
//
// Nodes are the highest abstraction to repserent the scene. Each
// node has one parent and can have many children, creating a tree
// or a graph.
//
// When a node updates itself, it also updates its childrens; this
// propagates recursively down the tree. The same happens for drawing.
//
// The actual usefulness of a node cames with its components, which
// provide specialized functionalities to the node. Each node also
// has a lua script that it runs when it updates, to provide a more
// dynamic and simple way to write the Node's logic.
//
class Node
{
public:
 
  friend class Scene;
 
  Transform transform;
  
  Node() = default;
 
  // Update logic (animations, movement, AI...)
  void update(float delta_time);
 
  // Render frame
  void draw();
 
private:
 
  tenno::vector<tenno::shared_ptr<NodeComponent>>  components;
  std::optional<Script>                            script;
 
  std::optional<tenno::weak_ptr<Node>>      parent;
  tenno::vector<tenno::shared_ptr<Node>>    children;
 
  glm::mat4 world_matrix = glm::mat4(1.0f);
 
  void update_world_matrix();
  
};
 
class NodeComponent
{
public:
 
  friend class Scene;
 
  tenno::weak_ptr<Node>     owner;
 
  virtual ~NodeComponent() = default;
  
  virtual void update(float delta_time)            = 0;
  virtual void draw(const glm::mat4& world_matrix) = 0;
 
};
 
} // namespace brenta