551455-graphics-programming-2526-the-repo-Zyb3rWolfi/TheRepo/TheLabs/SceneNode.cs

using OpenTK.Mathematics;
using System.Collections.Generic;

namespace TheLabs;

public class SceneNode
{
    public RenderObject? RenderObject;
    
    public List<SceneNode> Children = new List<SceneNode>();
    
    public Vector3 Position = Vector3.Zero;
    public Quaternion Rotation = Quaternion.Identity;
    public Vector3 Scale = Vector3.One;
    
    public SceneNode(RenderObject? renderObject = null)
    {
        RenderObject = renderObject;
    }
    
    public void AddChild(SceneNode child)
    {
        Children.Add(child);
    }

    public void Draw(Matrix4 view, Matrix4 projection, Matrix4 parentTransform, Lighting light)
    {
        Matrix4 localTransform = Matrix4.CreateScale(Scale) * Matrix4.CreateFromQuaternion(Rotation) * Matrix4.CreateTranslation(Position);
        Matrix4 globalTransform = localTransform * parentTransform;

        if (RenderObject != null)
        {
            RenderObject.Position = Vector3.Zero;
            RenderObject.Rotation = Quaternion.Identity;
            RenderObject.Scale = Vector3.One;
            
            RenderObject.Draw(view, projection, light);
        }

        foreach (var child in Children)
        {
            child.Draw(view, projection, globalTransform, light);
        }
    }
}