Introduced scene maps and a model loader for external models

TheRepo/DoWhateverYouWant/DoWhateverYouWant.csproj

@@ -8,6 +8,7 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="AssimpNet" Version="5.0.0-beta1" />
     <PackageReference Include="OpenTK" Version="4.8.2" />
     <PackageReference Include="StbImageSharp" Version="2.30.15" />
   </ItemGroup>

TheRepo/TheLabs/ModelLoader.cs

@@ -0,0 +1,77 @@
+namespace TheLabs;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using Assimp; // The library we just installed
+using OpenTK.Mathematics;
+
+public static class ModelLoader
+{
+    public static Mesh LoadMesh(string path)
+    {
+        var importer = new AssimpContext();
+        
+        var scene = importer.ImportFile(path, PostProcessSteps.Triangulate | PostProcessSteps.JoinIdenticalVertices);
+
+        if (scene == null || scene.SceneFlags.HasFlag(SceneFlags.Incomplete) || scene.RootNode == null)
+        {
+            throw new Exception("Error loading model: " + path);
+        }
+        
+        // --- NEW LOGIC: Combine all meshes into one ---
+        List<float> allVertices = new List<float>();
+        List<uint> allIndices = new List<uint>();
+        
+        // We need to track how many vertices we've added so far
+        // so the indices point to the correct new location
+        uint indexOffset = 0;
+
+        // Loop through EVERY mesh found in the file (Legs, Torso, Head, etc.)
+        foreach (var mesh in scene.Meshes)
+        {
+            // 1. Process Vertices for this specific part
+            for (int i = 0; i < mesh.VertexCount; i++)
+            {
+                // Position (x, y, z)
+                var pos = mesh.Vertices[i];
+                allVertices.Add(pos.X);
+                allVertices.Add(pos.Y);
+                allVertices.Add(pos.Z);
+
+                // Texture Coordinates (u, v)
+                if (mesh.HasTextureCoords(0))
+                {
+                    var uv = mesh.TextureCoordinateChannels[0][i];
+                    allVertices.Add(uv.X);
+                    allVertices.Add(uv.Y);
+                }
+                else
+                {
+                    allVertices.Add(0.0f);
+                    allVertices.Add(0.0f);
+                }
+            }
+
+            // 2. Process Indices for this specific part
+            for (int i = 0; i < mesh.FaceCount; i++)
+            {
+                var face = mesh.Faces[i];
+                for (int j = 0; j < face.IndexCount; j++)
+                {
+                    // CRITICAL: We add the offset to the index!
+                    // If the leg had 100 vertices, the first vertex of the torso
+                    // needs to be index 100, not 0.
+                    allIndices.Add((uint)(face.Indices[j] + indexOffset));
+                }
+            }
+
+            // Increase the offset by the number of vertices we just added
+            indexOffset += (uint)mesh.VertexCount;
+        }
+
+        // Return one giant Mesh containing the whole character
+        return new Mesh(allVertices.ToArray(), allIndices.ToArray(), Mesh.VertexLayout.PosTex);
+    }
+
+    
+}

TheRepo/TheLabs/MyExampleWindow.cs

@@ -1,4 +1,5 @@
-using OpenTK.Graphics.OpenGL4;
+using Assimp;
+using OpenTK.Graphics.OpenGL4;
 using OpenTK.Windowing.Common;
 using OpenTK.Windowing.GraphicsLibraryFramework;
 using OpenTK.Windowing.Desktop;
@@ -16,22 +17,20 @@ namespace TheLabs
         // Negative Y coordinates move to the bottom, positive Y move to the top.
         // OpenGL only supports rendering in 3D, so to create a flat triangle, the Z coordinate will be kept as 0.
         
+        private SceneNode _rootNode;
+        private SceneNode _characterNode;
+        private SceneNode _buildingNode;
         private Shader _shader;
         private Camera _camera;
         // - Resources that only need to be created once
-        private Mesh _cubeMesh;
+        private Mesh _exampleObject;
-        private Mesh _circleMesh;
+        private Mesh _buildingObject;
-        private Mesh _cylinderMesh;
+        private Texture _texture;
-        private Texture _cubeTexture;
+        private RenderObject _render;
-        private Texture _cubeTexture2;
+        private RenderObject _buildingRender;
-        private float _rotation;
+        float _rotation = 0.0f;
         
         // -- Scene Objects
-        private RenderObject _cubeObject;
-        private RenderObject _cubeObject2;
-        private RenderObject _circleObject;
-        private RenderObject _cylinderObject;
-        private Bus _bus;
         
         private Vector3 _cameraPosition = new Vector3(0.0f, 0.0f, -3.0f);
         private Vector3 _cameraFront = new Vector3(0.0f, 0.0f, -1.0f);
@@ -62,20 +61,31 @@ namespace TheLabs
             //GL.Disable(EnableCap.CullFace);
             
             //GL.PolygonMode(MaterialFace.FrontAndBack, PolygonMode.Line);
-            // Set The background color to a nice blue.
             GL.ClearColor(0.2f, 0.3f, 0.3f, 1.0f); 
             GL.Enable(EnableCap.DepthTest);
             _camera = new Camera(_cameraPosition, _cameraFront, _cameraUp);
+            _shader = new Shader("Shaders/shader.vert", "Shaders/shader.frag");
+            _texture = new Texture("Textures/texture-a.png");
+            
+            _rootNode = new SceneNode();
+            _exampleObject = ModelLoader.LoadMesh("Objects/cat.obj");
+            _buildingObject = ModelLoader.LoadMesh("Objects/building1.obj");
+            _render = new RenderObject(_exampleObject, _shader, _texture);
+            _buildingRender = new RenderObject(_buildingObject, _shader, _texture);
+            
+            _characterNode = new SceneNode(_render);
+            _characterNode.Position = new Vector3(0.0f, -1.0f, 0.0f);
+            _rootNode.AddChild(_characterNode);
+            
+            _buildingNode = new SceneNode(_buildingRender);
+            _buildingNode.Position = new Vector3(2.0f, -1.0f, 0.0f);
+            _rootNode.AddChild(_buildingNode);
+            
+            
+            
             
             CursorState = CursorState.Grabbed;
 
-            _shader = new Shader("Shaders/shader.vert", "Shaders/shader.frag");
-            _cubeTexture = new Texture("Textures/placeholder.png");
-            _cubeTexture2 = new Texture("Textures/placeholder.png");
-            
-            _bus = new Bus(_cubeTexture, _shader);
-            
-            
 
 
         }
@@ -105,9 +115,8 @@ namespace TheLabs
                 0.1f,
                 100.0f
             );
-            
             // --- Draw Scene Objects ---
-            _bus.DrawBus(view, projection);
+            _rootNode.Draw(view, projection, Matrix4.Identity);
             
             SwapBuffers();
         }

TheRepo/TheLabs/RenderObject.cs

@@ -28,7 +28,7 @@ public class RenderObject
         Shader.Use();
         Shader.SetInt("uTexture", 0);
         // 2. Bind Texture
-        Texture.Use(); // Assumes you have a Texture class
+        Texture.Use();
         // 3. Calculate Model Matrix
         Matrix4 model = Matrix4.CreateScale(Scale) * Matrix4.CreateFromQuaternion(Rotation) * Matrix4.CreateTranslation(Position);        
         int modelLoc = GL.GetUniformLocation(Shader.Handle, "model");

TheRepo/TheLabs/SceneNode.cs

@@ -0,0 +1,45 @@
+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)
+    {
+        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);
+        }
+
+        foreach (var child in Children)
+        {
+            child.Draw(view, projection, globalTransform);
+        }
+    }
+}

TheRepo/TheLabs/Shapes/Bus.cs

@@ -5,85 +5,70 @@ namespace TheLabs.Shapes;
 
 public class Bus
 {
+    public SceneNode MainNode;
+    
     private Mesh _wheelMesh;
-    private RenderObject _wheelObject;
+    private Mesh _bodyMesh;
+    private Mesh _roofMesh;
     
-    private Texture _wheelTexture;
-    private Shader _wheelShader;
-    private Texture _bodyTexture;
 
-    public Bus(Texture texture, Shader shader)
+    public Bus(Texture wheelTexture,Texture bodyTexture, Shader shader)
     {
-        _wheelTexture = new Texture("Textures/rubber.jpg");
-        _wheelShader = shader;
-        
-        _bodyTexture = new Texture("Textures/rust.png");
-    }
-    
-    public void DrawWheel(Matrix4 view, Matrix4 projection, Vector3 position)
-    {
-        Matrix4 localTransform = Matrix4.Identity;
-        //Matrix4 comboTransform = localTransform * _wheelObject.Transform;
-
         _wheelMesh = ShapeFactory.CreateTexturedCylinder();
-        _wheelObject = new RenderObject(_wheelMesh, _wheelShader, _wheelTexture);
+        _bodyMesh = ShapeFactory.CreateTexturedCube();
+        _roofMesh = ShapeFactory.CreateTexturedCylinder();
         
-        // Front Left Wheel
+        MainNode = new SceneNode();
-        _wheelObject.Position = new Vector3(position);
-        _wheelObject.Scale = new Vector3(0.3f, 0.1f, 0.2f);
-        _wheelObject.Rotation = Quaternion.FromAxisAngle(Vector3.UnitX, MathHelper.DegreesToRadians(90.0f));
         
-        _wheelObject.Draw(view, projection);
+        // Building the body
+        var bodyObj = new RenderObject(_bodyMesh, shader, bodyTexture);
+        var bodyNode = new SceneNode(bodyObj);
+        bodyNode.Scale = new Vector3(1.5f, 0.5f, 0.5f);
+        bodyNode.Scale = new Vector3(0.0f, 0.0f, 0.0f);
+        MainNode.AddChild(bodyNode);
         
-    }
+        // Building the body
+        var roofObj = new RenderObject(_roofMesh, shader, bodyTexture);
+        var roofNode = new SceneNode(roofObj);
+        roofNode.Position = new Vector3(0.0f, 0.25f, 0.0f);
+        roofNode.Scale = new Vector3(0.5f, 1.5f, .25f);
+        roofNode.Rotation = Quaternion.FromAxisAngle(Vector3.UnitY, MathHelper.DegreesToRadians(90.0f));
+        roofNode.Rotation *= Quaternion.FromAxisAngle(Vector3.UnitX, MathHelper.DegreesToRadians(90.0f));
+        MainNode.AddChild(roofNode);
         
-    public void drawBody(Matrix4 view, Matrix4 projection)
+        // Building the wheels
-    {
-        Mesh bodyMesh = ShapeFactory.CreateTexturedCube();
-        RenderObject bodyObject = new RenderObject(bodyMesh, _wheelShader, _bodyTexture);
         
-        bodyObject.Position = new Vector3(0.0f, 0.0f, 0.0f);
-        bodyObject.Scale = new Vector3(1.5f, 0.5f, 0.5f);
-        
-        bodyObject.Draw(view, projection);
-    }
-
-    private void drawRoof(Matrix4 view, Matrix4 projection)
-    {
-        Mesh roofMesh = ShapeFactory.CreateTexturedCylinder();
-        RenderObject roofObject = new RenderObject(roofMesh, _wheelShader, _bodyTexture);
-        
-        roofObject.Position = new Vector3(0.0f, 0.25f, 0.0f);
-        roofObject.Scale = new Vector3(0.5f, 1.5f, .25f);
-        
-        roofObject.Rotation = Quaternion.FromAxisAngle(Vector3.UnitY, MathHelper.DegreesToRadians(90.0f));
-        roofObject.Rotation *= Quaternion.FromAxisAngle(Vector3.UnitX, MathHelper.DegreesToRadians(90.0f));
-        
-
-        
-        roofObject.Draw(view, projection);
-    }
-
-    public void DrawBus(Matrix4 view, Matrix4 projection)
-    {
-        // Drawing 4 wheels
         float xOffset = 0.4f; // Reduced to bring wheels closer to the body
         float zOffset = 0.28f; // Reduced to bring front and back wheels closer
         float yOffset = -0.3f; // Adjusted to ensure wheels touch the body
 
-        // Drawing 4 wheels
+        Vector3[] wheelPositions =
-        for (int i = 0; i < 4; i++)
         {
-            float xPosition = (i % 2 == 0) ? -xOffset : xOffset; // Left or Right
+            new Vector3(-xOffset, yOffset, zOffset), // Front Left
-            float zPosition = (i < 2) ? zOffset : -zOffset;      // Front or Back
+            new Vector3(xOffset, yOffset, zOffset), // Front Right
+            new Vector3(-xOffset, yOffset, -zOffset), // Back Left
+            new Vector3(xOffset, yOffset, -zOffset) // Back Right
+        };
         
-            DrawWheel(view, projection, new Vector3(xPosition, yOffset, zPosition));
+        foreach (var pos in wheelPositions)
+        {
+            var wheelObj = new RenderObject(_wheelMesh, shader, wheelTexture);
+            var wheelNode = new SceneNode(wheelObj);
+            
+            wheelNode.Position = pos; // Relative to the MainNode!
+            wheelNode.Scale = new Vector3(0.3f, 0.1f, 0.2f);
+            // Rotate cylinder to act like a wheel
+            wheelNode.Rotation = Quaternion.FromAxisAngle(Vector3.UnitX, MathHelper.DegreesToRadians(90.0f));
+            
+            MainNode.AddChild(wheelNode);
         }
 
-        // Drawing the body
+    }
-        drawBody(view, projection);
+    
-        // Drawing the roof
+    
-        drawRoof(view, projection);
+    public void Draw(Matrix4 view, Matrix4 projection)
+    {
+        MainNode.Draw(view, projection, Matrix4.Identity);
     }
     
 

TheRepo/TheLabs/Texture.cs

@@ -18,7 +18,6 @@ public class Texture : IDisposable
         GL.BindTexture(TextureTarget.Texture2D, Handle);
 
         // --- Set texture parameters ---
-        // Repeat the texture if UVs go outside [0, 1]
         GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (int)TextureWrapMode.Repeat);
         GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int)TextureWrapMode.Repeat);
         

TheRepo/TheLabs/TheLabs.csproj

@@ -8,6 +8,7 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="AssimpNet" Version="5.0.0-beta1" />
     <PackageReference Include="OpenTK" Version="4.8.2" />
     <PackageReference Include="StbImageSharp" Version="2.30.15" />
   </ItemGroup>

TheRepo/VectorAndMatrixTests/VectorAndMatrixTests.csproj

@@ -10,6 +10,7 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="AssimpNet" Version="5.0.0-beta1" />
     <PackageReference Include="coverlet.collector" Version="6.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
     <PackageReference Include="MSTest.TestAdapter" Version="3.1.1" />