Creating Meshes

Checked with version: 5

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Difficulty: Advanced

Creating Meshes.

Creating Meshes

Advanced Scripting

MapGenerator

Code snippet

using UnityEngine;
using System.Collections;
using System;

public class MapGenerator : MonoBehaviour {

    public int width;
    public int height;

    public string seed;
    public bool useRandomSeed;

    [Range(0,100)]
    public int randomFillPercent;

    int[,] map;

    void Start() {
        GenerateMap();
    }

    void Update() {
        if (Input.GetMouseButtonDown(0)) {
            GenerateMap();
        }
    }

    void GenerateMap() {
        map = new int[width,height];
        RandomFillMap();

        for (int i = 0; i < 5; i ++) {
            SmoothMap();
        }

        MeshGenerator meshGen = GetComponent<MeshGenerator>();
        meshGen.GenerateMesh(map, 1);
    }


    void RandomFillMap() {
        if (useRandomSeed) {
            seed = Time.time.ToString();
        }

        System.Random pseudoRandom = new System.Random(seed.GetHashCode());

        for (int x = 0; x < width; x ++) {
            for (int y = 0; y < height; y ++) {
                if (x == 0 || x == width-1 || y == 0 || y == height -1) {
                    map[x,y] = 1;
                }
                else {
                    map[x,y] = (pseudoRandom.Next(0,100) < randomFillPercent)? 1: 0;
                }
            }
        }
    }

    void SmoothMap() {
        for (int x = 0; x < width; x ++) {
            for (int y = 0; y < height; y ++) {
                int neighbourWallTiles = GetSurroundingWallCount(x,y);

                if (neighbourWallTiles > 4)
                    map[x,y] = 1;
                else if (neighbourWallTiles < 4)
                    map[x,y] = 0;

            }
        }
    }

    int GetSurroundingWallCount(int gridX, int gridY) {
        int wallCount = 0;
        for (int neighbourX = gridX - 1; neighbourX <= gridX + 1; neighbourX ++) {
            for (int neighbourY = gridY - 1; neighbourY <= gridY + 1; neighbourY ++) {
                if (neighbourX >= 0 && neighbourX < width && neighbourY >= 0 && neighbourY < height) {
                    if (neighbourX != gridX || neighbourY != gridY) {
                        wallCount += map[neighbourX,neighbourY];
                    }
                }
                else {
                    wallCount ++;
                }
            }
        }

        return wallCount;
    }


    void OnDrawGizmos() {
        /*
        if (map != null) {
            for (int x = 0; x < width; x ++) {
                for (int y = 0; y < height; y ++) {
                    Gizmos.color = (map[x,y] == 1)?Color.black:Color.white;
                    Vector3 pos = new Vector3(-width/2 + x + .5f,0, -height/2 + y+.5f);
                    Gizmos.DrawCube(pos,Vector3.one);
                }
            }
        }
        */
    }
}

MeshGenerator

Code snippet

using UnityEngine;
using System.Collections;
using System.Collections.Generic;

public class MeshGenerator : MonoBehaviour {

    public SquareGrid squareGrid;
    List<Vector3> vertices;
    List<int> triangles;

    public void GenerateMesh(int[,] map, float squareSize) {
        squareGrid = new SquareGrid(map, squareSize);

        vertices = new List<Vector3>();
        triangles = new List<int>();

        for (int x = 0; x < squareGrid.squares.GetLength(0); x ++) {
            for (int y = 0; y < squareGrid.squares.GetLength(1); y ++) {
                TriangulateSquare(squareGrid.squares[x,y]);
            }
        }

        Mesh mesh = new Mesh();
        GetComponent<MeshFilter>().mesh = mesh;

        mesh.vertices = vertices.ToArray();
        mesh.triangles = triangles.ToArray();
        mesh.RecalculateNormals();
    }

    void TriangulateSquare(Square square) {
        switch (square.configuration) {
        case 0:
            break;

        // 1 points:
        case 1:
            MeshFromPoints(square.centreBottom, square.bottomLeft, square.centreLeft);
            break;
        case 2:
            MeshFromPoints(square.centreRight, square.bottomRight, square.centreBottom);
            break;
        case 4:
            MeshFromPoints(square.centreTop, square.topRight, square.centreRight);
            break;
        case 8:
            MeshFromPoints(square.topLeft, square.centreTop, square.centreLeft);
            break;

        // 2 points:
        case 3:
            MeshFromPoints(square.centreRight, square.bottomRight, square.bottomLeft, square.centreLeft);
            break;
        case 6:
            MeshFromPoints(square.centreTop, square.topRight, square.bottomRight, square.centreBottom);
            break;
        case 9:
            MeshFromPoints(square.topLeft, square.centreTop, square.centreBottom, square.bottomLeft);
            break;
        case 12:
            MeshFromPoints(square.topLeft, square.topRight, square.centreRight, square.centreLeft);
            break;
        case 5:
            MeshFromPoints(square.centreTop, square.topRight, square.centreRight, square.centreBottom, square.bottomLeft, square.centreLeft);
            break;
        case 10:
            MeshFromPoints(square.topLeft, square.centreTop, square.centreRight, square.bottomRight, square.centreBottom, square.centreLeft);
            break;

        // 3 point:
        case 7:
            MeshFromPoints(square.centreTop, square.topRight, square.bottomRight, square.bottomLeft, square.centreLeft);
            break;
        case 11:
            MeshFromPoints(square.topLeft, square.centreTop, square.centreRight, square.bottomRight, square.bottomLeft);
            break;
        case 13:
            MeshFromPoints(square.topLeft, square.topRight, square.centreRight, square.centreBottom, square.bottomLeft);
            break;
        case 14:
            MeshFromPoints(square.topLeft, square.topRight, square.bottomRight, square.centreBottom, square.centreLeft);
            break;

        // 4 point:
        case 15:
            MeshFromPoints(square.topLeft, square.topRight, square.bottomRight, square.bottomLeft);
            break;
        }
    }

    void MeshFromPoints(params Node[] points) {
        AssignVertices(points);

        if (points.Length >= 3)
            CreateTriangle(points[0], points[1], points[2]);
        if (points.Length >= 4)
            CreateTriangle(points[0], points[2], points[3]);
        if (points.Length >= 5) 
            CreateTriangle(points[0], points[3], points[4]);
        if (points.Length >= 6)
            CreateTriangle(points[0], points[4], points[5]);
    }

    void AssignVertices(Node[] points) {
        for (int i = 0; i < points.Length; i ++) {
            if (points[i].vertexIndex == -1) {
                points[i].vertexIndex = vertices.Count;
                vertices.Add(points[i].position);
            }
        }
    }

    void CreateTriangle(Node a, Node b, Node c) {
        triangles.Add(a.vertexIndex);
        triangles.Add(b.vertexIndex);
        triangles.Add(c.vertexIndex);
    }

    void OnDrawGizmos() {
        /*
        if (squareGrid != null) {
            for (int x = 0; x < squareGrid.squares.GetLength(0); x ++) {
                for (int y = 0; y < squareGrid.squares.GetLength(1); y ++) {
                    Gizmos.color = (squareGrid.squares[x,y].topLeft.active)?Color.black:Color.white;
                    Gizmos.DrawCube(squareGrid.squares[x,y].topLeft.position, Vector3.one * .4f);
                    Gizmos.color = (squareGrid.squares[x,y].topRight.active)?Color.black:Color.white;
                    Gizmos.DrawCube(squareGrid.squares[x,y].topRight.position, Vector3.one * .4f);
                    Gizmos.color = (squareGrid.squares[x,y].bottomRight.active)?Color.black:Color.white;
                    Gizmos.DrawCube(squareGrid.squares[x,y].bottomRight.position, Vector3.one * .4f);
                    Gizmos.color = (squareGrid.squares[x,y].bottomLeft.active)?Color.black:Color.white;
                    Gizmos.DrawCube(squareGrid.squares[x,y].bottomLeft.position, Vector3.one * .4f);
                    Gizmos.color = Color.grey;
                    Gizmos.DrawCube(squareGrid.squares[x,y].centreTop.position, Vector3.one * .15f);
                    Gizmos.DrawCube(squareGrid.squares[x,y].centreRight.position, Vector3.one * .15f);
                    Gizmos.DrawCube(squareGrid.squares[x,y].centreBottom.position, Vector3.one * .15f);
                    Gizmos.DrawCube(squareGrid.squares[x,y].centreLeft.position, Vector3.one * .15f);
                }
            }
        }
        */
    }
    
    public class SquareGrid {
        public Square[,] squares;

        public SquareGrid(int[,] map, float squareSize) {
            int nodeCountX = map.GetLength(0);
            int nodeCountY = map.GetLength(1);
            float mapWidth = nodeCountX * squareSize;
            float mapHeight = nodeCountY * squareSize;

            ControlNode[,] controlNodes = new ControlNode[nodeCountX,nodeCountY];

            for (int x = 0; x < nodeCountX; x ++) {
                for (int y = 0; y < nodeCountY; y ++) {
                    Vector3 pos = new Vector3(-mapWidth/2 + x * squareSize + squareSize/2, 0, -mapHeight/2 + y * squareSize + squareSize/2);
                    controlNodes[x,y] = new ControlNode(pos,map[x,y] == 1, squareSize);
                }
            }

            squares = new Square[nodeCountX -1,nodeCountY -1];
            for (int x = 0; x < nodeCountX-1; x ++) {
                for (int y = 0; y < nodeCountY-1; y ++) {
                    squares[x,y] = new Square(controlNodes[x,y+1], controlNodes[x+1,y+1], controlNodes[x+1,y], controlNodes[x,y]);
                }
            }

        }
    }
    
    public class Square {

        public ControlNode topLeft, topRight, bottomRight, bottomLeft;
        public Node centreTop, centreRight, centreBottom, centreLeft;
        public int configuration;

        public Square (ControlNode _topLeft, ControlNode _topRight, ControlNode _bottomRight, ControlNode _bottomLeft) {
            topLeft = _topLeft;
            topRight = _topRight;
            bottomRight = _bottomRight;
            bottomLeft = _bottomLeft;

            centreTop = topLeft.right;
            centreRight = bottomRight.above;
            centreBottom = bottomLeft.right;
            centreLeft = bottomLeft.above;

            if (topLeft.active)
                configuration += 8;
            if (topRight.active)
                configuration += 4;
            if (bottomRight.active)
                configuration += 2;
            if (bottomLeft.active)
                configuration += 1;
        }
    }

    public class Node {
        public Vector3 position;
        public int vertexIndex = -1;

        public Node(Vector3 _pos) {
            position = _pos;
        }
    }

    public class ControlNode : Node {

        public bool active;
        public Node above, right;

        public ControlNode(Vector3 _pos, bool _active, float squareSize) : base(_pos) {
            active = _active;
            above = new Node(position + Vector3.forward * squareSize/2f);
            right = new Node(position + Vector3.right * squareSize/2f);
        }
    }
}

Sebastian Lague

Community author

Sebastian Lague started out ambitiously making games with AppleScript when he was twelve. He had considerably greater success two years later when he discovered the Unity engine and has been engrossed in game development ever since. He loves participating in game jams with friends and has a growing passion for teaching game development at all levels.

Scripting

  1. Scripts as Behaviour Components
  2. Variables and Functions
  3. Conventions and Syntax
  4. C# vs JS syntax
  5. IF Statements
  6. Loops
  7. Scope and Access Modifiers
  8. Awake and Start
  9. Update and FixedUpdate
  10. Vector Maths
  11. Enabling and Disabling Components
  12. Activating GameObjects
  13. Translate and Rotate
  14. Look At
  15. Linear Interpolation
  16. Destroy
  17. GetButton and GetKey
  18. GetAxis
  19. OnMouseDown
  20. GetComponent
  21. Delta Time
  22. Data Types
  23. Classes
  24. Instantiate
  25. Arrays
  26. Invoke
  27. Enumerations
  28. Switch Statements
  1. Properties
  2. Ternary Operator
  3. Statics
  4. Method Overloading
  5. Generics
  6. Inheritance
  7. Polymorphism
  8. Member Hiding
  9. Overriding
  10. Interfaces
  11. Extension Methods
  12. Namespaces
  13. Lists and Dictionaries
  14. Coroutines
  15. Quaternions
  16. Delegates
  17. Attributes
  18. Events
  1. Building a Custom Inspector
  2. The DrawDefaultInspector Function
  3. Adding Buttons to a Custom Inspector
  1. MonoDevelop's Debugger
  2. Good Coding Practices in Unity
  3. Unity Editor Extensions – Menu Items
  4. Creating Meshes
  1. AssetBundles and the AssetBundle Manager
  2. Mastering Unity Project Folder Structure - Version Control Systems
  1. Installing Tools for Unity Development
  2. Building your first Unity Game with Visual Studio
  3. Editing Unity games in Visual Studio
  4. Debugging Unity games in Visual Studio
  5. Graphics debugging Unity games in Visual Studio
  6. Taking Unity games to Universal Windows Platform
  7. Testing Unity games on Android in Visual Studio
  1. Scripting Primer and Q&A
  2. Scripting Primer and Q&A - Continued
  3. Scripting Primer and Q&A - Continued (Again)
  4. Persistence - Saving and Loading Data
  5. Object Pooling
  6. Introduction to Scriptable Objects
  7. How to communicate between Scripts and GameObjects
  8. Coding in Unity for the Absolute Beginner
  9. Sound Effects & Scripting
  10. Editor Scripting Intro
  11. Writing Plugins
  12. Property Drawers & Custom Inspectors
  13. Events: Creating a simple messaging system
  14. Ability System with Scriptable Objects
  15. Character Select System with Scriptable Objects
  1. Intro and Setup
  2. Data Classes
  3. Menu Screen
  4. Game UI
  5. Answer Button
  6. Displaying Questions
  7. Click To Answer
  8. Ending The Game and Q&A
  1. Intro To Part Two
  2. High Score with PlayerPrefs
  3. Serialization and Game Data
  4. Loading Game Data via JSON
  5. Loading and Saving via Editor Script
  6. Game Data Editor GUI
  7. Question and Answer
  1. Overview and Goals
  2. Localization Data
  3. Dictionary, JSON and Streaming Assets
  4. Localization Manager
  5. Startup Manager
  6. Localized Text Component
  7. Localized Text Editor Script
  8. Localization Q&A
  1. Introduction and Session Goals
  2. Particle Launcher
  3. Particle Collisions
  4. ParticleLauncher Script
  5. Particle Collisions and Scripting
  6. Random Particle Colors
  7. Drawing Decals with Particles
  8. Collecting Particle Information For Display
  9. Displaying Particles Via Script
  10. Droplet Decals
  11. Questions and Answers