Creating a Texture Manager in C#

Memory management is crucial when creating a video game; you don't want to needlessly waste your resources on copies of the same thing! To tackle memory management issues, namely when it comes to large files like textures, you want to make sure that everything using the same texture is using the same instance of a texture; that is, there aren't two of the same texture loaded into memory anywhere.

To accomplish this, we can utilize the Flyweight pattern to ensure only one copy of a texture is used between many objects.

If you're curious about the design of this solution, the Flyweight deep-dive section uses a similar approach in the refactoring section.

Sprite and Texture Classes:

public interface ISprite 
{
   void Draw(int x, int y);
}

// Base class for a texture:
public class Texture
{
   string source;
   public Texture(string source)
   {
       this.source = source;
   }

}

// Enum class for faster accessing:
public enum TextureName
{
   Grass,
   Path,

}

// Implementation of a sprite:
public class Sprite: ISprite
{
   // The flyweight:
   Texture texture;

   public Sprite(Texture texture)
   {
       this.texture = texture;
   }

   public Sprite(TextureName name)
   {
       this.texture = TextureManager.GetTexture(name);
   }

   public void SetTexture(TextureName name)
   {
       this.texture = TextureManager.GetTexture(name);
   }

   public void Draw(int x, int y)
   {
       Console.WriteLine($"Drawing sprite at {x}, {y}");
   }
}

Texture Manager:

public class TextureManager
{
   static Dictionary<TextureName, Texture> cachedTextures = new Dictionary<TextureName, Texture>();

   public static void Add(TextureName name, string src)
   {
       Texture tex = new Texture(src);
       cachedTextures.Add(name, tex);
   }

   public static Texture GetTexture(TextureName name)
   {
       Texture tex = null;
       cachedTextures.TryGetValue(name, out tex);

       return tex;
   }
}

Demo:

public class Solution
{
   public static void Main(string[] args)
   {
       string grassSrc = "Grass.png";
       string pathSrc = "Path.png";

       // Add into the flyweight:
       TextureManager.Add(TextureName.Grass, grassSrc);
       TextureManager.Add(TextureName.Path, pathSrc);

       // Create two sprites using the Texture Name:
       Sprite grassSprite = new Sprite(TextureName.Grass);
       Sprite pathSprite = new Sprite(TextureName.Path);

       // Create a sprite using a Texture reference:
       Texture grass = TextureManager.GetTexture(TextureName.Grass);
       Sprite anotherSprite = new Sprite(grass);

       // Draw the sprites:

       grassSprite.Draw(0, 1);  // Drawing sprite at 0, 1
       pathSprite.Draw(0, 2); // Drawing sprite at 0, 2

       anotherSprite.Draw(0, 3); // Drawing sprite at 0, 3

       // Swap the sprite out:
       anotherSprite.SetTexture(TextureName.Path);

       anotherSprite.Draw(0, 4); // Drawing sprite at 0, 4
   }
}