衝突検出をテストするための簡単なゲームを作成しようとしていますが、正しく動作しません。正常にビルドされますが、実行時に「NullReferenceException: オブジェクト参照がオブジェクトのインスタンスに設定されていません」というエラーが発生します。
SpriteManager.cs:
using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.GamerServices;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Media;
namespace Project_3
{
public class SpriteManager : Microsoft.Xna.Framework.DrawableGameComponent
{
private Game1 _Game1;
//SpriteBatch for drawing
SpriteBatch spriteBatch;
//A sprite for the player and a list of automated sprites
UserControlledSprite player;
List<Sprite> spriteList = new List<Sprite>();
public SpriteManager(Game1 game)
: base(game)
{
// TODO: Construct any child components here
_Game1 = game;
}
public override void Initialize()
{
// TODO: Add your initialization code here
base.Initialize();
}
protected override void LoadContent()
{
spriteBatch = new SpriteBatch(Game.GraphicsDevice);
//Load the player sprite
player = new UserControlledSprite(
Game.Content.Load<Texture2D>("Images/bill"),
Vector2.Zero, 10, new Vector2(6, 6));
//Load several different automated sprites into the list
spriteList.Add(new AutomatedSprite(
Game.Content.Load<Texture2D>("Images/kit"),
new Vector2(150, 150), 10, Vector2.Zero));
spriteList.Add(new AutomatedSprite(
Game.Content.Load<Texture2D>("Images/kit"),
new Vector2(300, 150), 10, Vector2.Zero));
spriteList.Add(new AutomatedSprite(
Game.Content.Load<Texture2D>("Images/beast"),
new Vector2(150, 300), 10, Vector2.Zero));
spriteList.Add(new AutomatedSprite(
Game.Content.Load<Texture2D>("Images/beast"),
new Vector2(600, 400), 10, Vector2.Zero));
base.LoadContent();
}
public override void Update(GameTime gameTime)
{
// Update player
player.Update(gameTime, Game.Window.ClientBounds);
// Update all sprites
foreach (Sprite s in spriteList)
{
s.Update(gameTime, Game.Window.ClientBounds);
}
base.Update(gameTime);
}
public override void Draw(GameTime gameTime)
{
spriteBatch.Begin(SpriteSortMode.FrontToBack, BlendState.AlphaBlend);
// Draw the player
player.Draw(gameTime, spriteBatch);
// Draw all sprites
foreach (Sprite s in spriteList)
s.Draw(gameTime, spriteBatch);
spriteBatch.End();
base.Draw(gameTime);
}
}
}
例外をスローする行はplayer.Update(gameTime, Game.Window.ClientBounds);fromSpriteManagerです。完全な例外メッセージは、「プロジェクト 3.exe で 'System.NullReferenceException' 型の未処理の例外が発生しました。追加情報: オブジェクト参照がオブジェクトのインスタンスに設定されていません。」
UserControlledSprite.cs:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
namespace Project_3
{
class UserControlledSprite : Sprite
{
// Movement stuff
MouseState prevMouseState;
// Get direction of sprite based on player input and speed
public override Vector2 direction
{
get
{
Vector2 inputDirection = Vector2.Zero;
// If player pressed arrow keys, move the sprite
if (Keyboard.GetState().IsKeyDown(Keys.Left))
inputDirection.X -= 1;
if (Keyboard.GetState().IsKeyDown(Keys.Right))
inputDirection.X += 1;
if (Keyboard.GetState().IsKeyDown(Keys.Up))
inputDirection.Y -= 1;
if (Keyboard.GetState().IsKeyDown(Keys.Down))
inputDirection.Y += 1;
// If player pressed the gamepad thumbstick, move the sprite
GamePadState gamepadState = GamePad.GetState(PlayerIndex.One);
if (gamepadState.ThumbSticks.Left.X != 0)
inputDirection.X += gamepadState.ThumbSticks.Left.X;
if (gamepadState.ThumbSticks.Left.Y != 0)
inputDirection.Y -= gamepadState.ThumbSticks.Left.Y;
return inputDirection * speed;
}
}
public UserControlledSprite(Texture2D textureImage, Vector2 position, int collisionOffset, Vector2 speed)
{
}
public override void Update(GameTime gameTime, Rectangle clientBounds)
{
// Move the sprite based on direction
position += direction;
// If player moved the mouse, move the sprite
MouseState currMouseState = Mouse.GetState();
if (currMouseState.X != prevMouseState.X ||
currMouseState.Y != prevMouseState.Y)
{
position = new Vector2(currMouseState.X, currMouseState.Y);
}
prevMouseState = currMouseState;
// If sprite is off the screen, move it back within the game window
if (position.X < 0)
position.X = 0;
if (position.Y < 0)
position.Y = 0;
if (position.X > clientBounds.Width - 150)
position.X = clientBounds.Width - 150;
if (position.Y > clientBounds.Height - 150)
position.Y = clientBounds.Height - 150;
base.Update(gameTime, clientBounds);
}
}
}
なぜ機能しないのかわかりません。さまざまなことを試しましたが、xna は初めてなので、単純なものが欠けている可能性があります。
どんな助けでも大歓迎です。
編集:Sprite.csを追加するのを忘れました:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
namespace Project_3
{
abstract class Sprite
{
// Stuff needed to draw the sprite
Texture2D textureImage;
// Collision data
int collisionOffset;
// Movement data
protected Vector2 speed;
protected Vector2 position;
// Abstract definition of direction property
public abstract Vector2 direction
{
get;
}
public Sprite()
{
}
public Sprite(Texture2D textureImage, Vector2 position, int collisionOffset, Vector2 speed)
//: this(textureImage, position, collisionOffset, speed)
{
}
public virtual void Update(GameTime gameTime, Rectangle clientBounds)
{
}
public virtual void Draw(GameTime gameTime, SpriteBatch spriteBatch)
{
// Draw the sprite
if (textureImage != null)
{
spriteBatch.Draw(textureImage, position, Color.White);
}
}
// Gets the collision rect based on position, framesize and collision offset
public Rectangle collisionRect
{
get
{
return new Rectangle(
(int)position.X + collisionOffset,
(int)position.Y + collisionOffset,
150 - (collisionOffset * 2),
150 - (collisionOffset * 2));
}
}
public Game1 _Game1 { get; set; }
}
}