Question

I am trying to construct an Asteroid type remake using classes, i have a class for making the ship here:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;

namespace AsteroidsTest {
    class Character {
        KeyboardState inputKeyboard;
        Texture2D texture;
        Rectangle rectangle;
        Vector2 position;
        Vector2 origin;
        Vector2 speed;
        const float tangentialVelocity = 5f;
        public float rotation;

        public Character(Texture2D newTexture, int positionX, int positionY) {
            texture = newTexture;
            position = new Vector2(positionX, positionY);

    }
    public void Update(GameTime gametime, Keys KeyUp, Keys KeyRight, Keys KeyLeft) {
        inputKeyboard = Keyboard.GetState();
        rectangle = new Rectangle((int)position.X, (int)position.Y, texture.Width, texture.Height);
        position += speed;
        origin = new Vector2(rectangle.Width / 2, rectangle.Height / 2);
        if (inputKeyboard.IsKeyDown(KeyRight)) {
            rotation += 0.1f;
        } 
        else if (inputKeyboard.IsKeyDown(KeyLeft)) {
            rotation -= 0.1f;
        }
        if (inputKeyboard.IsKeyDown(KeyUp)) {
            speed.X = (float)Math.Cos(rotation) * tangentialVelocity;
            speed.Y = (float)Math.Sin(rotation) * tangentialVelocity;
        } else if (speed != Vector2.Zero) {
            speed = Vector2.Zero;
        }
    }
        public void Draw(SpriteBatch spriteBatch) {
                spriteBatch.Draw(texture, position, null, Color.White, rotation, origin, 1.0f, SpriteEffects.None, 0);
    }
}

}

But when it is drawn using my Main class below the texture on the sprite is drawn normally but when i press w to move forward, it moves me to the right. And when i rotate its as if the top of my ship is to the side, how is this possible?

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 AsteroidsTest {
    public class Asteroids : Microsoft.Xna.Framework.Game {
        GraphicsDeviceManager graphics;
        SpriteBatch spriteBatch;
        Character Ship;
        Texture2D playerTexture;


        public Asteroids() {
            graphics = new GraphicsDeviceManager(this);
            Content.RootDirectory = "Content";
        }
        protected override void Initialize() {


                base.Initialize();
        }

        protected override void LoadContent() {
            spriteBatch = new SpriteBatch(GraphicsDevice);
            playerTexture = Content.Load<Texture2D>("Actors//Ship");
            Ship = new Character(playerTexture, 16, 16); 
        }


        protected override void UnloadContent() {

        }


        protected override void Update(GameTime gameTime) {

            if (Keyboard.GetState().IsKeyDown(Keys.Escape))
                this.Exit();

            Ship.Update(gameTime, Keys.Up, Keys.Right, Keys.Left);
            base.Update(gameTime);
        }

        protected override void Draw(GameTime gameTime) {
            GraphicsDevice.Clear(Color.Black);
            spriteBatch.Begin();
            Ship.Draw(spriteBatch);
            spriteBatch.End();
            base.Draw(gameTime);
        }
    }
}

EDIT: Seems that just rotating the image 90 Degrees Clockwise fixes it, but unfortunately it defaults to that angle.

Answer 1

It is working as intended I suppose – by default (0 Rotation) implies object looking to the right and not up (with respect to your monitor / screen).