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Revision as of 12:05, 27 October 2017
Contents
Original Tutorial
the original tutorial can be found on the link below:
Create a new project
Using the MonoGame templates, create a MonoGame Windows Project.
Resources Required
All of the resources for this tutorial can be downloaded here. Extract these files into the Content folder for your project.
In Visual Studio, double click the Content.mgcb file in the solution explorer panel. This will run the content pipeline tool. In the content pipeline tool, click the add existing item icon. Now browse for the Content folder of your project, and select all of the png & wav files downloaded above.
Now build the pipeline, you should see zero errors and each of the 9 items should be successful.
Getting Started
Game1.cs Using References
At the very start of the Game1.cs file, you will find some using declarations. make sure the following are included:
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Content;
Game1.cs Declarations
Find the line of code which states 'SpriteBatch spriteBatch;', now press enter to go onto the next line.
This is where you can declare any variables within your game. We are going to declare some Texture2D for the sprites/graphics within this game and also some sound effects. The Vector2 variables are to control the position and movement of the paddle and ball. Add the following declarations:
public Texture2D imgBrick;
public Texture2D imgPaddle;
public Texture2D imgBall;
public Texture2D imgPixel;
public SoundEffect startSound;
public SoundEffect brickSound;
public SoundEffect paddleBounceSound;
public SoundEffect wallBounceSound;
public SoundEffect missSound;
public Vector2 paddlePosition;
public Vector2 ballMovement;
public Vector2 ballPosition;
public bool ballInMotion = false;
public int speed = 8;
Game1.cs Constructor
To set the size of your screen, enter the following commands in the constructor method. A constructor method is uses the name of the class, so look for 'public Game1()' This is run once when your game is created:
graphics.PreferredBackBufferHeight = 600;
graphics.PreferredBackBufferWidth = 400;
Game1.cs LoadContent
Now find the LoadContent method of Game1.cs. This is the method to load all of your game assets into your game. We will use this to load your built resources and to assign them to the variables we have declared above.
So add the following code to the LoadContent method:
//load images
imgBall = Content.Load<Texture2D>("Ball");
imgPixel = Content.Load<Texture2D>("Pixel");
imgPaddle = Content.Load<Texture2D>("Paddle");
imgBrick = Content.Load<Texture2D>("Brick");
//load sounds
startSound = Content.Load<SoundEffect>("StartSound");
brickSound = Content.Load<SoundEffect>("BrickSound");
paddleBounceSound = Content.Load<SoundEffect>("PaddleBounceSound");
wallBounceSound = Content.Load<SoundEffect>("WallBounceSound");
missSound = Content.Load<SoundEffect>("MissSound");
paddlePosition = new Vector2((graphics.PreferredBackBufferWidth / 2) - imgPaddle.Width, 550);
Game1.cs Update
The update method is essentially the game loop and is continuously run for your game, it will be run before the draw method is called.
This method will be used to read the user input and move any of the sprite characters. So to move the paddle we can add the following code:
if (Keyboard.GetState().IsKeyDown(Keys.Z)
{
if (paddlePostion.X < 0)
paddlePosition.X = 0;
else
paddlePosition.X -= 2;
}
if (Keyboard.GetState().IsKeyDown(Keys.X)
{
if (paddlePostion.X > (graphics.PreferredBackBufferWidth - imgPaddle.Width))
paddlePosition.X = graphics.PreferredBackBufferWidth - imgPaddle.Width;
else
paddlePosition.X += 2;
}
Game1.cs Draw Method
This will always be run after the update method. So add the following code into the Draw method:
spriteBatch.Begin();
spriteBatch.Draw(imgPaddle, paddlePostion);
spriteBatch.End();
If you test the game you should be able to control the paddle on the screen, test if it can go off the screen.
The Ball
Set the starting position
The ball should normally start on the paddle so to calculate the starting position we can enter the following in the Game1.cs Update method:
if(!ballInMotion)
ballPosition = new Vector2(paddlePosition.X + (imgPaddle.Width / 2) - (imgBall.Width / 2),
paddlePosition.Y - imgBall.Height);
else
ballPosition += ballMovement;
If ballInMotion is false this will position the ball on top of the paddle in the middle. If ball is in motion we can keep adding the ballMovement vector to the ballPosition.
Serving the ball
To serve the ball, we are going to use a key press. This will set ballInMotion to be true, and we will also set the ballMovement vector. So add the following after the code for your starting position:
if(Keyboard.GetState().IsKeyDown(Keys.Space))
{
ballInMotion = true;
ballMovement = new Vector2(-1, -(speed));
}
in the vector -1 represents the x axis, so this will go to the left by 1. Speed is set to 8, so this will move up the screen by 8. If we keep applying this vector the ball will travel in a straight line.
Bouncing the ball around the screen
Using a vector to control the movement of the ball will allow you to easily bounce the ball by manipulating the vector.
If the ball is currently on a vector of (4 , -8) it will be travelling up the screen and to the right. If this causes it to bounce off the right hand side of the screen we can simply minus the x value of the vector to make (-4 , -8).
The same is true for a bounce from the left of the screen, a original vector of (-4 , -8) will translate into a bounce of (4 , -8).
For the top or bottom of the screen you need to minus just the Y value of your vector. So a bounce off the top using a vector of (4 , -8) will create a bounce vector of (4 , 8).
A bounce off the bottom from a vector (4 , 8) will create a bounce of (4 , -8), and a vector of (-4 , 8) will create a bounce vector of (-4 , -8).
We can do this in code by creating this method, paste it within the Game1 class but not in any other method:
public Vector2 Bounce (Vector2 current, bool Vertical, SoundEffect sound)
{
if (Vertical)
current = new Vector2(current.X , -(current.Y));
else
current = new Vector2(-(current.X) , current.Y);
sound.Play();
return current;
}