Sample Game Part I - CodeProject

Download demo - 37.12 KB

Introduction

This is a sample game to demonstrate reading keyboard strokes and moving a character.

Somehow, it's a space invaders-like game, except that there's nothing to shoot!!

You can also control the speed of the character and bullet.

Initializing the Game

The game starts by initializing the bullet and character's speed:

bullet_speed = 4;
character_speed = 2;

Notice that I've used the same values in the numlists.

Moving the Character

In order to move the character, we start by reading the currently pressed key and determine which direction to move within the form boundaries (explained later).

The character is moved by creating a new point each time in the same direction of the key's value and adding the character_speed to that point.

private void MainCourse_KeyDown(object sender, KeyEventArgs e)
{
switch(e.KeyCode.ToString())
{
case "Up":
...
}
}

Moving Within the Form

To restrict character movement within the form boundaries, I had to first calculate the allowed area. This was performed simply by subtracting one character dimension from one form's dimension and setting that number as a condition to move in the said direction:

case "Right":
if(Character.Location.X < (this.Size.Width - (Character.Width+10)))
Character.Location = new Point(Character.Location.X
+ character_speed, Character.Location.Y);
break;

case "Down":
if(Character.Location.Y < (this.Size.Height - (Character.Height+29)))
Character.Location = new Point(Character.Location.X,
Character.Location.Y + character_speed);
break;

Notice that only Right and Down directions have to be watched. Left and Up are of course already known (0,0).

Shoot!!

I know we have nothing to shoot!! However, please be nice enough to consider this part.

First, we need to initialize the bullet location (in this case, it's the character's location).

Bullet.Location = Character.Location;

Now we set our bullet a location to appear, we can call her to stop being shy and come!!

Bullet.Visible = true;

The next two lines are to have a base for the starting bullet position, otherwise, it won't quit following the character!!

bullet_x = Convert.ToInt32(Character.Location.X);
bullet_y = Convert.ToInt32(Character.Location.Y);

Killing the Killer

Poor little bullet, I think it's the only thing that gets killed in this game!!

Once again, we have to determine the bullet's location in order to terminate it:

if(Bullet.Location.Y >= Bullet.Height)
{
Bullet.Location = new Point(bullet_x,bullet_y);
bullet_y -= bullet_speed;
}

else
kill_bullet();

The bullet is simply killed by stopping its timer and setting its visibility back again to false.

Shoot.Stop();
Bullet.Visible = false;

I think it's about time we look at it all together.

The Code

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using tonysound;

namespace MoveMe
{
    public partial class Game_sample : Form
    {
        int bullet_speed;
        int character_speed;
        int bullet_x;
        int bullet_y;

        public Game_sample()
        {
            InitializeComponent();
            bullet_speed = 4;
            character_speed = 2;
        }

        private void MainCourse_KeyDown(object sender, KeyEventArgs e)
        {
            switch(e.KeyCode.ToString())
            {
                case "Up":
                    if (Character.Location.Y > 1)
			Character.Location = new Point
			(Character.Location.X, Character.Location.Y -
			character_speed);
                    break;

                case "Left":
                    if (Character.Location.X > 1)
			Character.Location = new Point
			(Character.Location.X - character_speed,
			Character.Location.Y);
                    break;

                case "Right":
                    if (Character.Location.X < 
			(this.Size.Width - (Character.Width+10)))
			Character.Location = new Point
			(Character.Location.X + character_speed,
			Character.Location.Y);
                    break;

                case "Down":
                    if (Character.Location.Y < 
			(this.Size.Height - (Character.Height+29)))
		  Character.Location = new Point
			(Character.Location.X, Character.Location.Y +
			character_speed);
                    break;                 

                case "Space":
                    if (!Shoot.Enabled)
                    {
                        Bullet.Location = Character.Location;
                        Bullet.Visible = true;
                        //getting the current location of
		      bullet_x = Convert.ToInt32(Character.Location.X); 
                        //the character to start with
		      bullet_y = Convert.ToInt32(Character.Location.Y); 

                        Sound.Play(Environment.GetFolderPath
			(Environment.SpecialFolder.ProgramFiles)
			+ @"\Windows NT\Pinball\SOUND8.WAV",
			PlaySoundFlags.SND_ASYNC);
                        Shoot.Start();
                    }
                 break;

                case "Escape":
                    btnHide_Options.Text = "&Hide";
                    Options_panel.Location= new Point
			((this.Width - Options_panel.Width) - 15, 5);
                    Options_panel.Visible = true;
		  btnHide_Options.Focus();
                    break;

                default:
                    MessageBox.Show(@"
			Up: Move up
			Right: Move right
			Left: Move left
			Down: Move down
			Space Bar: Fire
			Esc: Game Options","Sample
			game",MessageBoxButtons.OK,
			MessageBoxIcon.Information);
                    break;
            }
        }

        private void kill_bullet()
        {
            Shoot.Stop();
            Bullet.Visible = false;
        }

        private void Shoot_Tick(object sender, EventArgs e)
        {
            if(Bullet.Location.Y >= Bullet.Height)
            {
                Bullet.Location = new Point(bullet_x, bullet_y);
                bullet_y -= bullet_speed;
            }
            else
                kill_bullet();
        }

        private void Close_Options_Click(object sender, EventArgs e)
        {
            bullet_speed = Convert.ToInt32(numBullSpeed.Value);
            character_speed = Convert.ToInt32(numCharSpeed.Value);
            Options_panel.Visible = false;
            this.Focus();
        }

        private void Game_sample_Load(object sender, EventArgs e)
        {
            string strSystem = "system32";
            //replace the music path in the following line to your background music
            Sound.Play(Environment.GetFolderPath
		(Environment.SpecialFolder.System).TrimEnd
		(strSystem.ToCharArray())
		+ @"\Help\Tours\WindowsMediaPlayer\Audio\Wav\wmpaud3.wav",
		PlaySoundFlags.SND_ASYNC);
        }

        private void chMute_CheckedChanged(object sender, EventArgs e)
        {
            if(chMute.Checked)
                Sound.Play(@"Nothing.wav", PlaySoundFlags.SND_ASYNC);
            else
                Sound.Play(Environment.GetFolderPath
		(Environment.SpecialFolder.System)
	       	+ @"\oobe\images\title.wma", PlaySoundFlags.SND_ASYNC);
        }

        private void lnkAbout_LinkClicked
		(object sender, LinkLabelLinkClickedEventArgs e)
        {
            MessageBox.Show("Sample Game\nBy Muammar Yacoob", 
		"The CodeProject", MessageBoxButtons.OK, 
		MessageBoxIcon.Information);
        }

        private void numCharSpeed_ValueChanged(object sender, EventArgs e)
        {
            Sound.Play(Environment.GetFolderPath
		(Environment.SpecialFolder.ProgramFiles) + 
		@"\Windows NT\Pinball\SOUND16.WAV", PlaySoundFlags.SND_ASYNC);
        }

        private void numBullSpeed_ValueChanged(object sender, EventArgs e)
        {
            Sound.Play(Environment.GetFolderPath
		(Environment.SpecialFolder.ProgramFiles) + 
		@"\Windows NT\Pinball\SOUND16.WAV", PlaySoundFlags.SND_ASYNC);
        }
    }
}

Limitations

I couldn't cope up with playing two sounds simultaneously, any similar experience will be highly appreciated.

Notes

In order to decrease the demo size, I've used 2 sound effects and 1 background music from Windows, so make sure they exist on your PC, otherwise replace them with valid ones.