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Playing sound effects in XNA |
At this moment, we have a fully playable game, thanks to all the functionality we’ve added throughout this series of 2D XNA Tutorials. The overall feeling of a game is always MUCH improved once sound effects are added to it, which is what we’re about to do in this chapter.
We’re going to add three simple sound effects: one for the rocket launch, one for a terrain explosion and another one for a cannon explosion. You can download them by clicking on their names in the previous phrase (links don't work yet, for now use 3 sounds of your choice). Make sure you download them to the Content folder of your XNA project, but don’t import them into XNA Game Studio.
Sound effects in XNA are handled a little differently than other assets, such as images. This is done using XAct, a separate program that comes with XNA. This is separate program, as it allows sound artist to add lots of effects to the sound effects, separating this part of the game development from the coding team.
To open XAct, open up your Start menu, and choose Programs -> Microsoft XNA Game Studio 2.0 -> Tools -> Microsoft Cross-Platform Audio Creation Tool (XAct). After XAct has launched, start a new project by opening the File menu and choosing New Project. Browse to the Content folder of your XNA project, call your project xactProject and hit the Save button.
In general, there are 3 types you need to know about in XAct:
When you import a sound file into XAct, this is called a Wave.
From each Wave, you can create multiple Sounds. You can add special effects to Sounds, such as a Doppler effect. So you can add 2 different effects to a Wave by creating 2 Sounds from it, and applying the effects to the Sounds.
You can create playlists from Sounds, which are called Cues. Cues are what we will actually start from within our XNA code.
We first need to create a Wave bank to store our sound files. This is done by right-clicking on the “Wave Banks” entry on the left of your screen, and selecting “New Wave Bank”:
Call the new Wave bank ‘myWaveBank’ and double-click on it. Now it’s time to add our 3 sound files to our Wave bank, which can be done by selecting the “Wave Banks” menu and clicking “Insert Wave Files”:
Browse to the map where you downloaded your 3 sound files, select them (hold Ctrl to select multiple files), and click the Open button. You should see the 3 files are listed in your wave bank in red, meaning they are not yet related to a Sound.
To create Sounds from our Waves, we first need to create a Sound bank by right clicking on “Sound Banks” and selecting “New Sound Bank”. Call it mySoundBank. Move your windows so you can see both your WaveBank and your SoundBank. Now select all 3 Waves, and drag them into the upper area of the Sound Bank. You should see 3 Sounds listed in your Sound Bank, and the Waves are no longer indicated in red.
Finally, select your 3 Sounds, and drag them into the lower part of the Sound Bank, where the Cues are defined. In the end, your Sound Bank window should look like in the image below:
Now all is ready, make sure you open the File menu and hit Save. You can close XAct now if you want.
Now in XNA Game Studio, you should add the XAct project file just like any other asset you would add. Right-Click on the Content entry, click Add -> Existing item and select your newly created .xap file.
To get our sound effect working in our XNA code, we need to add three variables to the top of our code:
AudioEngine audioEngine;
WaveBank waveBank;
SoundBank soundBank;
The AudioEngine should be updated every once in a while, and the other 2 variables are direct links to the banks we created in our XAct project. Fill these 3 variables at the end of our LoadContent method:
audioEngine = new AudioEngine("Content/xactProject.xgs");
waveBank = new WaveBank(audioEngine, "Content/myWaveBank.xwb");
soundBank = new SoundBank(audioEngine, "Content/mySoundBank.xsb");
These 3 files are created by XNA’s Content Pipeline from the .xap file each time you recompile the project. This means that, whenever you make some changes to your audio files, you need to recompile your project.
Let’s make sure we update our AudioEngine at the end of our Update method:
audioEngine.Update();
So much for the preparations, the playing of the audio itself is very easy. The first effect should be started whenever the rocket is launched, which is detected in our ProcessKeyboard method. Add this line to the end of that method, inside the if-block that detects whether the rocket should be launched:
soundBank.PlayCue("launch");
This simply asks your Sound Bank to play the “launch” cue.
The other two effects should be started whenever a detection between the rocket and the terrain or a cannon is detected. So go to our CheckCollisions method, and add this line to the if-block that checks for cannon collisions:
soundBank.PlayCue("hitcannon");
And this line to the if-block that detects terrain collisions:
soundBank.PlayCue("hitterrain");
That’s it! When you run the code, you should hear some sound effect each time you launch a rocket, and when the rocket hits something.
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Hello thanks for the tutorial. I have been enjoyi...Problem: no sound
I have the code correct, but for some reason nothi...Tested
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Our code thus far:
using System;
using System.Collections.Generic;
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.Net;
using Microsoft.Xna.Framework.Storage;
namespace XNAtutorial
{
public struct ParticleData
{
public float BirthTime;
public float MaxAge;
public Vector2 OrginalPosition;
public Vector2 Accelaration;
public Vector2 Direction;
public Vector2 Position;
public float Scaling;
public Color ModColor;
}
public struct PlayerData
{
public Vector2 Position;
public bool IsAlive;
public Color Color;
public float Angle;
public float Power;
}
public class Game1 : Microsoft.Xna.Framework.Game
{
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
GraphicsDevice device;
int screenWidth;
int screenHeight;
Texture2D backgroundTexture;
Texture2D foregroundTexture;
Texture2D carriageTexture;
Texture2D cannonTexture;
Texture2D rocketTexture;
Texture2D smokeTexture;
Texture2D groundTexture;
Texture2D explosionTexture;
SpriteFont font;
PlayerData[] players;
int numberOfPlayers = 4;
float playerScaling;
int currentPlayer = 0;
bool rocketFlying = false;
Vector2 rocketPosition;
Vector2 rocketDirection;
float rocketAngle;
float rocketScaling = 0.1f;
List<ParticleData>
particleList = new List<ParticleData>
();
List<Vector2>
smokeList = new List<Vector2>
(); Random randomizer = new Random();
int[] terrainContour;
Color[,] rocketColorArray;
Color[,] foregroundColorArray;
Color[,] carriageColorArray;
Color[,] cannonColorArray;
Color[,] explosionColorArray;
AudioEngine audioEngine;
WaveBank waveBank;
SoundBank soundBank;
public Game1()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
}
protected override void Initialize()
{
graphics.PreferredBackBufferWidth = 500;
graphics.PreferredBackBufferHeight = 500;
graphics.IsFullScreen = false;
graphics.ApplyChanges();
Window.Title = "Riemer's 2D XNA Tutorial";
base.Initialize();
}
protected override void LoadContent()
{
device = graphics.GraphicsDevice;
spriteBatch = new SpriteBatch(device);
screenWidth = device.PresentationParameters.BackBufferWidth;
screenHeight = device.PresentationParameters.BackBufferHeight;
backgroundTexture = Content.Load<Texture2D>
("background");
carriageTexture = Content.Load<Texture2D>
("carriage");
cannonTexture = Content.Load<Texture2D>
("cannon");
rocketTexture = Content.Load<Texture2D>
("rocket");
smokeTexture = Content.Load<Texture2D>
("smoke");
groundTexture = Content.Load<Texture2D>
("ground");
font = Content.Load<SpriteFont>
("myFont");
explosionTexture = Content.Load<Texture2D>
("explosion");
playerScaling = 40.0f / (float)carriageTexture.Width;
GenerateTerrainContour();
SetUpPlayers();
FlattenTerrainBelowPlayers();
CreateForeground();
rocketColorArray = TextureTo2DArray(rocketTexture);
carriageColorArray = TextureTo2DArray(carriageTexture);
cannonColorArray = TextureTo2DArray(cannonTexture);
explosionColorArray = TextureTo2DArray(explosionTexture);
audioEngine = new AudioEngine("Content/xactProject.xgs");
waveBank = new WaveBank(audioEngine, "Content/myWaveBank.xwb");
soundBank = new SoundBank(audioEngine, "Content/mySoundBank.xsb");
}
private void SetUpPlayers()
{
Color[] playerColors = new Color[10];
playerColors[0] = Color.Red;
playerColors[1] = Color.Green;
playerColors[2] = Color.Blue;
playerColors[3] = Color.Purple;
playerColors[4] = Color.Orange;
playerColors[5] = Color.Indigo;
playerColors[6] = Color.Yellow;
playerColors[7] = Color.SaddleBrown;
playerColors[8] = Color.Tomato;
playerColors[9] = Color.Turquoise;
players = new PlayerData[numberOfPlayers];
for (int i = 0; i < numberOfPlayers; i++)
{
players[i].IsAlive = true;
players[i].Color = playerColors[i];
players[i].Angle = MathHelper.ToRadians(90);
players[i].Power = 100;
players[i].Position = new Vector2();
players[i].Position.X = screenWidth / (numberOfPlayers + 1) * (i + 1);
players[i].Position.Y = terrainContour[(int)players[i].Position.X];
}
}
private void GenerateTerrainContour()
{
terrainContour = new int[screenWidth];
double rand1 = randomizer.NextDouble() + 1;
double rand2 = randomizer.NextDouble() + 2;
double rand3 = randomizer.NextDouble() + 3;
float offset = screenHeight / 2; ;
float peakheight = 100;
float flatness = 70;
for (int x = 0; x < screenWidth; x++)
{
double height = peakheight / rand1 * Math.Sin((float)x / flatness * rand1 + rand1);
height += peakheight / rand2 * Math.Sin((float)x / flatness * rand2 + rand2);
height += peakheight / rand3 * Math.Sin((float)x / flatness * rand3 + rand3);
height += offset;
terrainContour[x] = (int)height;
}
}
private void FlattenTerrainBelowPlayers()
{
foreach (PlayerData player in players)
if (player.IsAlive)
for (int x = 0; x < 40; x++)
terrainContour[(int)player.Position.X + x] = terrainContour[(int)player.Position.X];
}
private void CreateForeground()
{
Color[,] groundColors = TextureTo2DArray(groundTexture);
Color[] foregroundColors = new Color[screenWidth * screenHeight];
for (int x = 0; x < screenWidth; x++)
{
for (int y = 0; y < screenHeight; y++)
{
if (y > terrainContour[x])
foregroundColors[x + y * screenWidth] = groundColors[x % groundTexture.Width, y % groundTexture.Height];
else
foregroundColors[x + y * screenWidth] = Color.TransparentBlack;
}
}
foregroundTexture = new Texture2D(device, screenWidth, screenHeight, 1, TextureUsage.None, SurfaceFormat.Color);
foregroundTexture.SetData(foregroundColors);
foregroundColorArray = TextureTo2DArray(foregroundTexture);
}
private Color[,] TextureTo2DArray(Texture2D texture)
{
Color[] colors1D = new Color[texture.Width * texture.Height];
texture.GetData(colors1D);
Color[,] colors2D = new Color[texture.Width, texture.Height];
for (int x = 0; x < texture.Width; x++)
for (int y = 0; y < texture.Height; y++)
colors2D[x, y] = colors1D[x + y * texture.Width];
return colors2D;
}
protected override void UnloadContent()
{
}
protected override void Update(GameTime gameTime)
{
if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
this.Exit();
if ((!rocketFlying) && (particleList.Count == 0))
ProcessKeyboard();
if (rocketFlying)
{
UpdateRocket();
CheckCollisions(gameTime);
}
if (particleList.Count > 0)
UpdateParticles(gameTime);
audioEngine.Update();
base.Update(gameTime);
}
private void ProcessKeyboard()
{
KeyboardState keybState = Keyboard.GetState();
if (keybState.IsKeyDown(Keys.Left))
players[currentPlayer].Angle -= 0.01f;
if (keybState.IsKeyDown(Keys.Right))
players[currentPlayer].Angle += 0.01f;
if (players[currentPlayer].Angle > MathHelper.PiOver2)
players[currentPlayer].Angle = -MathHelper.PiOver2;
if (players[currentPlayer].Angle < -MathHelper.PiOver2)
players[currentPlayer].Angle = MathHelper.PiOver2;
if (keybState.IsKeyDown(Keys.Down))
players[currentPlayer].Power -= 1;
if (keybState.IsKeyDown(Keys.Up))
players[currentPlayer].Power += 1;
if (keybState.IsKeyDown(Keys.PageDown))
players[currentPlayer].Power -= 20;
if (keybState.IsKeyDown(Keys.PageUp))
players[currentPlayer].Power += 20;
if (players[currentPlayer].Power > 1000)
players[currentPlayer].Power = 1000;
if (players[currentPlayer].Power < 0)
players[currentPlayer].Power = 0;
if (keybState.IsKeyDown(Keys.Enter) || keybState.IsKeyDown(Keys.Space))
{
rocketFlying = true;
rocketPosition = players[currentPlayer].Position;
rocketPosition.X += 20;
rocketPosition.Y -= 10;
rocketAngle = players[currentPlayer].Angle;
Vector2 up = new Vector2(0, -1);
Matrix rotMatrix = Matrix.CreateRotationZ(rocketAngle);
rocketDirection = Vector2.Transform(up, rotMatrix);
rocketDirection *= players[currentPlayer].Power / 50.0f;
soundBank.PlayCue("hitcannon");
}
}
private void UpdateRocket()
{
if (rocketFlying)
{
Vector2 gravity = new Vector2(0, 1);
rocketDirection += gravity / 10.0f;
rocketPosition += rocketDirection;
rocketAngle = (float)Math.Atan2(rocketDirection.X, -rocketDirection.Y);
for (int i = 0; i < 5; i++)
{
Vector2 smokePos = rocketPosition;
smokePos.X += randomizer.Next(10) - 5;
smokePos.Y += randomizer.Next(10) - 5;
smokeList.Add(smokePos);
}
}
}
private Vector2 TexturesCollide(Color[,] tex1, Matrix mat1, Color[,] tex2, Matrix mat2)
{
Matrix mat1to2 = mat1 * Matrix.Invert(mat2);
int width1 = tex1.GetLength(0);
int height1 = tex1.GetLength(1);
int width2 = tex2.GetLength(0);
int height2 = tex2.GetLength(1);
for (int x1 = 0; x1 < width1; x1++)
{
for (int y1 = 0; y1 < height1; y1++)
{
Vector2 pos1 = new Vector2(x1, y1);
Vector2 pos2 = Vector2.Transform(pos1, mat1to2);
int x2 = (int)pos2.X;
int y2 = (int)pos2.Y;
if ((x2 >= 0) && (x2 < width2))
{
if ((y2 >= 0) && (y2 < height2))
{
if (tex1[x1, y1].A > 0)
{
if (tex2[x2, y2].A > 0)
{
Vector2 screenPos = Vector2.Transform(pos1, mat1);
return screenPos;
}
}
}
}
}
}
return new Vector2(-1, -1);
}
private Vector2 CheckTerrainCollision()
{
Matrix rocketMat = Matrix.CreateTranslation(-42, -240, 0) * Matrix.CreateRotationZ(rocketAngle) * Matrix.CreateScale(rocketScaling) * Matrix.CreateTranslation(rocketPosition.X, rocketPosition.Y, 0);
Matrix terrainMat = Matrix.Identity;
Vector2 terrainCollisionPoint = TexturesCollide(rocketColorArray, rocketMat, foregroundColorArray, terrainMat);
return terrainCollisionPoint;
}
private Vector2 CheckPlayersCollision()
{
Matrix rocketMat = Matrix.CreateTranslation(-42, -240, 0) * Matrix.CreateRotationZ(rocketAngle) * Matrix.CreateScale(rocketScaling) * Matrix.CreateTranslation(rocketPosition.X, rocketPosition.Y, 0);
for (int i = 0; i < numberOfPlayers; i++)
{
PlayerData player = players[i];
if (player.IsAlive)
{
if (i != currentPlayer)
{
int xPos = (int)player.Position.X;
int yPos = (int)player.Position.Y;
Matrix carriageMat = Matrix.CreateTranslation(0, -carriageTexture.Height, 0) * Matrix.CreateScale(playerScaling) * Matrix.CreateTranslation(xPos, yPos, 0);
Vector2 carriageCollisionPoint = TexturesCollide(carriageColorArray, carriageMat, rocketColorArray, rocketMat);
if (carriageCollisionPoint.X > -1)
{
players[i].IsAlive = false;
return carriageCollisionPoint;
}
Matrix cannonMat = Matrix.CreateTranslation(-11, -50, 0) * Matrix.CreateRotationZ(player.Angle) * Matrix.CreateScale(playerScaling) * Matrix.CreateTranslation(xPos + 20, yPos - 10, 0);
Vector2 cannonCollisionPoint = TexturesCollide(cannonColorArray, cannonMat, rocketColorArray, rocketMat);
if (cannonCollisionPoint.X > -1)
{
players[i].IsAlive = false;
return cannonCollisionPoint;
}
}
}
}
return new Vector2(-1, -1);
}
private bool CheckOutOfScreen()
{
bool rocketOutOfScreen = rocketPosition.Y > screenHeight;
rocketOutOfScreen |= rocketPosition.X < 0;
rocketOutOfScreen |= rocketPosition.X > screenWidth;
return rocketOutOfScreen;
}
private void CheckCollisions(GameTime gameTime)
{
Vector2 terrainCollisionPoint = CheckTerrainCollision();
Vector2 playerCollisionPoint = CheckPlayersCollision();
bool rocketOutOfScreen = CheckOutOfScreen();
if (playerCollisionPoint.X > -1)
{
rocketFlying = false;
smokeList = new List<Vector2>
(); NextPlayer();
AddExplosion(playerCollisionPoint, 10, 80.0f, 2000.0f, gameTime);
soundBank.PlayCue("hitcannon");
}
if (terrainCollisionPoint.X > -1)
{
rocketFlying = false;
smokeList = new List<Vector2>
(); NextPlayer();
AddExplosion(terrainCollisionPoint, 4, 30.0f, 1000.0f, gameTime);
soundBank.PlayCue("hitterrain");
}
if (rocketOutOfScreen)
{
rocketFlying = false;
smokeList = new List<Vector2>
(); NextPlayer();
}
}
private void NextPlayer()
{
currentPlayer = currentPlayer + 1;
currentPlayer = currentPlayer % numberOfPlayers;
while (!players[currentPlayer].IsAlive)
{
currentPlayer = ++currentPlayer % numberOfPlayers;
}
}
private void AddExplosion(Vector2 explosionPos, int numberOfParticles, float size, float maxAge, GameTime gameTime)
{
for (int i = 0; i < numberOfParticles; i++)
AddExplosionParticle(explosionPos, size, maxAge, gameTime);
float rotation = (float)randomizer.Next(10);
Matrix mat = Matrix.CreateTranslation(-explosionTexture.Width / 2, -explosionTexture.Height / 2, 0) * Matrix.CreateRotationZ(rotation) * Matrix.CreateScale(size / (float)explosionTexture.Width * 2.0f) * Matrix.CreateTranslation(explosionPos.X, explosionPos.Y, 0);
AddCrater(explosionColorArray, mat);
for (int i = 0; i < players.Length; i++)
players[i].Position.Y = terrainContour[(int)players[i].Position.X];
FlattenTerrainBelowPlayers();
CreateForeground();
}
private void AddExplosionParticle(Vector2 explosionPos, float explosionSize, float maxAge, GameTime gameTime)
{
ParticleData particle = new ParticleData();
particle.OrginalPosition = explosionPos;
particle.Position = particle.OrginalPosition;
particle.BirthTime = (float)gameTime.TotalGameTime.TotalMilliseconds;
particle.MaxAge = maxAge;
particle.Scaling = 0.25f;
particle.ModColor = Color.White;
float particleDistance = (float)randomizer.NextDouble() * explosionSize;
Vector2 displacement = new Vector2(particleDistance, 0);
float angle = MathHelper.ToRadians(randomizer.Next(360));
displacement = Vector2.Transform(displacement, Matrix.CreateRotationZ(angle));
particle.Direction = displacement * 2.0f;
particle.Accelaration = -particle.Direction;
particleList.Add(particle);
}
private void UpdateParticles(GameTime gameTime)
{
float now = (float)gameTime.TotalGameTime.TotalMilliseconds;
for (int i = particleList.Count - 1; i >= 0; i--)
{
ParticleData particle = particleList[i];
float timeAlive = now - particle.BirthTime;
if (timeAlive > particle.MaxAge)
{
particleList.RemoveAt(i);
}
else
{
float relAge = timeAlive / particle.MaxAge;
particle.Position = 0.5f * particle.Accelaration * relAge * relAge + particle.Direction * relAge + particle.OrginalPosition;
float invAge = 1.0f - relAge;
particle.ModColor = new Color(new Vector4(invAge, invAge, invAge, invAge));
Vector2 positionFromCenter = particle.Position - particle.OrginalPosition;
float distance = positionFromCenter.Length();
particle.Scaling = (50.0f + distance) / 200.0f;
particleList[i] = particle;
}
}
}
private void AddCrater(Color[,] tex, Matrix mat)
{
int width = tex.GetLength(0);
int height = tex.GetLength(1);
for (int x = 0; x < width; x++)
{
for (int y = 0; y < height; y++)
{
if (tex[x, y].R > 10)
{
Vector2 imagePos = new Vector2(x, y);
Vector2 screenPos = Vector2.Transform(imagePos, mat);
int screenX = (int)screenPos.X;
int screenY = (int)screenPos.Y;
if ((screenX) > 0 && (screenX < screenWidth))
if (terrainContour[screenX] < screenY)
terrainContour[screenX] = screenY;
}
}
}
}
protected override void Draw(GameTime gameTime)
{
graphics.GraphicsDevice.Clear(Color.CornflowerBlue);
spriteBatch.Begin();
DrawScenery();
DrawPlayers();
DrawText();
DrawRocket();
DrawSmoke();
spriteBatch.End();
spriteBatch.Begin(SpriteBlendMode.Additive, SpriteSortMode.Deferred, SaveStateMode.None);
DrawExplosion();
spriteBatch.End();
base.Draw(gameTime);
}
private void DrawScenery()
{
Rectangle screenRectangle = new Rectangle(0, 0, screenWidth, screenHeight);
spriteBatch.Draw(backgroundTexture, screenRectangle, Color.White);
spriteBatch.Draw(foregroundTexture, screenRectangle, Color.White);
}
private void DrawPlayers()
{
foreach (PlayerData player in players)
{
if (player.IsAlive)
{
int xPos = (int)player.Position.X;
int yPos = (int)player.Position.Y;
Vector2 cannonOrigin = new Vector2(11, 50);
spriteBatch.Draw(cannonTexture, new Vector2(xPos + 20, yPos - 10), null, player.Color, player.Angle, cannonOrigin, playerScaling, SpriteEffects.None, 1);
spriteBatch.Draw(carriageTexture, player.Position, null, player.Color, 0, new Vector2(0, carriageTexture.Height), playerScaling, SpriteEffects.None, 0);
}
}
}
private void DrawText()
{
PlayerData player = players[currentPlayer];
int currentAngle = (int)MathHelper.ToDegrees(player.Angle);
spriteBatch.DrawString(font, "Cannon angle: " + currentAngle.ToString(), new Vector2(20, 20), player.Color);
spriteBatch.DrawString(font, "Cannon power: " + player.Power.ToString(), new Vector2(20, 45), player.Color);
}
private void DrawRocket()
{
if (rocketFlying)
spriteBatch.Draw(rocketTexture, rocketPosition, null, players[currentPlayer].Color, rocketAngle, new Vector2(42, 240), rocketScaling, SpriteEffects.None, 1);
}
private void DrawSmoke()
{
foreach (Vector2 smokePos in smokeList)
spriteBatch.Draw(smokeTexture, smokePos, null, Color.White, 0, new Vector2(40, 35), 0.2f, SpriteEffects.None, 1);
}
private void DrawExplosion()
{
for (int i = 0; i < particleList.Count; i++)
{
ParticleData particle = particleList[i];
spriteBatch.Draw(explosionTexture, particle.Position, null, particle.ModColor, i, new Vector2(256, 256), particle.Scaling, SpriteEffects.None, 1);
}
}
}
}
- Website design & XNA + DirectX code : Riemer Grootjans -
©2003 - 2008 Riemer Grootjans
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