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Monogame shader doesn't draw anything

I'm brand new to working with shaders and I'm trying to learn how to use them with Monogame. I've been reading a few tutorials online about them and I'm already running into problems. It may be that the tutorials are outdated? When I apply the effect I just get a blank, cornflowerblue, screen.
#if OPENGL
#define SV_POSITION POSITION
#define VS_SHADERMODEL vs_3_0
#define PS_SHADERMODEL ps_3_0
#else
#define VS_SHADERMODEL vs_4_0_level_9_1
#define PS_SHADERMODEL ps_4_0_level_9_1
#endif
texture ScreenTexture;
sampler TextureSampler = sampler_state {
Texture = <ScreenTexture>;
};
float4 PixelShaderFunction(float2 TextureCoordinate : TEXCOORD0) : COLOR0{
float4 color = tex2D(TextureSampler, TextureCoordinate);
return color;
}
technique Plain {
pass Pass1 {
PixelShader = compile PS_SHADERMODEL PixelShaderFunction();
}
};
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
namespace ShaderTest {
/// <summary>
/// This is the main type for your game.
/// </summary>
public class Game1 : Game {
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
Effect shader1;
Texture2D peach;
public Game1() {
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
}
/// <summary>
/// Allows the game to perform any initialization it needs to before starting to run.
/// This is where it can query for any required services and load any non-graphic
/// related content. Calling base.Initialize will enumerate through any components
/// and initialize them as well.
/// </summary>
protected override void Initialize() {
// TODO: Add your initialization logic here
base.Initialize();
}
/// <summary>
/// LoadContent will be called once per game and is the place to load
/// all of your content.
/// </summary>
protected override void LoadContent() {
// Create a new SpriteBatch, which can be used to draw textures.
spriteBatch = new SpriteBatch(GraphicsDevice);
shader1 = Content.Load<Effect>("shader1");
peach = Content.Load<Texture2D>("peach");
}
/// <summary>
/// UnloadContent will be called once per game and is the place to unload
/// game-specific content.
/// </summary>
protected override void UnloadContent() {
// TODO: Unload any non ContentManager content here
}
/// <summary>
/// Allows the game to run logic such as updating the world,
/// checking for collisions, gathering input, and playing audio.
/// </summary>
/// <param name="gameTime">Provides a snapshot of timing values.</param>
protected override void Update(GameTime gameTime) {
if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed || Keyboard.GetState().IsKeyDown(Keys.Escape))
Exit();
// TODO: Add your update logic here
base.Update(gameTime);
}
/// <summary>
/// This is called when the game should draw itself.
/// </summary>
/// <param name="gameTime">Provides a snapshot of timing values.</param>
protected override void Draw(GameTime gameTime) {
GraphicsDevice.Clear(Color.CornflowerBlue);
spriteBatch.Begin(SpriteSortMode.Immediate, BlendState.AlphaBlend);
shader1.CurrentTechnique.Passes[0].Apply();
spriteBatch.Draw(peach, new Vector2(0, 0), Color.White);
spriteBatch.End();
base.Draw(gameTime);
}
}
}
without shader:
with shader:

XNA objects not drawing

So I have a problem that I cant figure out, and that is drawing objects into my main Game1 class from a class of drawablegamecomponent.
I'v been playing around with it for a bit and looking at other examples, but can't figure out the issue. There isn't much code as it is, so I'll just post the two classes I have, the main class Game1 and the class I want to draw, Balloon.
The error is in the draw method I get this...
An unhandled exception of type 'System.NullReferenceException' occurred in Burst.exe
Additional information: Object reference not set to an instance of an object.
Main Class.
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 Burst
{
/// <summary>
/// This is the main type for your game
/// </summary>
public class Game1 : Microsoft.Xna.Framework.Game
{
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
Rectangle bounds;
Balloon ball;
Diamond dia;
public Game1()
{
graphics = new GraphicsDeviceManager(this);
graphics.PreferredBackBufferWidth = 1152;
graphics.PreferredBackBufferHeight = 648;
Content.RootDirectory = "Content";
bounds = new Rectangle(0, 0, graphics.PreferredBackBufferWidth, graphics.PreferredBackBufferHeight);
ball = new Balloon(bounds, 1, this, spriteBatch);
dia = new Diamond(bounds, new Vector2(200, 200), this, spriteBatch);
}
/// <summary>
/// Allows the game to perform any initialization it needs to before starting to run.
/// This is where it can query for any required services and load any non-graphic
/// related content. Calling base.Initialize will enumerate through any components
/// and initialize them as well.
/// </summary>
protected override void Initialize()
{
// TODO: Add your initialization logic here
base.Initialize();
}
/// <summary>
/// LoadContent will be called once per game and is the place to load
/// all of your content.
/// </summary>
protected override void LoadContent()
{
// Create a new SpriteBatch, which can be used to draw textures.
spriteBatch = new SpriteBatch(GraphicsDevice);
// TODO: use this.Content to load your game content here
}
/// <summary>
/// UnloadContent will be called once per game and is the place to unload
/// all content.
/// </summary>
protected override void UnloadContent()
{
// TODO: Unload any non ContentManager content here
}
/// <summary>
/// Allows the game to run logic such as updating the world,
/// checking for collisions, gathering input, and playing audio.
/// </summary>
/// <param name="gameTime">Provides a snapshot of timing values.</param>
protected override void Update(GameTime gameTime)
{
// Allows the game to exit
if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
this.Exit();
// TODO: Add your update logic here
ball.Update();
base.Update(gameTime);
}
/// <summary>
/// This is called when the game should draw itself.
/// </summary>
/// <param name="gameTime">Provides a snapshot of timing values.</param>
protected override void Draw(GameTime gameTime)
{
GraphicsDevice.Clear(Color.CornflowerBlue);
spriteBatch.Begin();
// TODO: Add your drawing code here
ball.Draw(gameTime);
dia.Draw(gameTime);
spriteBatch.End();
base.Draw(gameTime);
}
}
}
Balloon Class:
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Burst
{
public class Balloon : Microsoft.Xna.Framework.DrawableGameComponent
{
Vector2 position;
Vector2 motion;
Texture2D texture;
Rectangle bounds;
Rectangle screenBounds;
Game game;
SpriteBatch spriteBatch;
float balloonSpeed = 4;
int colour = 0;
public Balloon(Rectangle screenBounds, int colour, Game game, SpriteBatch spriteBatch) : base (game)
{
this.colour = colour;
this.game = game;
this.spriteBatch = spriteBatch;
this.screenBounds = screenBounds;
this.position = new Vector2(200,200);
}
protected override void LoadContent()
{
switch (colour)
{
case 1: texture = Game.Content.Load<Texture2D>("Images/BlueBalloon");
break;
case 2: texture = Game.Content.Load<Texture2D>("Images/GreenBalloon");
break;
case 3: texture = Game.Content.Load<Texture2D>("Images/RedBalloon");
break;
case 4: texture = Game.Content.Load<Texture2D>("Images/YellowBalloon");
break;
case 5: texture = Game.Content.Load<Texture2D>("Images/PurpleBalloon");
break;
}
}
public Rectangle Bounds
{
get
{
bounds.X = (int)position.X;
bounds.Y = (int)position.Y;
return bounds;
}
}
public void Update()
{
position += motion * balloonSpeed;
}
private void CheckWallColision()
{
if (position.X < 0)
{
position.X = 0;
motion.X *= -1;
}
if (position.X + texture.Width > screenBounds.Width)
{
position.X = screenBounds.Width - texture.Width;
motion.X *= -1;
}
if (position.Y < 0)
{
position.Y = 0;
motion.Y *= -1;
}
if (position.Y + texture.Height > screenBounds.Height)
{
position.Y = screenBounds.Height - texture.Height;
motion.Y *= -1;
}
}
public void SetStartPosition()
{
Random rand = new Random();
motion = new Vector2(rand.Next(2, 6), -rand.Next(2, 6));
motion.Normalize();
position = new Vector2(200, 300);
}
public void Draw()
{
spriteBatch.Draw(texture, position, Color.White);
}
}
}

"spriteBatch" == null when you create objects "ball" and "dia".
You need move this code:
bounds = new Rectangle(0, 0, graphics.PreferredBackBufferWidth, graphics.PreferredBackBufferHeight);
ball = new Balloon(bounds, 1, this, spriteBatch);
dia = new Diamond(bounds, new Vector2(200, 200), this, spriteBatch);
to method "LoadContent". After creating "spriteBatch".

Detecting history of keystrokes in c#

So currently, I am a newb starting coding in c#. I started making a space game akin to space invaders and ran into an issue, in the draw method, I set it to draw my bullet and head upward on the string as soon as i hit space. But the problem was as soon as I let go of space, my bullet disappeared. I made a work around where as soon as the bullet left the screen it would teleport to the ship. Is there anyway to make the game check if the button has been pressed in the past and make the bullet keep moving until i want it to disappear.
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 Spaceteroids
{
/// <summary>
/// This is the main type for your game
/// </summary>
public class Game1 : Microsoft.Xna.Framework.Game
{
Texture2D spriteSheet;
Texture2D laser;
Texture2D Enemyship;
spriteAnimation loading;
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
KeyboardState currentKeyboard;
KeyboardState oldKeyboard;
PlayerShip character;
Rectangle characterRectangle;
Bullet bullet;
Bullet bullet2;
bool heightCheck;
public Game1()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
}
/// <summary>
/// Allows the game to perform any initialization it needs to before starting to run.
/// This is where it can query for any required services and load any non-graphic
/// related content. Calling base.Initialize will enumerate through any components
/// and initialize them as well.
/// </summary>
protected override void Initialize()
{
// TODO: Add your initialization logic here
currentKeyboard = new KeyboardState();
oldKeyboard = new KeyboardState();
//characterRectangle = new Rectangle((int)character.Position.X,(int)character.Position.Y, spriteSheet.Width / 4, spriteSheet.Height);
character = new PlayerShip(new Vector2(GraphicsDevice.Viewport.Width / 2, GraphicsDevice.Viewport.Height - 40));
bullet = new Bullet(new Vector2(character.Position.X, character.Position.Y - 20));
base.Initialize();
}
void Movement()
{
if (IsHeld(Keys.A))
{
character.xSpeed = -6;
}
else if (IsHeld(Keys.D))
{
character.xSpeed = 6;
}
else
{
character.xSpeed = 0;
}
}
void Collision()
{
if (character.Position.X < 0)
{
character.Position.X = 0;
}
else if (character.Position.X + (spriteSheet.Width/4) > graphics.GraphicsDevice.Viewport.Width)
{
character.Position.X = graphics.GraphicsDevice.Viewport.Width - (spriteSheet.Width/4) ;
}
}
/// <summary>
/// LoadContent will be called once per game and is the place to load
/// all of your content.
/// </summary>
protected override void LoadContent()
{
laser = Content.Load<Texture2D>("Laser");
Enemyship = Content.Load<Texture2D>("EnemyShip");
spriteSheet = Content.Load<Texture2D>("shipSpriteSheet");
spriteBatch = new SpriteBatch(GraphicsDevice);
loading = new spriteAnimation(Content.Load<Texture2D>("shipSpriteSheet"), 4);
loading.Position = new Vector2(character.Position.X);
loading.IsLooping = true;
loading.FramesPerSecond = 30;
// TODO: use this.Content to load your game content here
}
/// <summary>
/// UnloadContent will be called once per game and is the place to unload
/// all content.
/// </summary>
protected override void UnloadContent()
{
// TODO: Unload any non ContentManager content here
}
/// <summary>
/// Allows the game to run logic such as updating the world,
/// checking for collisions, gathering input, and playing audio.
/// </summary>
/// <param name="gameTime">Provides a snapshot of timing values.</param>
protected override void Update(GameTime gameTime)
{
bullet.Position.X = character.Position.X;
currentKeyboard = Keyboard.GetState();
oldKeyboard = currentKeyboard;
loading.Update(gameTime, character);
bullet.ySpeed = -10;
bullet.UpdateBullet();
Collision();
Movement();
if (NotPressed(Keys.Space))
{
bullet.Position.Y = character.Position.Y - 15;
}
if (bullet.Position.Y < 0)
{
bullet.Position.Y = character.Position.Y - 15;
}
character.UpdateShip();
// TODO: Add your update logic here
base.Update(gameTime);
}
/// <summary>
/// This is called when the game should draw itself.
/// </summary>
/// <param name="gameTime">Provides a snapshot of timing values.</param>
protected override void Draw(GameTime gameTime)
{
GraphicsDevice.Clear(Color.Black);
spriteBatch.Begin();
spriteBatch.Draw(laser, new Vector2(bullet.Position.X, bullet.Position.Y), Color.White);
loading.Draw(spriteBatch);
spriteBatch.End();
base.Draw(gameTime);
}
public bool IsHeld(Keys key)
{
if (currentKeyboard.IsKeyDown(key))
{
return true;
}
else
{
return false;
}
}
public bool IsReleased(Keys key)
{
if (currentKeyboard.IsKeyUp(key) && oldKeyboard.IsKeyDown(key))
{
return true;
}
else
{
return false;
}
}
public bool JustPressed(Keys key)
{
if (currentKeyboard.IsKeyDown(key) && oldKeyboard.IsKeyUp(key))
{
return true;
}
else
{
return false;
}
}
public bool NotPressed(Keys key)
{
if (IsHeld(key) != true)
{
return true;
}
else
{
return false;
}
}
public bool HasBeenPressed(Keys key)
{
if (oldKeyboard.IsKeyDown(key))
{
return true;
}
else return false;
}
}
}
If you need any other information, feel free to ask.

No, there is nothing in XNA to track keystroke history (or anywhere else either). You have to do it yourself.
The usual solution to your problem is to maintain state on an object that represents the bullet. The keystroke may go away, but the object remains and keeps the bullet visible and moving until it is destroyed. You appear to have that state in your bullet object, so the likelihood is you just have logic errors in when to update it.
The problem is not instantly obvious from a quick read but your handling of keyboard state seems overly complex. All you need is key down and key up. All the rest you should track for yourself.

Sound Buttons don't play sound

I'm making a program where one clicks buttons to create sound, like those instant button apps. But when I click the button, it won't play any sound. I don't know why either.
All my "Build" debugs are succeeding too.
These are my classes:
Game1.cs:
public class Game1 : Microsoft.Xna.Framework.Game
{
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
Texture2D Background;
Button button;
public Game1()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
this.Window.Title = "Bengt Slår På Knappar";
graphics.PreferredBackBufferHeight = 720;
graphics.PreferredBackBufferWidth = 1280;
IsMouseVisible = true;
}
/// <summary>
/// Allows the game to perform any initialization it needs to before starting to run.
/// This is where it can query for any required services and load any non-graphic
/// related content. Calling base.Initialize will enumerate through any components
/// and initialize them as well.
/// </summary>
protected override void Initialize()
{
// TODO: Add your initialization logic here
base.Initialize();
}
/// <summary>
/// LoadContent will be called once per game and is the place to load
/// all of your content.
/// </summary>
protected override void LoadContent()
{
Background = Content.Load<Texture2D>("bengtbakgrund");
Texture2D Btexture = Content.Load<Texture2D>("Button");
SoundEffect dundundun = Content.Load<SoundEffect>("DUN DUN DUN");
button = new Button(dundundun, Btexture);
spriteBatch = new SpriteBatch(GraphicsDevice);
}
/// <summary>
/// UnloadContent will be called once per game and is the place to unload
/// all content.
/// </summary>
protected override void UnloadContent()
{
// TODO: Unload any non ContentManager content here
}
/// <summary>
/// Allows the game to run logic such as updating the world,
/// checking for collisions, gathering input, and playing audio.
/// </summary>
/// <param name="gameTime">Provides a snapshot of timing values.</param>
protected override void Update(GameTime gameTime)
{
// Allows the game to exit
if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
this.Exit();
Rectangle mouseRect = new Rectangle(Mouse.GetState().X, Mouse.GetState().Y, 10, 10);
MouseState mouseState = Mouse.GetState();
if (mouseRect.Intersects(button.rect) && mouseState.LeftButton == ButtonState.Pressed)
{
button.MySound.Play();
}
base.Update(gameTime);
}
protected override void Draw(GameTime gameTime)
{
GraphicsDevice.Clear(Color.CornflowerBlue);
spriteBatch.Begin();
spriteBatch.Draw(Background, new Vector2(0,0), Color.White);
button.Draw(spriteBatch, new Vector2(300, 300));
spriteBatch.End();
base.Draw(gameTime);
}
}
Button.cs:
public class Button
{
Texture2D Texture { get; set; }
public SoundEffect MySound { get; set; }
public Rectangle rect;
public Button(SoundEffect mySound, Texture2D texture)
{
MySound = mySound;
Texture = texture;
}
public void LoadContent(ContentManager Content)
{
}
public void Update(GameTime gameTime)
{
}
public void Draw(SpriteBatch spriteBatch, Vector2 location)
{
Rectangle rect = new Rectangle((int)0, (int)0, Texture.Width, Texture.Height);
spriteBatch.Draw(Texture, location, Color.White);
}
}
What I'm trying to do is have one base button class, so if you want to add a new button with a sound, you just write: button = new Button(//sound effect, //texture);
But I can't get it to work. Any help would be appreciated.

The way you are handling your buttons position is incorrect, and I am not sure how it compiles. In your draw method you define a local variable rect that already exists. And even if it did, you are not taking into account the actual position of the button.
I think you could also move your button update logic into the class, so I will propose what I think you need to do.
public class Button
{
//Properties
private Texture2D Texture { get; set; }
private SoundEffect Sound { get; set; }
private Rectangle Rectangle { get; set; }
public Button(SoundEffect sound, Texture2D texture, Rectangle position)
{
Sound = sound;
Texture = texture;
Rectangle = position;
}
public void Update(GameTime gameTime, MouseState mouseState)
{
//If mouse is down and the rectangle contains the mouse point (Better for points than Intersect())
if (mouseState.LeftButton == ButtonState.Pressed && Rectangle.Contains(new Point(mouseState.X,mouseState.Y))
{
Sound.Play()
}
}
public void Draw(SpriteBatch spriteBatch)
{
spriteBatch.Draw(Texture, rectangle, Color.White);
}
}
You can then just do button.Update(Mouse.GetState()) (Or use another MouseState if you have one already)
It appears there was some confusion with the drawing position, vs the actual position of the button (in the draw method)
You need to make sure the button is aware of its position on the screen, as well as it's width and height.
button = new Button(dundundun, Btexture, new Rectangle(300, 300, Btexture.Width, Btexture.Height);
That will make the button at 300,500 and be the default size for the texture, now your sound button is done done done :)
I would also recommend learning and using event handlers, so you can add events for the button such as button.Click += //Do something easily

lander of game, not landing on the landing pad but passing through

i want to get the lander of this xna game to successfully touchdown on the landing pad, and then play the sound, however, it passes right through and the sound still plays. the complete code for this is:
namespace MoonLander
{
/// <summary>
/// This is the main type for your game
/// </summary>
public class BasicLunarLander : Microsoft.Xna.Framework.Game
{
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
SoundEffectInstance EndGameSoundInstance;
Texture2D BackgroundImage;
Texture2D LandingImage;
SoundEffect EndGameSound;
int LanderPosX;
int LanderPosY;
Texture2D LandingPadImage;
public BasicLunarLander()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
}
/// <summary>
/// Allows the game to perform any initialization it needs to before starting to run.
/// This is where it can query for any required services and load any non-graphic
/// related content. Calling base.Initialize will enumerate through any components
/// and initialize them as well.
/// </summary>
protected override void Initialize()
{
// TODO: Add your initialization logic here
LanderPosX = 100;
LanderPosY = 0;
base.Initialize();
}
/// <summary>
/// LoadContent will be called once per game and is the place to load
/// all of your content.
/// </summary>
protected override void LoadContent()
{
// Create a new SpriteBatch, which can be used to draw textures.
spriteBatch = new SpriteBatch(GraphicsDevice);
// TODO: use this.Content to load your game content here
BackgroundImage = Content.Load<Texture2D>("background");
LandingImage = Content.Load<Texture2D>("lander");
LandingPadImage = Content.Load<Texture2D>("landingpad");
EndGameSound = Content.Load<SoundEffect>("crowdcheer");
EndGameSoundInstance = EndGameSound.CreateInstance();
}
/// <summary>
/// UnloadContent will be called once per game and is the place to unload
/// all content.
/// </summary>
protected override void UnloadContent()
{
// TODO: Unload any non ContentManager content here
}
/// <summary>
/// Allows the game to run logic such as updating the world,
/// checking for collisions, gathering input, and playing audio.
/// </summary>
/// <param name="gameTime">Provides a snapshot of timing values.</param>
protected override void Update(GameTime gameTime)
{
// Allows the game to exit
if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
this.Exit();
if (Keyboard.GetState().IsKeyDown(Keys.Down))
{
LanderPosY = LanderPosY + 2;
}
if (Keyboard.GetState().IsKeyDown(Keys.Up))
{
LanderPosY = LanderPosY - 2;
}
if (Keyboard.GetState().IsKeyDown(Keys.Left))
{
LanderPosX = LanderPosX - 2;
}
if (Keyboard.GetState().IsKeyDown(Keys.Right))
{
LanderPosX = LanderPosX + 2;
}
// TODO: Add your update logic here
Rectangle rectLander = new Rectangle(LanderPosX, LanderPosY, LandingImage.Width, LandingImage.Height);
Rectangle rectLandingPad = new Rectangle(350, 500, LandingPadImage.Width, LandingPadImage.Height);
if (rectLander.Intersects(rectLandingPad))
{
EndGameSoundInstance.Play();
}
base.Update(gameTime);
}
/// <summary>
/// This is called when the game should draw itself.
/// </summary>
/// <param name="gameTime">Provides a snapshot of timing values.</param>
protected override void Draw(GameTime gameTime)
{
// TODO: Add your drawing code here
spriteBatch.Begin();
spriteBatch.Draw(BackgroundImage, Vector2.Zero, Color.White);
spriteBatch.Draw(LandingImage, new Vector2(LanderPosX, LanderPosY), Color.White);
spriteBatch.Draw(LandingPadImage, new Vector2(350,500), Color.White);
spriteBatch.End();
base.Draw(gameTime);
}
}
}
Hope you can help me with this issue, thank you all for your time.

Its because you're not doing anything about preventing movement after the lander has landed (the condition has been met). The sound plays of course, because that is what you did code.
Add a variable detecting if it has landed and declare it inside your class
bool _hasLanded = false;
then wrap the key detection in your update method (for up, down, left and right keys) inside and if:
if(!_hasLanded)
{
//keypresses go here
}
and finally, inside your if where you check to see if the rectangles intersect, add
_hasLanded = true;
That should prevent you from being able to move the lander once it has touched the landing pad.