Drawing a filled Rectangle in Xna 2.0 OR 3.0 without a existing saved texture

Now i’ve been looking around and a question a few seem to have is how to generate a filled rectangle in XNA. Well the simple truth is that XNA doesnt provide these methods directly to you But it does allow you to get or set the color data of a Texture. So that is exactly what were going to do.Texture2D’s can be created whenever you want without a content manage unlike the Model class does. So first create a Textured2D variable wherever you want preferably above the constructor so that you can immediatly can go to it without searching through tons of lines.
So you should have something like this:

Texture2D myTexture;
public Game1()
{
...
}

Now with that done lets move onto creating a method that will return a valid Texture2D


private Texture2D CreateRectangle(int width,int height)
{
Texture2D rectangleTexture = new Texture2D(GraphicsDevice, width, height, 1, TextureUsage.None,
SurfaceFormat.Color);// create the rectangle texture, ,but it will have no color! lets fix that
Color[] color = new Color[width * height];//set the color to the amount of pixels in the textures

for (int i = 0; i < color.Length; i++)//loop through all the colors setting them to whatever values we want
{
color[i] = new Color(0, 0, 0,255);
}
rectangleTexture.SetData(color);//set the color data on the texture
return rectangleTexture;//return the texture
}

Now go to your LoadContent Method if you don’t know what that is then look for this line of code

protected override void LoadContent()

so inside that method( or inside the { and } ) add the following

myTexture = CreateRectangle(640, 480);//give it a width of 640 and a height of 480

And there we go, now when the the Game loads the Content it will create our lovely filled rectangle. Simple right?
Now to make sure the texture is in fact there you will have to draw it so lets go down to our Draw method( or protected override void Draw(GameTime gameTime) ) and below GraphicsDevice.Clear(Color.CornflowerBlue); add the following

spriteBatch.Begin();
spriteBatch.Draw(myTexture, Vector2.Zero, Color.White);
spriteBatch.End();

now run the game and you should see something like this

the final code is of course below

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 DrawRectangle
{
///
/// This is the main type for your game
///
public class Game1 : Microsoft.Xna.Framework.Game
{
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;

Texture2D rectangle;
public Game1()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = “Content”;
}

public Texture2D CreateRectangle(int width, int height)
{
Texture2D rectangleTexture = new Texture2D(GraphicsDevice, width, height, 1, TextureUsage.None,
SurfaceFormat.Color);// create the rectangle texture, ,but it will have no color! lets fix that
Color[] color = new Color[width * height];//set the color to the amount of pixels

for (int i = 0; i < color.Length; i++)//loop through all the colors setting them to whatever values we want
{
color[i] = new Color(0, 0, 0,255);
}
rectangleTexture.SetData(color);//set the color data on the texture
return rectangleTexture;
}

///
/// 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.
///
protected override void Initialize()
{
// TODO: Add your initialization logic here

base.Initialize();
}

///
/// LoadContent will be called once per game and is the place to load
/// all of your content.
///
protected override void LoadContent()
{
// Create a new SpriteBatch, which can be used to draw textures.
spriteBatch = new SpriteBatch(GraphicsDevice);
rectangle = CreateRectangle(640, 480);
// TODO: use this.Content to load your game content here
}

///
/// UnloadContent will be called once per game and is the place to unload
/// all content.
///
protected override void UnloadContent()
{
// TODO: Unload any non ContentManager content here
}

///
/// Allows the game to run logic such as updating the world,
/// checking for collisions, gathering input, and playing audio.
///
///
Provides a snapshot of timing values. 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

base.Update(gameTime);
}

///
/// This is called when the game should draw itself.
///
///
Provides a snapshot of timing values. protected override void Draw(GameTime gameTime)
{
GraphicsDevice.Clear(Color.CornflowerBlue);

spriteBatch.Begin();
spriteBatch.Draw(rectangle, Vector2.Zero, Color.White);
spriteBatch.End();
base.Draw(gameTime);
}
}
}

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