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644

answers:

2

Hey guys, I was working on game, and wanted to highlight a spot on the screen when something happens, I created a class to do this for me, and found a bit of code to draw the rectangle

static private Texture2D CreateRectangle(int width, int height, Color colori)
{
    Texture2D rectangleTexture = new Texture2D(game.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] = colori;
    }
    rectangleTexture.SetData(color);//set the color data on the texture
    return rectangleTexture;//return the texture
}

Problem is that the code above is called every update, (60 times a second), and it was not written with optimization in mind, I have no clue how else to write a code to do this though. It needs to be extremely fast (the code above freezes the game, which has only skeleton code right now).. Any suggestions. Note: Any new code would be great (WireFrame/Fill are both fine). I would like to be able to specify color.

Something to point in the right direction would be great, Thanks, Max

A: 

This is probably not the best solution, but you should be able to use a 1x1 pixel texture stretched to fit the rectangle.

Foole
+4  A: 

The SafeArea demo on the XNA Creators Club site has code to do specifically that.

You don't have to create the Texture every frame, just in LoadContent. A very stripped down version of the code from that demo:

public class RectangleOverlay : DrawableGameComponent
{
    SpriteBatch spriteBatch;
    Texture2D dummyTexture;
    Rectangle dummyRectangle;
    Color Colori;

    public RectangleOverlay(Rectangle rect, Color colori, Game game)
        : base(game)
    {
        // Choose a high number, so we will draw on top of other components.
        DrawOrder = 1000;
        dummyRectangle = rect;
        Colori = colori;
    }

    protected override void LoadContent()
    {
        spriteBatch = new SpriteBatch(GraphicsDevice);
        dummyTexture = new Texture2D(GraphicsDevice, 1, 1);
        dummyTexture.SetData(new Color[] { Color.White });
    }

    public override void Draw(GameTime gameTime)
    {
        spriteBatch.Begin();
        spriteBatch.Draw(dummyTexture, dummyRectangle, Colori);
        spriteBatch.End();
    }
}
Bob
Thanks! works like a charm.
mazzzzz