使用XNA绘制矩形

我正在做游戏。 当有事情发生时，我想在屏幕上突出显示一个位置。

我为我创建了一个类，并找到了一些绘制矩形的代码：

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 } 

问题是上面的代码在每次更新时调用（每秒60次），并且没有考虑优化。 它需要非常快（上面的代码冻结游戏，现在只有骨架代码）。

有什么建议？

注意：任何新代码都会很棒（WireFrame / Fill都很好）。 我希望能够指定颜色。

Answer 1

XNA Creators Club网站上的SafeArea演示具有专门的代码。

您不必每一帧都创建纹理，只需在LoadContent 。 该演示代码的一个非常精简的版本：

 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(); } } 

Answer 2

这就是我做到的。 它可能不是最快或最好的解决方案，但它确实有效。

 using System; using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Graphics; namespace Engine { /// 
 /// An extended version of the SpriteBatch class that supports line and /// rectangle drawing. /// 
 public class ExtendedSpriteBatch : SpriteBatch { /// 
 /// The texture used when drawing rectangles, lines and other /// primitives. This is a 1x1 white texture created at runtime. /// 
 public Texture2D WhiteTexture { get; protected set; } public ExtendedSpriteBatch(GraphicsDevice graphicsDevice) : base(graphicsDevice) { this.WhiteTexture = new Texture2D(this.GraphicsDevice, 1, 1); this.WhiteTexture.SetData(new Color[] { Color.White }); } /// 
 /// Draw a line between the two supplied points. /// 
 /// Starting point. /// End point. /// The draw color. public void DrawLine(Vector2 start, Vector2 end, Color color) { float length = (end - start).Length(); float rotation = (float)Math.Atan2(end.Y - start.Y, end.X - start.X); this.Draw(this.WhiteTexture, start, null, color, rotation, Vector2.Zero, new Vector2(length, 1), SpriteEffects.None, 0); } /// 
 /// Draw a rectangle. /// 
 /// The rectangle to draw. /// The draw color. public void DrawRectangle(Rectangle rectangle, Color color) { this.Draw(this.WhiteTexture, new Rectangle(rectangle.Left, rectangle.Top, rectangle.Width, 1), color); this.Draw(this.WhiteTexture, new Rectangle(rectangle.Left, rectangle.Bottom, rectangle.Width, 1), color); this.Draw(this.WhiteTexture, new Rectangle(rectangle.Left, rectangle.Top, 1, rectangle.Height), color); this.Draw(this.WhiteTexture, new Rectangle(rectangle.Right, rectangle.Top, 1, rectangle.Height + 1), color); } /// 
 /// Fill a rectangle. /// 
 /// The rectangle to fill. /// The fill color. public void FillRectangle(Rectangle rectangle, Color color) { this.Draw(this.WhiteTexture, rectangle, color); } } } 

Answer 3

这可能不是最好的解决方案，但您应该能够使用拉伸的1×1像素纹理来适应矩形。