通常情况下,你会为游戏中的游标指定一个纹理,例如[16,16]处的像素就是你瞄准的地方(比如十字线的中心)。你以鼠标为中心绘制这个图像的方法是使用Mouse.GetState()来获取位置,然后用“目标”点的“中心”的负值偏移鼠标纹理的图形。
让我们说,我们创建一个自定义鼠标类别:
public class GameMouse
{
public Vector2 Position = Vector2.Zero;
private Texture2D Texture { get; set; }
private Vector2 CenterPoint = Vector2.Zero;
public MouseState State { get; set; }
public MouseState PreviousState { get; set; }
//Returns true if left button is pressed (true as long as you hold button)
public Boolean LeftDown
{
get { return State.LeftButton == ButtonState.Pressed; }
}
//Returns true if left button has been pressed since last update (only once per click)
public Boolean LeftPressed
{
get { return (State.LeftButton == ButtonState.Pressed) &&
(PreviousState.LeftButton == ButtonState.Released); }
}
//Initialize texture and states.
public GameMouse(Texture2D texture, Vector2 centerPoint)
{
Texture = texture;
CenterPoint = centerPoint;
State = Mouse.GetState();
//Calling Update will set previousstate and update Position.
Update();
}
public void Update()
{
PreviousState = State;
State = Mouse.GetState();
Position.X = State.X;
Position.Y = State.Y;
}
public void Draw(SpriteBatch spriteBatch)
{
spriteBatch.Begin();
spriteBatch.Draw(Texture, Position - CenterPoint, Color.White);
spriteBatch.End();
}
}