如何使对象在以表单呈现时“可缩放”

我正在 Winform 中渲染我的游戏，方式与本示例中的方式相同：WinForms系列1：图形设备 http://xbox.create.msdn.com/en-US/education/catalog/sample/winforms_series_1

在我的游戏中，我有一些对象，例如一个矩形，一旦创建，我就可以在我的游戏世界中放置和移动它。我的项目是一个关卡编辑器。

What I want to do is to make every object "sizable" or "scalable" (sorry if this isn't the correct word) in the same way as done in every software we commonly use, I mean:

我有一堂课，比如：

public abstract class GameObject
{
    protected Vector2 position_ = Vector2.Zero;
    protected float rotation_ = 0.0f;
    protected Vector2 scale_ = Vector2.One;
    protected float depth_ = 0.0f;

    protected bool is_passable_ = true;

    protected GameObject(
        Vector2 starting_position)
    {
        this.position_ = starting_position;
    }

    [DisplayName("Position")]
    public virtual Vector2 Position
    {
        get { return position_; }
        set { position_ = value; }
    }

    [BrowsableAttribute(false)]
    public abstract Rectangle PositionRectangle
    {
        get;
    }

    [BrowsableAttribute(false)]
    public abstract Rectangle SelectionRectangle
    {
        get;
    }

    [DisplayName("Scale")]
    public abstract Vector2 Scale
    {
        get;
        set;
    }

    [BrowsableAttribute(false)]
    public virtual float Depth
    {
        get { return depth_; }
        set { depth_ = value; }
    }

    [DisplayName("IsPassable?")]
    public bool IsPassable
    {
        get { return is_passable_; }
        set { is_passable_ = value; }
    }

    [BrowsableAttribute(false)]
    public abstract Vector2 TextureSize
    {
        get;
    }

    public abstract void Update(GameTime gameTime);
    public abstract void Draw(SpriteBatch spriteBatch);
}

一旦类被实例化，我想在表单内执行类似的操作：（gameWrapper 是使用示例创建的控件，用于在表单内绘制游戏）

private void gameWrapper_MouseClick_1(object sender, MouseEventArgs e)
{
    Vector2 mouse_xy = new Vector2(e.Location.X, e.Location.Y);
    GameObject obj = gameWrapper.GetObjectByPosition(mouse_xy);
    propertyGrid1.SelectedObject = obj;
    if (obj != null)
        gameWrapper.SelectObject(obj);
    else gameWrapper.Unselect();

    propertyGrid1.Refresh();
 }

游戏包装内部：

public SelectObject(GameObject obj)
{
     List<Vector2> 4verticesList = new List();
     //
     // Code to add 4 vertices coordinates of the SelectionRectangle to 4verticesList
     //         

     foreach (Vector2 vertex_xy in 4VerticesList)
        DrawLittleRectangle(vertex_xy);
}

这正是我想做的。使用函数绘制小按钮/矩形，然后处理对它们的点击。

是否已经编写了一些代码来实现此行为？实际上，我并不担心对象将如何调整大小，而只是担心美观按钮。

我已经做到了！

主要功能：

private void DrawObjectSelection(SpriteBatch spriteBatch, Rectangle r)
{
    r = Telecamera.Transform(r);

    Vector2 v1 = new Vector2(r.X, r.Y);
    Vector2 v2 = new Vector2(r.X + r.Width, r.Y);
    Vector2 v3 = new Vector2(r.X, r.Y + r.Height);
    Vector2 v4 = new Vector2(r.X + r.Width, r.Y + r.Height);

    //The side rectangle
    DrawEmptyRectangle(spriteBatch, v1, v2, v3, v4);

    //4 squares at vertices
    DrawFilledSquare(spriteBatch, v1);
    DrawFilledSquare(spriteBatch, v2);
    DrawFilledSquare(spriteBatch, v3);
    DrawFilledSquare(spriteBatch, v4);

    //the other 4 in the middle of every side
    float height = v4.Y - v1.Y;
    float width = v2.X - v1.X;

    DrawFilledSquare(spriteBatch, new Vector2(v1.X, v1.Y + height / 2));
    DrawFilledSquare(spriteBatch, new Vector2(v2.X, v2.Y + height / 2));
    DrawFilledSquare(spriteBatch, new Vector2(v1.X + width / 2, v1.Y));
    DrawFilledSquare(spriteBatch, new Vector2(v1.X + width / 2, v4.Y));
}

具有这些功能：

private void DrawLine(
    SpriteBatch spriteBatch,
    float width,
    Vector2 point1, Vector2 point2)
{
    float angle = (float)Math.Atan2(point2.Y - point1.Y, point2.X - point1.X);
    float length = Vector2.Distance(point1, point2);

    spriteBatch.Draw(
        grid_texture,
        point1,
        null,
        selection_color,
        angle,
        Vector2.Zero,
        new Vector2(length, width),
        SpriteEffects.None,
        0);
}

private void DrawEmptyRectangle(
    SpriteBatch spriteBatch,
    Vector2 v1,
    Vector2 v2,
    Vector2 v3,
    Vector2 v4)
{
    /*
     * V1****V2
     * *      *
     * *      *
     * V3****V4
     */

    DrawLine(spriteBatch, 1.0f, v1, v2);
    DrawLine(spriteBatch, 1.0f, v1, v3);
    DrawLine(spriteBatch, 1.0f, v2, v4);
    DrawLine(spriteBatch, 1.0f, v3, v4);
}

private void DrawFilledSquare(
    SpriteBatch spriteBatch,
    Vector2 c_pos) //With center position
{
    int lato = 8;

    spriteBatch.Draw(
        grid_texture,
        new Rectangle(
            (int)c_pos.X - lato/2,
            (int)c_pos.Y - lato/2,
            lato,
            lato),
            selection_color);

}

当我想绘制它时，我只需要一个矩形，例如：

//...

DrawObjectSelection(spriteBatch, Camera.Transform(gameObject1.PositionRectangle));

//...

唯一缺少的是处理每个方块上的点击。这是通过使用鼠标位置坐标进行简单的“包含”测试来完成的。

结果屏幕：