我有一个关于 C# 游戏编程中精灵碰撞的 C# 片段代码,希望你们能帮助我澄清它。
我不明白 IsCollided 方法,尤其是计算 d1 和 d2 以确定精灵是否碰撞,在这种情况下 Matrix Invert() 和 Multiphy 的含义和使用以及使用 Color alpha 分量来确定碰撞2 个精灵。
非常感谢你。
public struct Vector
{
public double X;
public double Y;
public Vector(double x, double y)
{
X = x;
Y = y;
}
public static Vector operator -(Vector v, Vector v2)
{
return new Vector(v.X-v2.X, v.Y-v2.Y);
}
public double Length
{
get
{
return Math.Sqrt(X * X + Y * Y);
}
}
}
public class Sprite
{
public Vector Position;
protected Image _Image;
protected Bitmap _Bitmap;
protected string _ImageFileName = "";
public string ImageFileName
{
get { return _ImageFileName; }
set
{
_ImageFileName = value;
_Image = Image.FromFile(value);
_Bitmap = new Bitmap(value);
}
}
public Matrix Transform
{
get
{
Vector v = Position;
if (null != _Image)
v -= new Vector(_Image.Size) / 2;
Matrix m = new Matrix();
m.RotateAt(50.0F, new PointF(10.0F, 100.0F));
m.Translate((float)v.X, (float)v.Y);
return m;
}
}
public bool IsCollided(Sprite s2)
{
Vector v = this.Position - s2.Position;
double d1 = Math.Sqrt(_Image.Width * _Image.Width + _Image.Height * _Image.Height)/2;
double d2 = Math.Sqrt(s2._Image.Width * s2._Image.Width + s2._Image.Height * s2._Image.Height)/2;
if (v.Length > d1 + d2)
return false;
Bitmap b = new Bitmap(_Image.Width, _Image.Height);
Graphics g = Graphics.FromImage(b);
Matrix m = s2.Transform;
Matrix m2 = Transform;
m2.Invert();
Matrix m3 = m2;
m3.Multiply(m);
g.Transform = m3;
Vector2F v2 = new Vector2F(0,0);
g.DrawImage(s2._Image, v2);
for (int x = 0; x < b.Width; ++x)
for (int y = 0; y < b.Height; ++y)
{
Color c1 = _Bitmap.GetPixel(x, y);
Color c2 = b.GetPixel(x, y);
if (c1.A > 0.5 && c2.A > 0.5)
return true;
}
return false;
}
}