射击的乐趣：WIN32诠释打飞机游戏源码补充

 1 void CbitmapDlg::OnHit()
 2 {
 3     //defender hit
 4     for(int i = 0; i < iCurplane; i++)
 5     {
 6         //修正定时器偏差和键盘消息之间偏差导致的错误碰撞检测
 7         if (plane[i].status == DESTROYED)
 8             continue;
 9         int defendcox = superdefender.pos_x + superdefender.Deswidth/2;
10         int defendcoy = superdefender.pos_y + superdefender.Desheight/2;
11         int planecox = plane[i].pos_x + plane[i].Deswidth/2;
12         int planecoy = plane[i].pos_y + plane[i].Desheight/2;
13 
14         //按照圆形包围体检测
15         if(((defendcox - planecox)*(defendcox - planecox) + (defendcoy - planecoy)*(defendcoy - planecoy)) > ((superdefender.Desheight + plane[i].Desheight)*(superdefender.Desheight + plane[i].Desheight)/4 + (superdefender.Deswidth + plane[i].Deswidth)*(superdefender.Deswidth + plane[i].Deswidth)/4))
16             continue;
17         else
18         {
19             //检测defender的4个点是否碰撞到飞机
20             CRect rect;
21             rect.left = plane[i].pos_x;
22             rect.right = plane[i].pos_x + plane[i].Deswidth;
23             rect.top = plane[i].pos_y;
24             rect.bottom = plane[i].pos_y + plane[i].Desheight;
25 
26             CPoint point1, point2, point3, point4;
27             point1.x = superdefender.pos_x;
28             point1.y = superdefender.pos_y;
29             point2.x = superdefender.pos_x + superdefender.Deswidth;
30             point2.y = superdefender.pos_y;
31             point3.x = superdefender.pos_x;
32             point3.y = superdefender.pos_y + superdefender.Desheight;
33             point4.x = superdefender.pos_x + superdefender.Deswidth;
34             point4.y = superdefender.pos_y + superdefender.Desheight;
35 
36             if(PtInRect(rect, point1) || PtInRect(rect, point2) || PtInRect(rect, point3) || PtInRect(rect, point4))
37                 superdefender.status = DESTROYED;
38 
39         }
40         if(superdefender.status == DESTROYED)
41         {
42             life -= 1;
43             AddDefender();
44             return ;
45         }
46     }
47 }