C++博客-^^想你-文章分类-计算几何

三维——面旋转

Huicpc217 — Wed, 23 Sep 2009 05:11:00 GMT

#include
#include
using namespace std;
double pi = acos( -1.);

// 平面内旋转 , 只要是面旋转都可以用，顺时针
int r( double &x, double &y, double t){
    double x1 = x * cos( t ) + y * sin( t );
    double y1 = - x * sin( t ) + y * cos( t );
    x = x1 ; y = y1;
}

int main()
{
    int i, j, k;
    double x, y, z;
    double xn, yn, zn;
    double t;
    while ( scanf("%lf%lf%lf",&x,&y,&z) != EOF )
    {
        scanf("%lf%lf%lf",&xn,&yn,&zn);
        scanf("%lf",&t);
        double t1 = atan2( xn, yn );
        r( yn, xn, t1 );
        r( y, x, t1 );
        double t2 = pi *.5 - atan2( zn, yn );
        r( yn, zn, - t2 );
        r( y, z, - t2 );

        r( y, x, t );
        r( y, z, t2 );
        r( y, x, - t1 );
        printf("%.3lf %.3lf %.3lf\n",x,y,z);
    }
}

Huicpc217 2009-09-23 13:11 发表评论

Hoj 11619 Balance 切割多边形

Huicpc217 — Fri, 28 Aug 2009 09:59:00 GMT

    void sovle()
    {
        this->turn_back();
        polygon a, b;
        int i, j, k;
        point tmp;
        p[n] = p[0];
        point p1( 0 , 0 ), p2( 0 , 0 );
        for ( i = 0 ; i < n ; i ++ )
        {
            if ( p[i].y >= 0 )
                a.add( p[i] );
            if ( p[i].y <= 0 )
                b.add( p[i] );
            if( sig( p[i].y * p[i + 1 ].y ) < 0 )
            {
                tmp.x = p[i].x + ( p[i].y /( p[i].y - p[i+1].y ))*( p[i+1].x - p[i].x );
                // 如此可包含 + - 号的问题
                tmp.y = 0;
                a.add( tmp );
                b.add( tmp );
            }
        }
        p1 = a.poly_centroid();
        p2 = b.poly_centroid();

        if ( sig( p1.x - p2.x ) == 0 )
            printf("Balanced.\n");
        else if ( sig ( p1.x - p2.x ) < 0 )
            printf("CE is aft of CLR by %.2lf units.\n",fabs(p1.x-p2.x));
        else
            printf("CE is forward of CLR by %.2lf units.\n",fabs(p1.x-p2.x));
    }
int main()
{
    polygon poly;

    while( poly.read() != EOF )
    {
        poly.sovle();
    }
    return 0;
}

Huicpc217 2009-08-28 17:59 发表评论

计算几何模板

Huicpc217 — Mon, 24 Aug 2009 14:58:00 GMT

摘要: Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->/*二维几何模板，写入了一些常用函数。使用传引用 & 时，最好加上 const为了控制程序，使其具有灵活性，不写 line ... 阅读全文