向量-计算点到直线的距离

	//获取2个向量的叉乘结果，即平行四边形的面积
	double vecAB[3]={7.0,2.0,0.0};
	double vecAC[3]={5.0,-1.0,0.0};
	double vecCross[3];
	UF_VEC3_cross(vecAB,vecAC,vecCross);

	double tolerance;
	UF_MODL_ask_distance_tolerance(&tolerance);

	//得到点到平面的距离
	double distance;
	UF_VEC3_distance_to_plane(vecCross,vecAB,vecCross,tolerance,&distance);

	//得到AB之间的距离
	double pnt1[3]={3,4,0};
	double pnt2[3]={10,6,0};
	double pnt3[3]={8,3,0};
	double distanceLine;
	UF_VEC3_distance(pnt1,pnt2,&distanceLine);

	char msg[256];
	sprintf(msg,"%f",distance/distanceLine);
	uc1601(msg,1);

a1Xb1 = |a1||b1|sin(a) =平行四边形的面积

三角形面积S = AB*H/2

A1xB1/2 = AB*H/2

H = A1xB1/AB