根据三角形三边一内角,计算出显示在视图上的坐标点

    

    CGFloat w = self.frame.size.width;

    CGFloat h = self.frame.size.height;

    int rectangle = w > h ? h : w;  // 画布大小

    double mMultiples = 1.0;  // 缩放比例

//    double a = 60;

//    double b = 71;

//    double c = 70.9721;

//    double B = 65.0242;

    

    float ax;

    float ay;

    float bx;

    float by;

    float cx;

    float cy;

    

    double max = getMax(fabs(a), fabs(b), fabs(c));  // 3个边长中的最大值

    

    mMultiples = max / (rectangle * 3 / 5);

    a = a / mMultiples;

    b = b / mMultiples;

    c = c / mMultiples;

    

    if (B > 90) {

        bx = (float) (rectangle * 4 / 5 - a);

    } else {

        bx = rectangle / 5;

    }

    by = rectangle * 4 / 5;

    cx = (float) (bx + a);

    cy = by = rectangle * 4 / 5;

    

    if (B > 90) {

        ax = (float) (bx - c * cos((180 - B) / 180 * M_PI));

        ay = (float) (by - c * sin((180 - B) / 180 * M_PI));

    } else {

        if (B < 90) {

            ax = (float) (bx + c * cos((B) / 180 * M_PI));

            ay = (float) (by - c * sin((B) / 180 * M_PI));

        } else {

            ax = bx;

            ay = (float) (by - c);

        }

    }

    

    CGPoint sPoints[3];//坐标点

    sPoints[0] = CGPointMake(ax, ay);//坐标1

    sPoints[1] = CGPointMake(bx, by);//坐标2

    sPoints[2] = CGPointMake(cx, cy);//坐标3