[代码技巧]

1.限定范围[0,255]

            int iValue = int(dValue);
            iValue = MIN(255, iValue);
            iValue = MAX(0, iValue);

2.四舍五入一句话就搞定

float tmp=8.8;
int val=tmp+0.5;

3. 一句话转奇数

int a=b/2*2+1;//b's type is int