c语言基础问题
double now = now_ms(); double renderTime = now - s->frameTime; double frameTime = now - s->lastTime;
double now = now_ms(); /* now是double型变量,初始值是now_ms()函数的返回值 */ double renderTime = now - (s->frameTime);/* 加个括号应该能看明白了吧?now减去结构体s中的成员变量frameTime的值 */ double frameTime = now - (s->lastTime);