问题描述
矩形坐标:
矩形1:x:180 y:30
矩形2:x:160 y:30
我注意到的是,渲染从一个点开始,并在X轴上按宽度增加,在Y轴上按高度增加。所以我推导出以下内容:x1和y1等于矩形坐标(x1和y1是左上角),x2,y2是右下角/坐标,它们等于正方形坐标之和或x1和y1以及正方形的宽度和高度。
那是我编写的代码:
#include <stdio.h>
#include <iostream>
struct A
{
int x1,x2;
int y1,y2;
};
struct B
{
int x1,y2;
};
bool doOverlap(A a,B b)
{
if (a.x1 < b.x2 && a.x2 > b.x1 &&
a.y1 > b.y2 && a.y2 < b.y1)
return true;
return false;
}
int main()
{
/*
Rectangle 1 coords: X: 180 Y: 30
Rectangle 2 coords: X: 160 Y: 30
*/
A a;
B b;
/*
The render begins from top left corner (that's our center and
from here begins the render with +width on x and +heigth on y
(correct me in case i'm wrong but that's what i noticed: https://imgur.com/a/nZKBB0m
(as can you see in that photo,the white rectangle has l1: (x,y): 0 0)
rectangles are 40x40
*/
a.x1 = 180;
a.y1 = 30;
a.x2 = a.x1 + 40;
a.y2 = a.y1 + 40;
b.x1 = 160;
b.y1 = 30;
b.x2 = b.x1 + 40;
b.y2 = b.y1 + 40;
if (doOverlap(a,b))
{
std::cout << "y";
}
else
std::cout << "n";
return 0;
}
问题是它总是返回false(检查了很多代码,但是似乎没有一个在工作) 那么,我该怎么办?
解决方法
您仅检查a是否高于b,然后检查a是否离开b。 您需要检查a和b的x间隔是否重叠,然后检查y间隔是否重叠。这是一种方法:
bool doOverlap(A a,B b)
{
if (a.x1 > b.x2 || b.x1 > a.x2)
return false;
if (a.y1 > b.y2 || b.y1 > a.y2)
return false;
return true;
}
第一个if检查a和b的x间隔是否重叠,如果不重叠则返回false。第二个在y间隔中相同。如果x和y间隔都重叠,则矩形重叠