how to check a point if it lies inside a rectangle-CodePudding

I have a rectangle Rect (x,y,w,h) and a point P (px, py). x and y are the top left coordinate of the rectangle. w is it's width. h is it's height. px and py are the coordinate of the point P. Does anyone knows the algorithm to check if P lies inside Rect. Surprisingly, I couldn't find any correct answer for my question on the internet. Much appreciate!

CodePudding user response：

The point P(px, py) lies inside the Rectangle with top left pt. coordinates (x,y) and width and height w&h respectively if both the conditions satisfy:

x < px < (x w)
y > py > (y-h)

Hope this helps :)

CodePudding user response：

It's just a metter of checking that x is within the rectangle left and right sides and that y is within top and bottom:

#include <iostream>

struct Point {
    double x, y;
};

struct Rect {
    double x, y, w, h;
    
    bool contains(const Point& p) {
        return p.x >= x && p.y >= y && p.x <= x w && p.y <= y h;
    }
};

int main() {
    Rect r({ 3,4,5,8 });
    std::cout << r.contains({ 3.2, 7.3 });
    return 0;
}

CodePudding user response：

use this piece of code:

#include <iostream>

int main()
{
  int x, y, w, h;
  std::cin >> x >> y >> w >> h;
      
  int px, py;
  std::cin >> px >> py;
  
  if(px >= x && px <= (x   w) && py <= y && py >= (y - h))
    std::cout << "point is in the rectangle";
  else
    std::cout << "point is out of the rectangle";
}