C++ Wrong margin of the rackets in a window

Question

int width = 800;
int height = 600;
int interval = 1000 / 60;
int score_player1 = 0;
int score_player2 = 0;
int racket_width = 10;
int racket_height = 80;
int racket_speed = 8;
int racket_left_x = 10;
int racket_left_y = 50;
int racket_right_x = width - racket_width - 10;
int racket_right_y = 50;

Full code (without the class for the ball): http://pastebin.com/TA9NkV5c

The margin from the right racket to right side of the window is smaller than the left side. The variables for those are right calculated, but still, it is not equally.

https://i.stack.imgur.com/OjqtZ.png Link to the image

Answer 1

You've set the window to a width of 800 pixels, but everything else is positioned relative to the client region, which is narrower than the window width by the thickness of the border.

Use AdjustWindowRect to compute the size you have to make the window in order get the client area to be the desired size.

// Initialize a RECT with the size you want the client area to be.
RECT rc = { 0, 0, width, height };
// Now adjust the rectangle to the size the window would need to be.
AdjustWindowRect(&rc, my_style_flags, FALSE);

// Now create the window using the sizes in rc.  Make sure you use
// consistent style flags or the adjustment may not be correct.
const int window_width = rc.right - rc.left;
const int window_height = rc.bottom - rc.top;
my_hwnd = CreateWindow(..., my_style_flags, x, y, window_width, window_height, ...);