The SDL_GetWindowBordersSize() function returns the size of a window’s decorations.
However, when called on a borderless window, the function typically sets all decoration size values (top, left, bottom, right) to 0. This is because a borderless window has no decorations to measure.
Here’s an example demonstrating this:
#include <SDL.h>
#include <iostream>
int main() {
SDL_Init(SDL_INIT_VIDEO);
SDL_Window* Borderless{SDL_CreateWindow(
"Borderless",
100, 100, 300, 200,
SDL_WINDOW_BORDERLESS
)};
int Top, Left, Bottom, Right;
if (SDL_GetWindowBordersSize(
Borderless, &Top, &Left, &Bottom, &Right
) == 0) {
std::cout << "Top: " << Top
<< ", Left: " << Left
<< ", Bottom: " << Bottom
<< ", Right: " << Right << "\n";
} else {
std::cout << "Error: "
<< SDL_GetError() << "\n";
}
SDL_DestroyWindow(Borderless);
SDL_Quit();
}Top: 0, Left: 0, Bottom: 0, Right: 0This behavior is consistent across platforms where SDL abstracts the windowing system. Note that using SDL_GetWindowBordersSize() on a borderless window will never result in an error unless the window pointer itself is invalid.
Answers to questions are automatically generated and may not have been reviewed.
This Question is from the Lesson:
Window Decorations and Borders
An introduction to managing SDL2 window decorations, borders, and client areas.
