Accommodate the new video core changes.
The new video core changes allow for some window geometry calculation refactoring that simplify the system:
- Removal of helper functions
- Eliminate some discrepancies between the libdecor and xdg-toplevel paths
- No need to short-circuit the video core window size event deduplication check
- Exclusive fullscreen windows will always end up on the correct output, even when fullscreen is initiated from the compositor
- Better handling of cases where the desktop is scaled, but does not expose the viewport protocol
- Return the display bounds for the emulated mode if an exclusive fullscreen window has focus
- Fixed cases where changing display properties during runtime wouldn't update the display mode lists
- General cleanup
The C specification states that passing a size of 0 to functions like memcpy is valid, but even if the size is 0 and the function is essentially a no-op, the result when passing any invalid pointers is considered undefined behavior. Don't rely on undefined behavior when copying the display or mode lists.
The display list can contain self-referential pointers if the current mode pointer points to the desktop mode or a fullscreen mode array element, and reallocating the display or fullscreen mode lists without updating the current mode pointer in these cases can leave them pointing to freed memory or garbage data. Manually copy the list items and update the self-referential pointers if necessary.
When adding a display, traverse the list of added fullscreen modes and ensure the display ID is set to its final, valid value, or the modes added before calling SDL_AddVideoDisplay() will have an invalid display ID.
Rather than iterating over display modes using an index, there is a new function SDL_GetFullscreenDisplayModes() to get the list of available fullscreen modes on a display.
{
SDL_DisplayID display = SDL_GetPrimaryDisplay();
int num_modes = 0;
SDL_DisplayMode **modes = SDL_GetFullscreenDisplayModes(display, &num_modes);
if (modes) {
for (i = 0; i < num_modes; ++i) {
SDL_DisplayMode *mode = modes[i];
SDL_Log("Display %" SDL_PRIu32 " mode %d: %dx%d@%gHz, %d%% scale\n",
display, i, mode->pixel_w, mode->pixel_h, mode->refresh_rate, (int)(mode->display_scale * 100.0f));
}
SDL_free(modes);
}
}
SDL_GetDesktopDisplayMode() and SDL_GetCurrentDisplayMode() return pointers to display modes rather than filling in application memory.
Windows now have an explicit fullscreen mode that is set, using SDL_SetWindowFullscreenMode(). The fullscreen mode for a window can be queried with SDL_GetWindowFullscreenMode(), which returns a pointer to the mode, or NULL if the window will be fullscreen desktop. SDL_SetWindowFullscreen() just takes a boolean value, setting the correct fullscreen state based on the selected mode.
If the window was fully enclosed, GetDisplayForRect() would return the index of the display ID in the array instead of the display ID itself. Return the display ID itself.