Function bloom_init_window

native/macos/src/lib.rs:251–462

(width: f64, height: f64, title_ptr: *const u8, fullscreen: f64)

#[no_mangle]
pub extern "C" fn bloom_init_window(width: f64, height: f64, title_ptr: *const u8, fullscreen: f64) {
    let title = str_from_header(title_ptr);
    let mtm = MainThreadMarker::from(unsafe { MainThreadMarker::new_unchecked() });

    // Headless mode: BLOOM_HEADLESS=1 keeps the NSWindow + CAMetalLayer
    // alive (wgpu's Metal backend requires a CAMetalLayer-backed view)
    // but hides the window and suppresses dock icon / focus. Needed
    // so an agent can spin up the renderer in a batch loop without
    // stealing the user's focus on every sample.
    let headless = std::env::var("BLOOM_HEADLESS")
        .map(|v| v == "1" || v.eq_ignore_ascii_case("true"))
        .unwrap_or(false);
    unsafe { HEADLESS = headless; }

    let app = NSApplication::sharedApplication(mtm);
    if headless {
        // Prohibited = no dock icon, no menu bar, no activation.
        app.setActivationPolicy(NSApplicationActivationPolicy::Prohibited);
    } else {
        app.setActivationPolicy(NSApplicationActivationPolicy::Regular);
    }

    // Far-off-screen origin keeps the window out of every display
    // even if the OS insists on showing something.
    let origin_x = if headless { -20000.0 } else { 100.0 };
    let content_rect = NSRect::new(NSPoint::new(origin_x, 100.0), NSSize::new(width, height));
    let style = NSWindowStyleMask::Titled
        | NSWindowStyleMask::Closable
        | NSWindowStyleMask::Miniaturizable
        | NSWindowStyleMask::Resizable;

    let window = unsafe {
        NSWindow::initWithContentRect_styleMask_backing_defer(
            NSWindow::alloc(mtm),
            content_rect,
            style,
            objc2_app_kit::NSBackingStoreType(2), // NSBackingStoreBuffered
            false,
        )
    };

    let ns_title = NSString::from_str(title);
    window.setTitle(&ns_title);

    // Don't persist window size/fullscreen state across launches.
    // NSWindow restoration was resurrecting a prior fullscreen toggle on
    // the 4K display, which silently rendered benchmarks at 4× the
    // requested pixel count.
    unsafe { let _: () = msg_send![&window, setRestorable: false]; }

    // BLOOM_NO_FULLSCREEN=1 hard-disables fullscreen capability: the
    // window cannot be entered into fullscreen via the green button,
    // cmd-ctrl-F, or inheriting a fullscreen Space from the launching
    // terminal. Intended for benchmark harnesses where the 4K-display
    // fullscreen path would otherwise silently quadruple render cost.
    let no_fullscreen = std::env::var("BLOOM_NO_FULLSCREEN")
        .map(|v| v == "1" || v.eq_ignore_ascii_case("true"))
        .unwrap_or(false);