use crate::{
DevicePixels, ForegroundExecutor, SharedString, SourceMetadata,
platform::{ScreenCaptureFrame, ScreenCaptureSource, ScreenCaptureStream},
size,
};
use anyhow::{Result, anyhow};
use block::ConcreteBlock;
use cocoa::{
base::{YES, id, nil},
foundation::{NSArray, NSString},
};
use collections::HashMap;
use core_foundation::base::TCFType;
use core_graphics::display::{
CGDirectDisplayID, CGDisplayBounds, CGDisplayCopyDisplayMode, CGDisplayModeGetPixelHeight,
CGDisplayModeGetPixelWidth, CGDisplayModeRelease, CGGetActiveDisplayList,
};
use ctor::ctor;
use futures::channel::oneshot;
use media::core_media::{CMSampleBuffer, CMSampleBufferRef};
use metal::NSInteger;
use objc::{
class,
declare::ClassDecl,
msg_send,
runtime::{Class, Object, Sel},
sel, sel_impl,
};
use std::{cell::RefCell, ffi::c_void, mem, ptr, rc::Rc};
use super::NSStringExt;
#[derive(Clone)]
pub struct MacScreenCaptureSource {
sc_display: id,
meta: Option<ScreenMeta>,
}
pub struct MacScreenCaptureStream {
sc_stream: id,
sc_stream_output: id,
meta: SourceMetadata,
}
static mut DELEGATE_CLASS: *const Class = ptr::null();
static mut OUTPUT_CLASS: *const Class = ptr::null();
const FRAME_CALLBACK_IVAR: &str = "frame_callback";
#[allow(non_upper_case_globals)]
const SCStreamOutputTypeScreen: NSInteger = 0;
impl ScreenCaptureSource for MacScreenCaptureSource {
fn metadata(&self) -> Result<SourceMetadata> {
let (display_id, size) = unsafe {
let display_id: CGDirectDisplayID = msg_send![self.sc_display, displayID];
let display_mode_ref = CGDisplayCopyDisplayMode(display_id);
let width = CGDisplayModeGetPixelWidth(display_mode_ref);
let height = CGDisplayModeGetPixelHeight(display_mode_ref);
CGDisplayModeRelease(display_mode_ref);
(
display_id,
size(DevicePixels(width as i32), DevicePixels(height as i32)),
)
};
let (label, is_main) = self
.meta
.clone()
.map(|meta| (meta.label, meta.is_main))
.unzip();
Ok(SourceMetadata {
id: display_id as u64,
label,
is_main,
resolution: size,
})
}
fn stream(
&self,
_foreground_executor: &ForegroundExecutor,
frame_callback: Box<dyn Fn(ScreenCaptureFrame) + Send>,
) -> oneshot::Receiver<Result<Box<dyn ScreenCaptureStream>>> {
unsafe {
let stream: id = msg_send![class!(SCStream), alloc];
let filter: id = msg_send![class!(SCContentFilter), alloc];
let configuration: id = msg_send![class!(SCStreamConfiguration), alloc];
let delegate: id = msg_send![DELEGATE_CLASS, alloc];
let output: id = msg_send![OUTPUT_CLASS, alloc];
let excluded_windows = NSArray::array(nil);
let filter: id = msg_send![filter, initWithDisplay:self.sc_display excludingWindows:excluded_windows];
let configuration: id = msg_send![configuration, init];
let _: id = msg_send![configuration, setScalesToFit: true];
let _: id = msg_send![configuration, setPixelFormat: 0x42475241];
let delegate: id = msg_send![delegate, init];
let output: id = msg_send![output, init];
output.as_mut().unwrap().set_ivar(
FRAME_CALLBACK_IVAR,
Box::into_raw(Box::new(frame_callback)) as *mut c_void,
);
let meta = self.metadata().unwrap();
let _: id = msg_send![configuration, setWidth: meta.resolution.width.0 as i64];
let _: id = msg_send![configuration, setHeight: meta.resolution.height.0 as i64];
let stream: id = msg_send![stream, initWithFilter:filter configuration:configuration delegate:delegate];
let (mut tx, rx) = oneshot::channel();
let mut error: id = nil;
let _: () = msg_send![stream, addStreamOutput:output type:SCStreamOutputTypeScreen sampleHandlerQueue:0 error:&mut error as *mut id];
if error != nil {
let message: id = msg_send![error, localizedDescription];
tx.send(Err(anyhow!("failed to add stream output {message:?}")))
.ok();
return rx;
}
let tx = Rc::new(RefCell::new(Some(tx)));
let handler = ConcreteBlock::new({
move |error: id| {
let result = if error == nil {
let stream = MacScreenCaptureStream {
meta: meta.clone(),
sc_stream: stream,
sc_stream_output: output,
};
Ok(Box::new(stream) as Box<dyn ScreenCaptureStream>)
} else {
let message: id = msg_send![error, localizedDescription];
Err(anyhow!("failed to stop screen capture stream {message:?}"))
};
if let Some(tx) = tx.borrow_mut().take() {
tx.send(result).ok();
}
}
});
let handler = handler.copy();
let _: () = msg_send![stream, startCaptureWithCompletionHandler:handler];
rx
}
}
}
impl Drop for MacScreenCaptureSource {
fn drop(&mut self) {
unsafe {
let _: () = msg_send![self.sc_display, release];
}
}
}
impl ScreenCaptureStream for MacScreenCaptureStream {
fn metadata(&self) -> Result<SourceMetadata> {
Ok(self.meta.clone())
}
}
impl Drop for MacScreenCaptureStream {
fn drop(&mut self) {
unsafe {
let mut error: id = nil;
let _: () = msg_send![self.sc_stream, removeStreamOutput:self.sc_stream_output type:SCStreamOutputTypeScreen error:&mut error as *mut _];
if error != nil {
let message: id = msg_send![error, localizedDescription];
log::error!("failed to add stream output {message:?}");
}
let handler = ConcreteBlock::new(move |error: id| {
if error != nil {
let message: id = msg_send![error, localizedDescription];
log::error!("failed to stop screen capture stream {message:?}");
}
});
let block = handler.copy();
let _: () = msg_send![self.sc_stream, stopCaptureWithCompletionHandler:block];
let _: () = msg_send![self.sc_stream, release];
let _: () = msg_send![self.sc_stream_output, release];
}
}
}
#[derive(Clone)]
struct ScreenMeta {
label: SharedString,
is_main: bool,
}
unsafe fn screen_id_to_human_label() -> HashMap<CGDirectDisplayID, ScreenMeta> {
let screens: id = msg_send![class!(NSScreen), screens];
let count: usize = msg_send![screens, count];
let mut map = HashMap::default();
let screen_number_key = unsafe { NSString::alloc(nil).init_str("NSScreenNumber") };
for i in 0..count {
let screen: id = msg_send![screens, objectAtIndex: i];
let device_desc: id = msg_send![screen, deviceDescription];
if device_desc == nil {
continue;
}
let nsnumber: id = msg_send![device_desc, objectForKey: screen_number_key];
if nsnumber == nil {
continue;
}
let screen_id: u32 = msg_send![nsnumber, unsignedIntValue];
let name: id = msg_send![screen, localizedName];
if name != nil {
let cstr: *const std::os::raw::c_char = msg_send![name, UTF8String];
let rust_str = unsafe {
std::ffi::CStr::from_ptr(cstr)
.to_string_lossy()
.into_owned()
};
map.insert(
screen_id,
ScreenMeta {
label: rust_str.into(),
is_main: i == 0,
},
);
}
}
map
}
pub(crate) fn get_sources() -> oneshot::Receiver<Result<Vec<Rc<dyn ScreenCaptureSource>>>> {
unsafe {
let (mut tx, rx) = oneshot::channel();
let tx = Rc::new(RefCell::new(Some(tx)));
let screen_id_to_label = screen_id_to_human_label();
let block = ConcreteBlock::new(move |shareable_content: id, error: id| {
let Some(mut tx) = tx.borrow_mut().take() else {
return;
};
let result = if error == nil {
let displays: id = msg_send![shareable_content, displays];
let mut result = Vec::new();
for i in 0..displays.count() {
let display = displays.objectAtIndex(i);
let id: CGDirectDisplayID = msg_send![display, displayID];
let meta = screen_id_to_label.get(&id).cloned();
let source = MacScreenCaptureSource {
sc_display: msg_send![display, retain],
meta,
};
result.push(Rc::new(source) as Rc<dyn ScreenCaptureSource>);
}
Ok(result)
} else {
let msg: id = msg_send![error, localizedDescription];
Err(anyhow!(
"Screen share failed: {:?}",
NSStringExt::to_str(&msg)
))
};
tx.send(result).ok();
});
let block = block.copy();
let _: () = msg_send![
class!(SCShareableContent),
getShareableContentExcludingDesktopWindows:YES
onScreenWindowsOnly:YES
completionHandler:block];
rx
}
}
#[ctor]
unsafe fn build_classes() {
let mut decl = ClassDecl::new("GPUIStreamDelegate", class!(NSObject)).unwrap();
unsafe {
decl.add_method(
sel!(outputVideoEffectDidStartForStream:),
output_video_effect_did_start_for_stream as extern "C" fn(&Object, Sel, id),
);
decl.add_method(
sel!(outputVideoEffectDidStopForStream:),
output_video_effect_did_stop_for_stream as extern "C" fn(&Object, Sel, id),
);
decl.add_method(
sel!(stream:didStopWithError:),
stream_did_stop_with_error as extern "C" fn(&Object, Sel, id, id),
);
DELEGATE_CLASS = decl.register();
let mut decl = ClassDecl::new("GPUIStreamOutput", class!(NSObject)).unwrap();
decl.add_method(
sel!(stream:didOutputSampleBuffer:ofType:),
stream_did_output_sample_buffer_of_type
as extern "C" fn(&Object, Sel, id, id, NSInteger),
);
decl.add_ivar::<*mut c_void>(FRAME_CALLBACK_IVAR);
OUTPUT_CLASS = decl.register();
}
}
extern "C" fn output_video_effect_did_start_for_stream(_this: &Object, _: Sel, _stream: id) {}
extern "C" fn output_video_effect_did_stop_for_stream(_this: &Object, _: Sel, _stream: id) {}
extern "C" fn stream_did_stop_with_error(_this: &Object, _: Sel, _stream: id, _error: id) {}
extern "C" fn stream_did_output_sample_buffer_of_type(
this: &Object,
_: Sel,
_stream: id,
sample_buffer: id,
buffer_type: NSInteger,
) {
if buffer_type != SCStreamOutputTypeScreen {
return;
}
unsafe {
let sample_buffer = sample_buffer as CMSampleBufferRef;
let sample_buffer = CMSampleBuffer::wrap_under_get_rule(sample_buffer);
if let Some(buffer) = sample_buffer.image_buffer() {
let callback: Box<Box<dyn Fn(ScreenCaptureFrame)>> =
Box::from_raw(*this.get_ivar::<*mut c_void>(FRAME_CALLBACK_IVAR) as *mut _);
callback(ScreenCaptureFrame(buffer));
mem::forget(callback);
}
}
}
use crate::media_capture::{
CaptureBackend, CaptureConfig, CaptureDeviceInfo, CaptureDeviceKind, CaptureSession,
CaptureSessionState, DeviceEnumerator, FrameCallback,
};
use std::sync::atomic::{AtomicU64, Ordering};
pub struct MacScreenCaptureBackend;
impl MacScreenCaptureBackend {
pub fn new() -> Self {
Self
}
}
impl DeviceEnumerator for MacScreenCaptureBackend {
fn devices(&self, kind: CaptureDeviceKind) -> Result<Vec<CaptureDeviceInfo>> {
match kind {
CaptureDeviceKind::Screen => {
let mut count: u32 = 0;
let result = unsafe { CGGetActiveDisplayList(0, ptr::null_mut(), &mut count) };
if result != 0 {
return Ok(Vec::new());
}
let mut ids = vec![0u32; count as usize];
let result = unsafe { CGGetActiveDisplayList(count, ids.as_mut_ptr(), &mut count) };
if result != 0 {
return Ok(Vec::new());
}
ids.truncate(count as usize);
let labels = unsafe { screen_id_to_human_label() };
let devices = ids
.into_iter()
.map(|id| {
let _bounds = unsafe { CGDisplayBounds(id) };
let name = labels
.get(&id)
.map(|m| m.label.to_string())
.unwrap_or_else(|| format!("Display {}", id));
CaptureDeviceInfo {
id: id.to_string(),
name,
kind: CaptureDeviceKind::Screen,
is_available: true,
}
})
.collect();
Ok(devices)
}
CaptureDeviceKind::Window => Ok(Vec::new()),
_ => Ok(Vec::new()),
}
}
}
impl CaptureBackend for MacScreenCaptureBackend {
fn create_session(&self, config: &CaptureConfig) -> Result<Box<dyn CaptureSession>> {
Ok(Box::new(MacScreenCaptureSession::new(config.clone())))
}
}
struct MacScreenCaptureSession {
config: CaptureConfig,
state: CaptureSessionState,
dropped: AtomicU64,
latency_ms: AtomicU64,
callback: Option<FrameCallback>,
}
impl MacScreenCaptureSession {
fn new(config: CaptureConfig) -> Self {
Self {
config,
state: CaptureSessionState::Idle,
dropped: AtomicU64::new(0),
latency_ms: AtomicU64::new(0),
callback: None,
}
}
}
impl CaptureSession for MacScreenCaptureSession {
fn start(&mut self, config: CaptureConfig, callback: FrameCallback) -> Result<()> {
self.config = config;
self.state = CaptureSessionState::Starting;
self.callback = Some(callback);
self.state = CaptureSessionState::Running;
Ok(())
}
fn pause(&mut self) -> Result<()> {
self.state = CaptureSessionState::Paused;
Ok(())
}
fn resume(&mut self) -> Result<()> {
self.state = CaptureSessionState::Running;
Ok(())
}
fn stop(&mut self) -> Result<()> {
self.state = CaptureSessionState::Stopped;
self.callback = None;
Ok(())
}
fn state(&self) -> CaptureSessionState {
self.state
}
fn dropped_frame_count(&self) -> u64 {
self.dropped.load(Ordering::Relaxed)
}
fn latency_ms(&self) -> u64 {
self.latency_ms.load(Ordering::Relaxed)
}
}