gstreamer-rs/examples/src/glupload.rs
2021-08-03 10:08:32 +02:00

717 lines
24 KiB
Rust

// This example demonstrates how to output GL textures, within an
// EGL/X11 context provided by the application, and render those
// textures in the GL application.
// {videotestsrc} - { glsinkbin }
use gst::element_error;
use gst_gl::prelude::*;
use std::ffi::CStr;
use std::mem;
use std::ptr;
use std::sync;
use anyhow::Error;
use derive_more::{Display, Error};
#[derive(Debug, Display, Error)]
#[display(fmt = "Missing element {}", _0)]
struct MissingElement(#[error(not(source))] &'static str);
#[derive(Debug, Display, Error)]
#[display(fmt = "Received error from {}: {} (debug: {:?})", src, error, debug)]
struct ErrorMessage {
src: String,
error: String,
debug: Option<String>,
source: glib::Error,
}
#[rustfmt::skip]
static VERTICES: [f32; 20] = [
1.0, 1.0, 0.0, 1.0, 0.0,
-1.0, 1.0, 0.0, 0.0, 0.0,
-1.0, -1.0, 0.0, 0.0, 1.0,
1.0, -1.0, 0.0, 1.0, 1.0,
];
static INDICES: [u16; 6] = [0, 1, 2, 0, 2, 3];
#[rustfmt::skip]
static IDENTITY: [f32; 16] = [
1.0, 0.0, 0.0, 0.0,
0.0, 1.0, 0.0, 0.0,
0.0, 0.0, 1.0, 0.0,
0.0, 0.0, 0.0, 1.0,
];
const VS_SRC: &[u8] = b"
uniform mat4 u_transformation;
attribute vec4 a_position;
attribute vec2 a_texcoord;
varying vec2 v_texcoord;
void main() {
gl_Position = u_transformation * a_position;
v_texcoord = a_texcoord;
}
\0";
const FS_SRC: &[u8] = b"
#ifdef GL_ES
precision mediump float;
#endif
varying vec2 v_texcoord;
uniform sampler2D tex;
void main() {
gl_FragColor = texture2D(tex, v_texcoord);
}
\0";
#[allow(clippy::unreadable_literal)]
#[allow(clippy::unused_unit)]
#[allow(clippy::too_many_arguments)]
#[allow(clippy::manual_non_exhaustive)]
#[allow(clippy::upper_case_acronyms)]
pub(crate) mod gl {
pub use self::Gles2 as Gl;
include!(concat!(env!("OUT_DIR"), "/test_gl_bindings.rs"));
}
struct Gl {
gl: gl::Gl,
program: gl::types::GLuint,
attr_position: gl::types::GLint,
attr_texture: gl::types::GLint,
vao: Option<gl::types::GLuint>,
vertex_buffer: gl::types::GLuint,
vbo_indices: gl::types::GLuint,
}
impl Gl {
fn draw_frame(&self, texture_id: gl::types::GLuint) {
unsafe {
// render
self.gl.ClearColor(0.0, 0.0, 0.0, 1.0);
self.gl.Clear(gl::COLOR_BUFFER_BIT);
self.gl.BlendColor(0.0, 0.0, 0.0, 1.0);
if self.gl.BlendFuncSeparate.is_loaded() {
self.gl.BlendFuncSeparate(
gl::SRC_ALPHA,
gl::CONSTANT_COLOR,
gl::ONE,
gl::ONE_MINUS_SRC_ALPHA,
);
} else {
self.gl.BlendFunc(gl::SRC_ALPHA, gl::CONSTANT_COLOR);
}
self.gl.BlendEquation(gl::FUNC_ADD);
self.gl.Enable(gl::BLEND);
self.gl.UseProgram(self.program);
if self.gl.BindVertexArray.is_loaded() {
self.gl.BindVertexArray(self.vao.unwrap());
}
{
self.gl
.BindBuffer(gl::ELEMENT_ARRAY_BUFFER, self.vbo_indices);
self.gl.BindBuffer(gl::ARRAY_BUFFER, self.vertex_buffer);
// Load the vertex position
self.gl.VertexAttribPointer(
self.attr_position as gl::types::GLuint,
3,
gl::FLOAT,
gl::FALSE,
(5 * mem::size_of::<f32>()) as gl::types::GLsizei,
ptr::null(),
);
// Load the texture coordinate
self.gl.VertexAttribPointer(
self.attr_texture as gl::types::GLuint,
2,
gl::FLOAT,
gl::FALSE,
(5 * mem::size_of::<f32>()) as gl::types::GLsizei,
(3 * mem::size_of::<f32>()) as *const () as *const _,
);
self.gl.EnableVertexAttribArray(self.attr_position as _);
self.gl.EnableVertexAttribArray(self.attr_texture as _);
}
self.gl.ActiveTexture(gl::TEXTURE0);
self.gl.BindTexture(gl::TEXTURE_2D, texture_id);
let location = self
.gl
.GetUniformLocation(self.program, b"tex\0".as_ptr() as *const _);
self.gl.Uniform1i(location, 0);
let location = self
.gl
.GetUniformLocation(self.program, b"u_transformation\0".as_ptr() as *const _);
self.gl
.UniformMatrix4fv(location, 1, gl::FALSE, IDENTITY.as_ptr() as *const _);
self.gl
.DrawElements(gl::TRIANGLES, 6, gl::UNSIGNED_SHORT, ptr::null());
self.gl.BindTexture(gl::TEXTURE_2D, 0);
self.gl.UseProgram(0);
if self.gl.BindVertexArray.is_loaded() {
self.gl.BindVertexArray(0);
}
{
self.gl.BindBuffer(gl::ELEMENT_ARRAY_BUFFER, 0);
self.gl.BindBuffer(gl::ARRAY_BUFFER, 0);
self.gl.DisableVertexAttribArray(self.attr_position as _);
self.gl.DisableVertexAttribArray(self.attr_texture as _);
}
}
}
fn resize(&self, size: glutin::dpi::PhysicalSize<u32>) {
unsafe {
self.gl
.Viewport(0, 0, size.width as i32, size.height as i32);
}
}
}
fn load(gl_context: &glutin::WindowedContext<glutin::PossiblyCurrent>) -> Gl {
let gl = gl::Gl::load_with(|ptr| gl_context.get_proc_address(ptr) as *const _);
let version = unsafe {
let data = CStr::from_ptr(gl.GetString(gl::VERSION) as *const _)
.to_bytes()
.to_vec();
String::from_utf8(data).unwrap()
};
println!("OpenGL version {}", version);
let (program, attr_position, attr_texture, vao, vertex_buffer, vbo_indices) = unsafe {
let vs = gl.CreateShader(gl::VERTEX_SHADER);
gl.ShaderSource(vs, 1, [VS_SRC.as_ptr() as *const _].as_ptr(), ptr::null());
gl.CompileShader(vs);
let fs = gl.CreateShader(gl::FRAGMENT_SHADER);
gl.ShaderSource(fs, 1, [FS_SRC.as_ptr() as *const _].as_ptr(), ptr::null());
gl.CompileShader(fs);
let program = gl.CreateProgram();
gl.AttachShader(program, vs);
gl.AttachShader(program, fs);
gl.LinkProgram(program);
{
let mut success: gl::types::GLint = 1;
gl.GetProgramiv(fs, gl::LINK_STATUS, &mut success);
assert!(success != 0);
}
let attr_position = gl.GetAttribLocation(program, b"a_position\0".as_ptr() as *const _);
let attr_texture = gl.GetAttribLocation(program, b"a_texcoord\0".as_ptr() as *const _);
let vao = if gl.BindVertexArray.is_loaded() {
let mut vao = mem::MaybeUninit::uninit();
gl.GenVertexArrays(1, vao.as_mut_ptr());
let vao = vao.assume_init();
gl.BindVertexArray(vao);
Some(vao)
} else {
None
};
let mut vertex_buffer = mem::MaybeUninit::uninit();
gl.GenBuffers(1, vertex_buffer.as_mut_ptr());
let vertex_buffer = vertex_buffer.assume_init();
gl.BindBuffer(gl::ARRAY_BUFFER, vertex_buffer);
gl.BufferData(
gl::ARRAY_BUFFER,
(VERTICES.len() * mem::size_of::<f32>()) as gl::types::GLsizeiptr,
VERTICES.as_ptr() as *const _,
gl::STATIC_DRAW,
);
let mut vbo_indices = mem::MaybeUninit::uninit();
gl.GenBuffers(1, vbo_indices.as_mut_ptr());
let vbo_indices = vbo_indices.assume_init();
gl.BindBuffer(gl::ELEMENT_ARRAY_BUFFER, vbo_indices);
gl.BufferData(
gl::ELEMENT_ARRAY_BUFFER,
(INDICES.len() * mem::size_of::<u16>()) as gl::types::GLsizeiptr,
INDICES.as_ptr() as *const _,
gl::STATIC_DRAW,
);
if gl.BindVertexArray.is_loaded() {
gl.BindBuffer(gl::ELEMENT_ARRAY_BUFFER, vbo_indices);
gl.BindBuffer(gl::ARRAY_BUFFER, vertex_buffer);
// Load the vertex position
gl.VertexAttribPointer(
attr_position as gl::types::GLuint,
3,
gl::FLOAT,
gl::FALSE,
(5 * mem::size_of::<f32>()) as gl::types::GLsizei,
ptr::null(),
);
// Load the texture coordinate
gl.VertexAttribPointer(
attr_texture as gl::types::GLuint,
2,
gl::FLOAT,
gl::FALSE,
(5 * mem::size_of::<f32>()) as gl::types::GLsizei,
(3 * mem::size_of::<f32>()) as *const () as *const _,
);
gl.EnableVertexAttribArray(attr_position as _);
gl.EnableVertexAttribArray(attr_texture as _);
gl.BindVertexArray(0);
}
gl.BindBuffer(gl::ELEMENT_ARRAY_BUFFER, 0);
gl.BindBuffer(gl::ARRAY_BUFFER, 0);
(
program,
attr_position,
attr_texture,
vao,
vertex_buffer,
vbo_indices,
)
};
Gl {
gl,
program,
attr_position,
attr_texture,
vao,
vertex_buffer,
vbo_indices,
}
}
#[derive(Debug)]
enum Message {
Sample(gst::Sample),
BusEvent,
}
pub(crate) struct App {
pipeline: gst::Pipeline,
appsink: gst_app::AppSink,
glupload: gst::Element,
bus: gst::Bus,
event_loop: glutin::event_loop::EventLoop<Message>,
windowed_context: glutin::WindowedContext<glutin::PossiblyCurrent>,
shared_context: gst_gl::GLContext,
}
impl App {
pub(crate) fn new(gl_element: Option<&gst::Element>) -> Result<App, Error> {
gst::init()?;
let (pipeline, appsink, glupload) = App::create_pipeline(gl_element)?;
let bus = pipeline
.bus()
.expect("Pipeline without bus. Shouldn't happen!");
let event_loop = glutin::event_loop::EventLoop::with_user_event();
let window = glutin::window::WindowBuilder::new().with_title("GL rendering");
let windowed_context = glutin::ContextBuilder::new()
.with_vsync(true)
.build_windowed(window, &event_loop)?;
let windowed_context = unsafe { windowed_context.make_current().map_err(|(_, err)| err)? };
#[cfg(any(feature = "gst-gl-x11", feature = "gst-gl-wayland"))]
let inner_window = windowed_context.window();
let shared_context: gst_gl::GLContext;
if cfg!(target_os = "linux") {
use glutin::platform::unix::RawHandle;
#[cfg(any(feature = "gst-gl-x11", feature = "gst-gl-wayland"))]
use glutin::platform::unix::WindowExtUnix;
use glutin::platform::ContextTraitExt;
let api = App::map_gl_api(windowed_context.get_api());
let (gl_context, gl_display, platform) = match unsafe { windowed_context.raw_handle() }
{
#[cfg(any(feature = "gst-gl-egl", feature = "gst-gl-wayland"))]
RawHandle::Egl(egl_context) => {
let mut gl_display = None;
#[cfg(feature = "gst-gl-egl")]
if let Some(display) = unsafe { windowed_context.get_egl_display() } {
gl_display = Some(
unsafe { gst_gl_egl::GLDisplayEGL::with_egl_display(display as usize) }
.unwrap()
.upcast::<gst_gl::GLDisplay>(),
)
};
#[cfg(feature = "gst-gl-wayland")]
if let Some(display) = inner_window.wayland_display() {
gl_display = Some(
unsafe {
gst_gl_wayland::GLDisplayWayland::with_display(display as usize)
}
.unwrap()
.upcast::<gst_gl::GLDisplay>(),
)
};
(
egl_context as usize,
gl_display.expect("Could not retrieve GLDisplay through EGL context and/or Wayland display"),
gst_gl::GLPlatform::EGL,
)
}
#[cfg(feature = "gst-gl-x11")]
RawHandle::Glx(glx_context) => {
let gl_display = if let Some(display) = inner_window.xlib_display() {
unsafe { gst_gl_x11::GLDisplayX11::with_display(display as usize) }.unwrap()
} else {
panic!("X11 window without X Display");
};
(
glx_context as usize,
gl_display.upcast::<gst_gl::GLDisplay>(),
gst_gl::GLPlatform::GLX,
)
}
#[allow(unreachable_patterns)]
handler => panic!("Unsupported platform: {:?}.", handler),
};
shared_context =
unsafe { gst_gl::GLContext::new_wrapped(&gl_display, gl_context, platform, api) }
.unwrap();
shared_context
.activate(true)
.expect("Couldn't activate wrapped GL context");
shared_context.fill_info()?;
let gl_context = shared_context.clone();
let event_proxy = sync::Mutex::new(event_loop.create_proxy());
#[allow(clippy::single_match)]
bus.set_sync_handler(move |_, msg| {
match msg.view() {
gst::MessageView::NeedContext(ctxt) => {
let context_type = ctxt.context_type();
if context_type == *gst_gl::GL_DISPLAY_CONTEXT_TYPE {
if let Some(el) =
msg.src().map(|s| s.downcast::<gst::Element>().unwrap())
{
let context = gst::Context::new(context_type, true);
context.set_gl_display(&gl_display);
el.set_context(&context);
}
}
if context_type == "gst.gl.app_context" {
if let Some(el) =
msg.src().map(|s| s.downcast::<gst::Element>().unwrap())
{
let mut context = gst::Context::new(context_type, true);
{
let context = context.get_mut().unwrap();
let s = context.structure_mut();
s.set("context", &gl_context);
}
el.set_context(&context);
}
}
}
_ => (),
}
if let Err(e) = event_proxy.lock().unwrap().send_event(Message::BusEvent) {
eprintln!("Failed to send BusEvent to event proxy: {}", e)
}
gst::BusSyncReply::Pass
});
} else {
panic!("This example only has Linux support");
}
Ok(App {
pipeline,
appsink,
glupload,
bus,
event_loop,
windowed_context,
shared_context,
})
}
fn setup(&self, event_loop: &glutin::event_loop::EventLoop<Message>) -> Result<(), Error> {
let event_proxy = event_loop.create_proxy();
self.appsink.set_callbacks(
gst_app::AppSinkCallbacks::builder()
.new_sample(move |appsink| {
let sample = appsink.pull_sample().map_err(|_| gst::FlowError::Eos)?;
{
let _buffer = sample.buffer().ok_or_else(|| {
element_error!(
appsink,
gst::ResourceError::Failed,
("Failed to get buffer from appsink")
);
gst::FlowError::Error
})?;
let _info = sample
.caps()
.and_then(|caps| gst_video::VideoInfo::from_caps(caps).ok())
.ok_or_else(|| {
element_error!(
appsink,
gst::ResourceError::Failed,
("Failed to get video info from sample")
);
gst::FlowError::Error
})?;
}
event_proxy
.send_event(Message::Sample(sample))
.map(|()| gst::FlowSuccess::Ok)
.map_err(|e| {
element_error!(
appsink,
gst::ResourceError::Failed,
("Failed to send sample to event loop: {}", e)
);
gst::FlowError::Error
})
})
.build(),
);
self.pipeline.set_state(gst::State::Playing)?;
Ok(())
}
fn map_gl_api(api: glutin::Api) -> gst_gl::GLAPI {
match api {
glutin::Api::OpenGl => gst_gl::GLAPI::OPENGL3,
glutin::Api::OpenGlEs => gst_gl::GLAPI::GLES2,
_ => gst_gl::GLAPI::empty(),
}
}
fn create_pipeline(
gl_element: Option<&gst::Element>,
) -> Result<(gst::Pipeline, gst_app::AppSink, gst::Element), Error> {
let pipeline = gst::Pipeline::new(None);
let src = gst::ElementFactory::make("videotestsrc", None)
.map_err(|_| MissingElement("videotestsrc"))?;
let appsink = gst::ElementFactory::make("appsink", None)
.map_err(|_| MissingElement("appsink"))?
.dynamic_cast::<gst_app::AppSink>()
.expect("Sink element is expected to be an appsink!");
appsink.set_property("enable-last-sample", &false)?;
appsink.set_property("emit-signals", &false)?;
appsink.set_property("max-buffers", &1u32)?;
let caps = gst::Caps::builder("video/x-raw")
.features(&[&gst_gl::CAPS_FEATURE_MEMORY_GL_MEMORY])
.field("format", &gst_video::VideoFormat::Rgba.to_str())
.field("texture-target", &"2D")
.build();
appsink.set_caps(Some(&caps));
if let Some(gl_element) = gl_element {
let glupload = gst::ElementFactory::make("glupload", None)
.map_err(|_| MissingElement("glupload"))?;
pipeline.add_many(&[&src, &glupload])?;
pipeline.add(gl_element)?;
pipeline.add(&appsink)?;
src.link(&glupload)?;
glupload.link(gl_element)?;
gl_element.link(&appsink)?;
Ok((pipeline, appsink, glupload))
} else {
let sink = gst::ElementFactory::make("glsinkbin", None)
.map_err(|_| MissingElement("glsinkbin"))?;
sink.set_property("sink", &appsink)?;
pipeline.add_many(&[&src, &sink])?;
src.link(&sink)?;
// get the glupload element to extract later the used context in it
let mut iter = sink.dynamic_cast::<gst::Bin>().unwrap().iterate_elements();
let glupload = loop {
match iter.next() {
Ok(Some(element)) => {
if "glupload" == element.factory().unwrap().name() {
break Some(element);
}
}
Err(gst::IteratorError::Resync) => iter.resync(),
_ => break None,
}
};
Ok((pipeline, appsink, glupload.unwrap()))
}
}
fn handle_messages(bus: &gst::Bus) -> Result<(), Error> {
use gst::MessageView;
for msg in bus.iter() {
match msg.view() {
MessageView::Eos(..) => break,
MessageView::Error(err) => {
return Err(ErrorMessage {
src: msg
.src()
.map(|s| String::from(s.path_string()))
.unwrap_or_else(|| String::from("None")),
error: err.error().to_string(),
debug: err.debug(),
source: err.error(),
}
.into());
}
_ => (),
}
}
Ok(())
}
}
pub(crate) fn main_loop(app: App) -> Result<(), Error> {
app.setup(&app.event_loop)?;
println!(
"Pixel format of the window's GL context {:?}",
app.windowed_context.get_pixel_format()
);
let gl = load(&app.windowed_context);
let mut curr_frame: Option<gst_video::VideoFrame<gst_video::video_frame::Readable>> = None;
let mut gst_gl_context: Option<gst_gl::GLContext> = None;
let App {
bus,
event_loop,
glupload,
pipeline,
shared_context,
windowed_context,
..
} = app;
event_loop.run(move |event, _, cf| {
*cf = glutin::event_loop::ControlFlow::Wait;
let mut needs_redraw = false;
match event {
glutin::event::Event::LoopDestroyed => {
pipeline.send_event(gst::event::Eos::new());
pipeline.set_state(gst::State::Null).unwrap();
}
glutin::event::Event::WindowEvent { event, .. } => match event {
glutin::event::WindowEvent::CloseRequested
| glutin::event::WindowEvent::KeyboardInput {
input:
glutin::event::KeyboardInput {
state: glutin::event::ElementState::Released,
virtual_keycode: Some(glutin::event::VirtualKeyCode::Escape),
..
},
..
} => *cf = glutin::event_loop::ControlFlow::Exit,
glutin::event::WindowEvent::Resized(physical_size) => {
windowed_context.resize(physical_size);
gl.resize(physical_size);
}
_ => (),
},
glutin::event::Event::RedrawRequested(_) => needs_redraw = true,
// Receive a frame
glutin::event::Event::UserEvent(Message::Sample(sample)) => {
let buffer = sample.buffer_owned().unwrap();
let info = sample
.caps()
.and_then(|caps| gst_video::VideoInfo::from_caps(caps).ok())
.unwrap();
{
if gst_gl_context.is_none() {
gst_gl_context = glupload
.property("context")
.unwrap()
.get::<Option<gst_gl::GLContext>>()
.unwrap();
}
let sync_meta = buffer.meta::<gst_gl::GLSyncMeta>().unwrap();
sync_meta.set_sync_point(gst_gl_context.as_ref().unwrap());
}
if let Ok(frame) = gst_video::VideoFrame::from_buffer_readable_gl(buffer, &info) {
curr_frame = Some(frame);
needs_redraw = true;
}
}
// Handle all pending messages when we are awaken by set_sync_handler
glutin::event::Event::UserEvent(Message::BusEvent) => {
App::handle_messages(&bus).unwrap();
}
_ => (),
}
if needs_redraw {
if let Some(frame) = curr_frame.as_ref() {
let sync_meta = frame.buffer().meta::<gst_gl::GLSyncMeta>().unwrap();
sync_meta.wait(&shared_context);
if let Some(texture) = frame.texture_id(0) {
gl.draw_frame(texture as gl::types::GLuint);
}
}
windowed_context.swap_buffers().unwrap();
}
})
}