Add pango-cairo example

This commit is contained in:
Sebastian Dröge 2018-08-28 11:06:01 +03:00
parent 2e139bd202
commit 3119593292
2 changed files with 219 additions and 0 deletions

View file

@ -21,6 +21,9 @@ futures-preview = { version = "0.2", optional = true }
byte-slice-cast = "0.2"
failure = "0.1"
failure_derive = "0.1"
cairo-rs = { git = "https://github.com/gtk-rs/cairo", features=["use_glib"], optional = true }
pango = { git = "https://github.com/gtk-rs/pango", optional = true }
pangocairo = { git = "https://github.com/gtk-rs/pangocairo", optional = true }
[features]
gst-player = ["gstreamer-player"]
@ -34,6 +37,7 @@ gst-rtsp-server = ["gstreamer-rtsp-server"]
gst-rtsp-server-record = ["gstreamer-rtsp-server", "gstreamer-rtsp", "gio"]
default-features = []
v1_10 = ["gstreamer/v1_10"]
pango-cairo = ["pango", "pangocairo", "cairo-rs"]
[badges]
travis-ci = { repository = "sdroege/gstreamer-rs", branch = "master" }
@ -110,3 +114,7 @@ required-features = ["gst-rtsp-server-record"]
[[bin]]
name = "discoverer"
[[bin]]
name = "pango-cairo"
required-features = ["pango-cairo"]

View file

@ -0,0 +1,211 @@
extern crate glib;
extern crate gstreamer as gst;
use gst::prelude::*;
extern crate cairo;
extern crate gstreamer_video as gst_video;
extern crate pango;
use pango::prelude::*;
extern crate pangocairo;
use std::error::Error as StdError;
use std::ops;
use std::sync::{Arc, Mutex};
extern crate failure;
use failure::Error;
#[macro_use]
extern crate failure_derive;
#[path = "../examples-common.rs"]
mod examples_common;
#[derive(Debug, Fail)]
#[fail(display = "Missing element {}", _0)]
struct MissingElement(&'static str);
#[derive(Debug, Fail)]
#[fail(
display = "Received error from {}: {} (debug: {:?})",
src,
error,
debug
)]
struct ErrorMessage {
src: String,
error: String,
debug: Option<String>,
#[cause]
cause: glib::Error,
}
struct DrawingContext {
layout: glib::SendUniqueCell<LayoutWrapper>,
info: Option<gst_video::VideoInfo>,
}
#[derive(Debug)]
struct LayoutWrapper(pango::Layout);
impl ops::Deref for LayoutWrapper {
type Target = pango::Layout;
fn deref(&self) -> &pango::Layout {
&self.0
}
}
unsafe impl glib::SendUnique for LayoutWrapper {
fn is_unique(&self) -> bool {
self.0.ref_count() == 1
}
}
fn create_pipeline() -> Result<gst::Pipeline, Error> {
gst::init()?;
let pipeline = gst::Pipeline::new(None);
let src =
gst::ElementFactory::make("videotestsrc", None).ok_or(MissingElement("videotestsrc"))?;
let overlay =
gst::ElementFactory::make("cairooverlay", None).ok_or(MissingElement("cairooverlay"))?;
let capsfilter =
gst::ElementFactory::make("capsfilter", None).ok_or(MissingElement("capsfilter"))?;
let videoconvert =
gst::ElementFactory::make("videoconvert", None).ok_or(MissingElement("videoconvert"))?;
let sink =
gst::ElementFactory::make("autovideosink", None).ok_or(MissingElement("autovideosink"))?;
pipeline.add_many(&[&src, &overlay, &capsfilter, &videoconvert, &sink])?;
gst::Element::link_many(&[&src, &overlay, &capsfilter, &videoconvert, &sink])?;
let caps = gst::Caps::builder("video/x-raw")
.field("width", &800i32)
.field("height", &800i32)
.build();
capsfilter.set_property("caps", &caps).unwrap();
src.set_property_from_str("pattern", "ball");
let fontmap = pangocairo::FontMap::new().unwrap();
let context = fontmap.create_context().unwrap();
let layout = LayoutWrapper(pango::Layout::new(&context));
let font_desc = pango::FontDescription::from_string("Sans Bold 26");
layout.set_font_description(&font_desc);
layout.set_text("GStreamer");
let drawer = Arc::new(Mutex::new(DrawingContext {
layout: glib::SendUniqueCell::new(layout).unwrap(),
info: None,
}));
let drawer_clone = drawer.clone();
overlay
.connect("draw", false, move |args| {
use std::f64::consts::PI;
let drawer = &drawer_clone;
let drawer = drawer.lock().unwrap();
let _overlay = args[0].get::<gst::Element>().unwrap();
let cr = args[1].get::<cairo::Context>().unwrap();
let timestamp = args[2].get::<gst::ClockTime>().unwrap();
let _duration = args[3].get::<gst::ClockTime>().unwrap();
let info = drawer.info.as_ref().unwrap();
let layout = drawer.layout.borrow();
let angle = 2.0
* PI
* ((timestamp % (10 * gst::SECOND)).unwrap() as f64
/ (10.0 * gst::SECOND_VAL as f64));
cr.translate(info.width() as f64 / 2.0, info.height() as f64 / 2.0);
cr.rotate(angle);
for i in 0..10 {
cr.save();
let angle = (360. * i as f64) / 10.0;
let red = (1.0 + f64::cos((angle - 60.0) * PI / 180.0)) / 2.0;
cr.set_source_rgb(red, 0.0, 1.0 - red);
cr.rotate(angle * PI / 180.0);
pangocairo::functions::update_layout(&cr, &layout);
let (width, _height) = layout.get_size();
cr.move_to(
-(width as f64 / pango::SCALE as f64) / 2.0,
-(info.height() as f64) / 2.0,
);
pangocairo::functions::show_layout(&cr, &layout);
cr.restore();
}
None
}).unwrap();
let drawer_clone = drawer.clone();
overlay
.connect("caps-changed", false, move |args| {
let _overlay = args[0].get::<gst::Element>().unwrap();
let caps = args[1].get::<gst::Caps>().unwrap();
let drawer = &drawer_clone;
let mut drawer = drawer.lock().unwrap();
drawer.info = Some(gst_video::VideoInfo::from_caps(&caps).unwrap());
None
}).unwrap();
Ok(pipeline)
}
fn main_loop(pipeline: gst::Pipeline) -> Result<(), Error> {
pipeline.set_state(gst::State::Playing).into_result()?;
let bus = pipeline
.get_bus()
.expect("Pipeline without bus. Shouldn't happen!");
while let Some(msg) = bus.timed_pop(gst::CLOCK_TIME_NONE) {
use gst::MessageView;
match msg.view() {
MessageView::Eos(..) => break,
MessageView::Error(err) => {
pipeline.set_state(gst::State::Null).into_result()?;
Err(ErrorMessage {
src: err
.get_src()
.map(|s| s.get_path_string())
.unwrap_or_else(|| String::from("None")),
error: err.get_error().description().into(),
debug: err.get_debug(),
cause: err.get_error(),
})?;
}
_ => (),
}
}
pipeline.set_state(gst::State::Null).into_result()?;
Ok(())
}
fn example_main() {
match create_pipeline().and_then(main_loop) {
Ok(r) => r,
Err(e) => eprintln!("Error! {}", e),
}
}
fn main() {
// tutorials_common::run is only required to set up the application environent on macOS
// (but not necessary in normal Cocoa applications where this is set up autmatically)
examples_common::run(example_main);
}