Auto merge of #20315 - kwonoj:feat-webrender-capture, r=jdm

feat(window): bind hotkey to trigger capture event

<!-- Please describe your changes on the following line: -->
Relates to #20295.

This PR intends to expose additional hotkey to window to allow capture webrender. Internally it adds one new `WindowEvent::CaptureWebRender` for those purpose. I took some liberty to make some decisions around which need to be reviewed & updated in PR.

- `Ctrl-shift-3` is binded to hotkey to follow described in Gecko's behavior. Is it good to go?
- Maybe do not need to create new event `CaptureWebRender` but reuse `ToggleWebRenderDebug`, having additional `WebRenderDebugOption` values?
: This sounds more right path for me, but `capture` isn't really `toggle` behavior to include capture into it.
- Capturing will create `capture_webrender` in cwd, creates new folder inside each time new capture stored
: Maybe it'd better to expose new cmdline args allow overrides, or some better way else. I took the simple approach to generate path without asking for it.

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #20295 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____
- This change has manually verified on local machines (mac, windows, linux).

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.gitignore

@@ -22,6 +22,7 @@
 Servo.app
 .config.mk.last
 /glfw
+capture_webrender/
 
 # Editors
 

Cargo.lock

@@ -2352,6 +2352,14 @@ name = "regex-syntax"
 version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "ron"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "serde 1.0.27 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "rust-webvr"
 version = "0.9.10"
@@ -3492,6 +3500,8 @@ dependencies = [
  "num-traits 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)",
  "plane-split 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rayon 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ron 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.27 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "thread_profiler 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3893,6 +3903,7 @@ dependencies = [
 "checksum ref_slice 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "825740057197b7d43025e7faf6477eaabc03434e153233da02d1f44602f71527"
 "checksum regex 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "1731164734096285ec2a5ec7fea5248ae2f5485b3feeb0115af4fda2183b2d1b"
 "checksum regex-syntax 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ad890a5eef7953f55427c50575c680c42841653abd2b028b68cd223d157f62db"
+"checksum ron 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "da06feaa07f69125ab9ddc769b11de29090122170b402547f64b86fe16ebc399"
 "checksum rust-webvr 0.9.10 (registry+https://github.com/rust-lang/crates.io-index)" = "9629ce5b5c3cda05259d225e639851daf39c55c170358d3056205dd205deaab2"
 "checksum rust-webvr-api 0.9.2 (registry+https://github.com/rust-lang/crates.io-index)" = "712e22ba3c03a7075b40842ae91029a0ab96a81f95e97c0cf623800ec0cbac07"
 "checksum rustc-demangle 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "3058a43ada2c2d0b92b3ae38007a2d0fa5e9db971be260e0171408a4ff471c95"

components/compositing/Cargo.toml

@@ -27,5 +27,5 @@ servo_geometry = {path = "../geometry"}
 servo_url = {path = "../url"}
 style_traits = {path = "../style_traits"}
 time = "0.1.17"
-webrender = {git = "https://github.com/servo/webrender"}
+webrender = {git = "https://github.com/servo/webrender", features = ["capture"]}
 webrender_api = {git = "https://github.com/servo/webrender", features = ["ipc"]}

components/compositing/compositor.rs

@@ -23,6 +23,7 @@ use script_traits::CompositorEvent::{MouseMoveEvent, MouseButtonEvent, TouchEven
 use servo_config::opts;
 use servo_geometry::DeviceIndependentPixel;
 use std::collections::HashMap;
+use std::env;
 use std::fs::File;
 use std::rc::Rc;
 use std::sync::mpsc::Sender;
@@ -30,7 +31,7 @@ use std::time::{Duration, Instant};
 use style_traits::{CSSPixel, DevicePixel, PinchZoomFactor};
 use style_traits::cursor::CursorKind;
 use style_traits::viewport::ViewportConstraints;
-use time::{precise_time_ns, precise_time_s};
+use time::{now, precise_time_ns, precise_time_s};
 use touch::{TouchHandler, TouchAction};
 use webrender;
 use webrender_api::{self, DeviceUintRect, DeviceUintSize, HitTestFlags, HitTestResult};
@@ -1530,6 +1531,17 @@ impl<Window: WindowMethods> IOCompositor<Window> {
         txn.generate_frame();
         self.webrender_api.send_transaction(self.webrender_document, txn);
     }
+
+    pub fn capture_webrender(&mut self) {
+        match env::current_dir() {
+            Ok(current_dir) => {
+                let capture_id = now().to_timespec().sec.to_string();
+                let capture_path = current_dir.join("capture_webrender").join(capture_id);
+                self.webrender_api.save_capture(capture_path, webrender_api::CaptureBits::all());
+            },
+            Err(err) => println!("could not locate path to save captures: {:?}", err)
+        }
+    }
 }
 
 /// Why we performed a composite. This is used for debugging.

components/compositing/windowing.rs

@@ -84,6 +84,8 @@ pub enum WindowEvent {
     SelectBrowser(TopLevelBrowsingContextId),
     /// Toggles a debug flag in WebRender
     ToggleWebRenderDebug(WebRenderDebugOption),
+    /// Capture current WebRender
+    CaptureWebRender,
 }
 
 impl Debug for WindowEvent {
@@ -108,6 +110,7 @@ impl Debug for WindowEvent {
             WindowEvent::CloseBrowser(..) => write!(f, "CloseBrowser"),
             WindowEvent::SelectBrowser(..) => write!(f, "SelectBrowser"),
             WindowEvent::ToggleWebRenderDebug(..) => write!(f, "ToggleWebRenderDebug"),
+            WindowEvent::CaptureWebRender => write!(f, "CaptureWebRender"),
         }
     }
 }

components/servo/lib.rs

@@ -333,6 +333,10 @@ impl<Window> Servo<Window> where Window: WindowMethods + 'static {
                 self.compositor.toggle_webrender_debug(option);
             }
 
+            WindowEvent::CaptureWebRender => {
+                self.compositor.capture_webrender();
+            }
+
             WindowEvent::NewBrowser(url, response_chan) => {
                 let msg = ConstellationMsg::NewBrowser(url, response_chan);
                 if let Err(e) = self.constellation_chan.send(msg) {

ports/servo/glutin_app/window.rs

@@ -1230,6 +1230,9 @@ impl WindowMethods for Window {
                     self.event_queue.borrow_mut().push(WindowEvent::Quit);
                 }
             }
+            (_, Some('3'), _) => if mods ^ KeyModifiers::CONTROL == KeyModifiers::SHIFT {
+                self.event_queue.borrow_mut().push(WindowEvent::CaptureWebRender);
+            }
             (KeyModifiers::CONTROL, None, Key::F10) => {
                 let event = WindowEvent::ToggleWebRenderDebug(WebRenderDebugOption::RenderTargetDebug);
                 self.event_queue.borrow_mut().push(event);