1 // Copyright 2013 The Flutter Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "session_connection.h"
6
7 #include "flutter/fml/make_copyable.h"
8 #include "lib/fidl/cpp/optional.h"
9 #include "lib/ui/scenic/cpp/commands.h"
10 #include "vsync_recorder.h"
11 #include "vsync_waiter.h"
12
13 namespace flutter_runner {
14
SessionConnection(std::string debug_label,fuchsia::ui::views::ViewToken view_token,fidl::InterfaceHandle<fuchsia::ui::scenic::Session> session,fml::closure session_error_callback,zx_handle_t vsync_event_handle)15 SessionConnection::SessionConnection(
16 std::string debug_label,
17 fuchsia::ui::views::ViewToken view_token,
18 fidl::InterfaceHandle<fuchsia::ui::scenic::Session> session,
19 fml::closure session_error_callback,
20 zx_handle_t vsync_event_handle)
21 : debug_label_(std::move(debug_label)),
22 session_wrapper_(session.Bind(), nullptr),
23 root_view_(&session_wrapper_, std::move(view_token.value), debug_label),
24 root_node_(&session_wrapper_),
25 surface_producer_(
26 std::make_unique<VulkanSurfaceProducer>(&session_wrapper_)),
27 scene_update_context_(&session_wrapper_, surface_producer_.get()),
28 vsync_event_handle_(vsync_event_handle) {
29 session_wrapper_.set_error_handler(
30 [callback = session_error_callback](zx_status_t status) { callback(); });
31
32 session_wrapper_.SetDebugName(debug_label_);
33
34 // TODO(SCN-975): Re-enable.
35 // view_->GetToken(std::bind(&PlatformView::ConnectSemanticsProvider, this,
36 // std::placeholders::_1));
37
38 root_view_.AddChild(root_node_);
39 root_node_.SetEventMask(fuchsia::ui::gfx::kMetricsEventMask |
40 fuchsia::ui::gfx::kSizeChangeHintEventMask);
41
42 // Signal is initially high indicating availability of the session.
43 ToggleSignal(vsync_event_handle_, true);
44
45 PresentSession();
46 }
47
48 SessionConnection::~SessionConnection() = default;
49
Present(flutter::CompositorContext::ScopedFrame & frame)50 void SessionConnection::Present(
51 flutter::CompositorContext::ScopedFrame& frame) {
52 TRACE_EVENT0("gfx", "SessionConnection::Present");
53 TRACE_FLOW_BEGIN("gfx", "SessionConnection::PresentSession",
54 next_present_session_trace_id_);
55
56 // Throttle vsync if presentation callback is already pending. This allows
57 // the paint tasks for this frame to execute in parallel with presentation
58 // of last frame but still provides back-pressure to prevent us from queuing
59 // even more work.
60 if (presentation_callback_pending_) {
61 present_session_pending_ = true;
62 ToggleSignal(vsync_event_handle_, false);
63 } else {
64 PresentSession();
65 }
66
67 // Flush all session ops. Paint tasks have not yet executed but those are
68 // fenced. The compositor can start processing ops while we finalize paint
69 // tasks.
70 PresentSession();
71
72 // Execute paint tasks and signal fences.
73 auto surfaces_to_submit = scene_update_context_.ExecutePaintTasks(frame);
74
75 // Tell the surface producer that a present has occurred so it can perform
76 // book-keeping on buffer caches.
77 surface_producer_->OnSurfacesPresented(std::move(surfaces_to_submit));
78 }
79
OnSessionSizeChangeHint(float width_change_factor,float height_change_factor)80 void SessionConnection::OnSessionSizeChangeHint(float width_change_factor,
81 float height_change_factor) {
82 surface_producer_->OnSessionSizeChangeHint(width_change_factor,
83 height_change_factor);
84 }
85
EnqueueClearOps()86 void SessionConnection::EnqueueClearOps() {
87 // We are going to be sending down a fresh node hierarchy every frame. So just
88 // enqueue a detach op on the imported root node.
89 session_wrapper_.Enqueue(scenic::NewDetachChildrenCmd(root_node_.id()));
90 }
91
PresentSession()92 void SessionConnection::PresentSession() {
93 TRACE_EVENT0("gfx", "SessionConnection::PresentSession");
94 while (processed_present_session_trace_id_ < next_present_session_trace_id_) {
95 TRACE_FLOW_END("gfx", "SessionConnection::PresentSession",
96 processed_present_session_trace_id_);
97 processed_present_session_trace_id_++;
98 }
99 TRACE_FLOW_BEGIN("gfx", "Session::Present", next_present_trace_id_);
100 next_present_trace_id_++;
101
102 // Presentation callback is pending as a result of Present() call below.
103 presentation_callback_pending_ = true;
104
105 // Flush all session ops. Paint tasks may not yet have executed but those are
106 // fenced. The compositor can start processing ops while we finalize paint
107 // tasks.
108 session_wrapper_.Present(
109 0, // presentation_time. (placeholder).
110 [this, handle = vsync_event_handle_](
111 fuchsia::images::PresentationInfo presentation_info) {
112 presentation_callback_pending_ = false;
113 VsyncRecorder::GetInstance().UpdateVsyncInfo(presentation_info);
114 // Process pending PresentSession() calls.
115 if (present_session_pending_) {
116 present_session_pending_ = false;
117 PresentSession();
118 }
119 ToggleSignal(handle, true);
120 } // callback
121 );
122
123 // Prepare for the next frame. These ops won't be processed till the next
124 // present.
125 EnqueueClearOps();
126 }
127
ToggleSignal(zx_handle_t handle,bool set)128 void SessionConnection::ToggleSignal(zx_handle_t handle, bool set) {
129 const auto signal = VsyncWaiter::SessionPresentSignal;
130 auto status = zx_object_signal(handle, // handle
131 set ? 0 : signal, // clear mask
132 set ? signal : 0 // set mask
133 );
134 if (status != ZX_OK) {
135 FML_LOG(ERROR) << "Could not toggle vsync signal: " << set;
136 }
137 }
138
139 } // namespace flutter_runner
140