1 // Copyright 2018 The Chromium 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 "third_party/blink/renderer/modules/xr/xr_canvas_input_provider.h"
6
7 #include "device/vr/public/mojom/vr_service.mojom-blink.h"
8 #include "third_party/blink/renderer/core/dom/events/native_event_listener.h"
9 #include "third_party/blink/renderer/core/events/pointer_event.h"
10 #include "third_party/blink/renderer/core/html/canvas/html_canvas_element.h"
11 #include "third_party/blink/renderer/modules/xr/xr_frame_provider.h"
12 #include "third_party/blink/renderer/modules/xr/xr_input_source.h"
13 #include "third_party/blink/renderer/modules/xr/xr_session.h"
14 #include "third_party/blink/renderer/modules/xr/xr_system.h"
15 #include "third_party/blink/renderer/modules/xr/xr_view.h"
16
17 namespace blink {
18
19 namespace {
20
21 class XRCanvasInputEventListener : public NativeEventListener {
22 public:
XRCanvasInputEventListener(XRCanvasInputProvider * input_provider)23 XRCanvasInputEventListener(XRCanvasInputProvider* input_provider)
24 : input_provider_(input_provider) {}
25
Invoke(ExecutionContext * execution_context,Event * event)26 void Invoke(ExecutionContext* execution_context, Event* event) override {
27 if (!input_provider_->ShouldProcessEvents())
28 return;
29
30 auto* pointer_event = To<PointerEvent>(event);
31 DCHECK(pointer_event);
32 if (!pointer_event->isPrimary())
33 return;
34
35 if (event->type() == event_type_names::kPointerdown) {
36 input_provider_->OnPointerDown(pointer_event);
37 } else if (event->type() == event_type_names::kPointerup ||
38 event->type() == event_type_names::kPointercancel) {
39 input_provider_->OnPointerUp(pointer_event);
40 }
41 }
42
Trace(Visitor * visitor)43 void Trace(Visitor* visitor) override {
44 visitor->Trace(input_provider_);
45 EventListener::Trace(visitor);
46 }
47
48 private:
49 Member<XRCanvasInputProvider> input_provider_;
50 };
51
52 } // namespace
53
XRCanvasInputProvider(XRSession * session,HTMLCanvasElement * canvas)54 XRCanvasInputProvider::XRCanvasInputProvider(XRSession* session,
55 HTMLCanvasElement* canvas)
56 : session_(session), canvas_(canvas) {
57 listener_ = MakeGarbageCollected<XRCanvasInputEventListener>(this);
58 canvas->addEventListener(event_type_names::kPointerdown, listener_);
59 canvas->addEventListener(event_type_names::kPointerup, listener_);
60 canvas->addEventListener(event_type_names::kPointercancel, listener_);
61 }
62
~XRCanvasInputProvider()63 XRCanvasInputProvider::~XRCanvasInputProvider() {}
64
Stop()65 void XRCanvasInputProvider::Stop() {
66 if (!listener_) {
67 return;
68 }
69 canvas_->removeEventListener(event_type_names::kPointerdown, listener_);
70 canvas_->removeEventListener(event_type_names::kPointerup, listener_);
71 canvas_->removeEventListener(event_type_names::kPointercancel, listener_);
72 canvas_ = nullptr;
73 listener_ = nullptr;
74 }
75
ShouldProcessEvents()76 bool XRCanvasInputProvider::ShouldProcessEvents() {
77 // Don't process canvas gestures if there's an active immersive session.
78 return !(session_->xr()->frameProvider()->immersive_session());
79 }
80
OnPointerDown(PointerEvent * event)81 void XRCanvasInputProvider::OnPointerDown(PointerEvent* event) {
82 UpdateInputSource(event);
83 input_source_->OnSelectStart();
84 }
85
OnPointerUp(PointerEvent * event)86 void XRCanvasInputProvider::OnPointerUp(PointerEvent* event) {
87 UpdateInputSource(event);
88 input_source_->OnSelect();
89 ClearInputSource();
90 }
91
GetInputSource()92 XRInputSource* XRCanvasInputProvider::GetInputSource() {
93 return input_source_;
94 }
95
UpdateInputSource(PointerEvent * event)96 void XRCanvasInputProvider::UpdateInputSource(PointerEvent* event) {
97 if (!canvas_)
98 return;
99
100 if (!input_source_) {
101 // XRSession doesn't like source ID's of 0. We should only be processing
102 // Canvas Input events in non-immersive sessions anyway, where we don't
103 // expect other controllers, so this number is somewhat arbitrary anyway.
104 input_source_ = MakeGarbageCollected<XRInputSource>(
105 session_, 1, device::mojom::XRTargetRayMode::TAPPING);
106 session_->AddTransientInputSource(input_source_);
107 }
108
109 // Get the event location relative to the canvas element.
110 double element_x = event->pageX() - canvas_->OffsetLeft();
111 double element_y = event->pageY() - canvas_->OffsetTop();
112
113 // Unproject the event location into a pointer matrix. This takes the 2D
114 // position of the screen interaction and shoves it backwards through the
115 // projection matrix to get a 3D point in space, which is then returned in
116 // matrix form so we can use it as an XRInputSource's pointerMatrix.
117 XRViewData& view = session_->views()[0];
118 TransformationMatrix viewer_from_pointer = view.UnprojectPointer(
119 element_x, element_y, canvas_->OffsetWidth(), canvas_->OffsetHeight());
120
121 // Update the pointer pose in input space. For screen tapping, input
122 // space is equivalent to viewer space.
123 input_source_->SetInputFromPointer(&viewer_from_pointer);
124 }
125
ClearInputSource()126 void XRCanvasInputProvider::ClearInputSource() {
127 session_->RemoveTransientInputSource(input_source_);
128 input_source_ = nullptr;
129 }
130
Trace(Visitor * visitor)131 void XRCanvasInputProvider::Trace(Visitor* visitor) {
132 visitor->Trace(session_);
133 visitor->Trace(canvas_);
134 visitor->Trace(listener_);
135 visitor->Trace(input_source_);
136 }
137
138 } // namespace blink
139