gfx/vr/VRDisplayPresentation.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "VRDisplayPresentation.h"
   8 #include "mozilla/dom/DocGroup.h"
   9 #include "mozilla/dom/Document.h"
  10 #include "mozilla/dom/XRWebGLLayer.h"
  11 #include "mozilla/Unused.h"
  12 #include "VRDisplayClient.h"
  13 #include "VRLayerChild.h"
  14
  15 using namespace mozilla;
  16 using namespace mozilla::gfx;
  17
  18 VRDisplayPresentation::VRDisplayPresentation(
  19     VRDisplayClient* aDisplayClient,
  20     const nsTArray<mozilla::dom::VRLayer>& aLayers, uint32_t aGroup)
  21     : mDisplayClient(aDisplayClient),
  22       mDOMLayers(aLayers.Clone()),
  23       mGroup(aGroup) {
  24   CreateLayers();
  25 }
  26
  27 void VRDisplayPresentation::UpdateLayers(
  28     const nsTArray<mozilla::dom::VRLayer>& aLayers) {
  29   mDOMLayers = aLayers.Clone();
  30   CreateLayers();
  31 }
  32
  33 void VRDisplayPresentation::UpdateXRWebGLLayer(dom::XRWebGLLayer* aLayer) {
  34   VRManagerChild* manager = VRManagerChild::Get();
  35   if (!manager) {
  36     // This should not happen, but let's log it and avoid a crash in case
  37     // of regression.
  38     NS_WARNING("VRManagerChild::Get returned null!");
  39     return;
  40   }
  41
  42   dom::HTMLCanvasElement* canvasElement = aLayer->GetCanvas();
  43
  44   if (mLayers.Length() == 0) {
  45     // WebXR uses a single layer for now.
  46     RefPtr<VRLayerChild> vrLayer =
  47         static_cast<VRLayerChild*>(manager->CreateVRLayer(
  48             mDisplayClient->GetDisplayInfo().GetDisplayID(), mGroup));
  49     mLayers.AppendElement(vrLayer);
  50   }
  51   RefPtr<VRLayerChild> vrLayer = mLayers[0];
  52
  53   Rect leftBounds(0.0, 0.0, 0.5, 1.0);
  54   Rect rightBounds(0.5, 0.0, 0.5, 1.0);
  55
  56   vrLayer->Initialize(canvasElement, leftBounds, rightBounds);
  57   vrLayer->SetXRFramebuffer(aLayer->GetFramebuffer());
  58 }
  59
  60 uint32_t VRDisplayPresentation::GetGroup() const { return mGroup; }
  61
  62 void VRDisplayPresentation::CreateLayers() {
  63   VRManagerChild* manager = VRManagerChild::Get();
  64   if (!manager) {
  65     // This should not happen, but let's log it and avoid a crash in case
  66     // of regression.
  67     NS_WARNING("VRManagerChild::Get returned null!");
  68     return;
  69   }
  70
  71   unsigned int iLayer = 0;
  72   for (dom::VRLayer& layer : mDOMLayers) {
  73     dom::HTMLCanvasElement* canvasElement = layer.mSource;
  74     if (!canvasElement) {
  75       /// XXX In the future we will support WebVR in WebWorkers here
  76       continue;
  77     }
  78
  79     Rect leftBounds(0.0, 0.0, 0.5, 1.0);
  80     if (layer.mLeftBounds.Length() == 4) {
  81       leftBounds.SetRect(layer.mLeftBounds[0], layer.mLeftBounds[1],
  82                          layer.mLeftBounds[2], layer.mLeftBounds[3]);
  83     } else if (layer.mLeftBounds.Length() != 0) {
  84       /**
  85        * We ignore layers with an incorrect number of values.
  86        * In the future, VRDisplay.requestPresent may throw in
  87        * this case.  See https://github.com/w3c/webvr/issues/71
  88        */
  89       continue;
  90     }
  91
  92     Rect rightBounds(0.5, 0.0, 0.5, 1.0);
  93     if (layer.mRightBounds.Length() == 4) {
  94       rightBounds.SetRect(layer.mRightBounds[0], layer.mRightBounds[1],
  95                           layer.mRightBounds[2], layer.mRightBounds[3]);
  96     } else if (layer.mRightBounds.Length() != 0) {
  97       /**
  98        * We ignore layers with an incorrect number of values.
  99        * In the future, VRDisplay.requestPresent may throw in
 100        * this case.  See https://github.com/w3c/webvr/issues/71
 101        */
 102       continue;
 103     }
 104
 105     if (mLayers.Length() <= iLayer) {
 106       // Not enough layers, let's add one
 107       RefPtr<VRLayerChild> vrLayer =
 108           static_cast<VRLayerChild*>(manager->CreateVRLayer(
 109               mDisplayClient->GetDisplayInfo().GetDisplayID(), mGroup));
 110       if (!vrLayer) {
 111         NS_WARNING("CreateVRLayer returned null!");
 112         continue;
 113       }
 114       vrLayer->Initialize(canvasElement, leftBounds, rightBounds);
 115       mLayers.AppendElement(vrLayer);
 116     } else {
 117       // We already have a layer, let's update it
 118       mLayers[iLayer]->Initialize(canvasElement, leftBounds, rightBounds);
 119     }
 120     iLayer++;
 121   }
 122
 123   // Truncate any excess layers that weren't included in the updated list
 124   mLayers.SetLength(iLayer);
 125 }
 126
 127 void VRDisplayPresentation::DestroyLayers() {
 128   for (VRLayerChild* layer : mLayers) {
 129     if (layer->IsIPCOpen()) {
 130       Unused << layer->SendDestroy();
 131     }
 132   }
 133   mLayers.Clear();
 134 }
 135
 136 void VRDisplayPresentation::GetDOMLayers(nsTArray<dom::VRLayer>& result) {
 137   result = mDOMLayers.Clone();
 138 }
 139
 140 VRDisplayPresentation::~VRDisplayPresentation() {
 141   DestroyLayers();
 142   mDisplayClient->PresentationDestroyed();
 143 }
 144
 145 void VRDisplayPresentation::SubmitFrame() {
 146   // Currently only one layer supported, submit only the first
 147   if (mLayers.Length() >= 1) {
 148     VRLayerChild* layer = mLayers.ElementAt(0);
 149     layer->SubmitFrame(mDisplayClient->GetDisplayInfo());
 150   }
 151 }