Adding WebVR interface to Blink

Source/modules/vr/HMDVRDevice.cpp

Index: Source/modules/vr/HMDVRDevice.cpp
diff --git a/Source/modules/vr/HMDVRDevice.cpp b/Source/modules/vr/HMDVRDevice.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..2aa73e15e568b9bb06e1312d5e3d2e31a17390ae
--- /dev/null
+++ b/Source/modules/vr/HMDVRDevice.cpp
@@ -0,0 +1,97 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "config.h"
+#include "modules/vr/HMDVRDevice.h"
+
+#include "modules/vr/VRFieldOfView.h"
+#include "public/platform/Platform.h"
+#include "public/platform/WebSize.h"
+
+namespace blink {
+
+HMDVRDevice::HMDVRDevice(VRHardwareUnit* hardwareUnit)
+    : VRDevice(hardwareUnit)
+    , m_dirtyFov(true)
+{
+    m_eyeParametersLeft = VREyeParameters::create();
+    m_eyeParametersRight = VREyeParameters::create();
+}
+
+VREye HMDVRDevice::StringToVREye(const String& whichEye)
+{
+    if (whichEye == "left")
+        return VREyeLeft;
+    if (whichEye == "right")
+        return VREyeRight;
+    return VREyeNone;
+}
+
+void HMDVRDevice::updateFromWebVRDevice(const WebVRDevice& device)
+{
+    VRDevice::updateFromWebVRDevice(device);
+    const blink::WebVRHMDInfo &hmdInfo = device.hmdInfo;
+
+    m_eyeParametersLeft->setFromWebVREyeParameters(hmdInfo.leftEye);
+    m_eyeParametersRight->setFromWebVREyeParameters(hmdInfo.rightEye);
+}
+
+VREyeParameters* HMDVRDevice::getEyeParameters(const String& whichEye)
+{
+    // If we have updated the field of view since the last call recompute the render rects.
+    if (m_dirtyFov) {
+        blink::WebVRVector4 leftRect, rightRect;
+        blink::Platform::current()->getVRRenderTargetRects(index(),
+            m_eyeParametersLeft->currentFieldOfView()->toWebVRFieldOfView(),
+            m_eyeParametersRight->currentFieldOfView()->toWebVRFieldOfView(),
+            &leftRect,
+            &rightRect);
+
+        m_eyeParametersLeft->setRenderRect(leftRect.x, leftRect.y, leftRect.z, leftRect.w);
+        m_eyeParametersRight->setRenderRect(rightRect.x, rightRect.y, rightRect.z, rightRect.w);
+
+        m_dirtyFov = false;
+    }
+
+    switch (StringToVREye(whichEye)) {
+    case VREyeLeft:
+        return m_eyeParametersLeft;
+    case VREyeRight:
+        return m_eyeParametersRight;
+    default:

[Mike West, 2015/03/17 05:25:26]

Nit: Here and elsewhere (like VRHardwareUnit::getFieldOfView), why use 'default'
and not 'VREyeNone'? It doesn't seem like we'll be adding eyes anytime soon,
does it? :)

+        return nullptr;
+    }
+}
+
+void HMDVRDevice::setFieldOfView(VRFieldOfView* leftFov, VRFieldOfView* rightFov)
+{
+    m_dirtyFov = true;
+
+    // FIXME: Clamp to maxFOV
+    if (leftFov) {
+        hardwareUnit()->setFieldOfView(VREyeLeft, leftFov);
+        m_eyeParametersLeft->setCurrentFieldOfView(leftFov);
+    } else {
+        hardwareUnit()->setFieldOfView(VREyeLeft, m_eyeParametersLeft->recommendedFieldOfView());
+        m_eyeParametersLeft->setCurrentFieldOfView(m_eyeParametersLeft->recommendedFieldOfView());
+    }
+
+    if (rightFov) {
+        hardwareUnit()->setFieldOfView(VREyeRight, rightFov);
+        m_eyeParametersLeft->setCurrentFieldOfView(rightFov);
+    } else {
+        hardwareUnit()->setFieldOfView(VREyeRight, m_eyeParametersRight->recommendedFieldOfView());
+        m_eyeParametersRight->setCurrentFieldOfView(m_eyeParametersRight->recommendedFieldOfView());
+    }
+}
+
+void HMDVRDevice::trace(Visitor* visitor)
+{
+    visitor->trace(m_eyeParametersLeft);
+    visitor->trace(m_eyeParametersRight);
+
+    VRDevice::trace(visitor);
+}
+
+} // namespace blink