DisplayPlugins: updateHeadPose() no longer returns a value.

Also, moved updateHeadPose so that the overlay and the main rendering use the same headPose.
Which should also be the same place the latencyMarker for the ovr_GetTrackingState is set.

interface/src/Application.cpp

@@ -1418,6 +1418,12 @@ void Application::paintGL() {
     // FIXME not needed anymore?
     _offscreenContext->makeCurrent();
 
+    // Tell the plugin what pose we're using to render.  In this case we're just using the
+    // unmodified head pose because the only plugin that cares (the Oculus plugin) uses it
+    // for rotational timewarp.  If we move to support positonal timewarp, we need to
+    // ensure this contains the full pose composed with the eye offsets.
+    displayPlugin->updateHeadPose(_frameCount);
+
     // update the avatar with a fresh HMD pose
     getMyAvatar()->updateFromHMDSensorMatrix(getHMDSensorPose());
 
@@ -1598,12 +1604,7 @@ void Application::paintGL() {
             auto baseProjection = renderArgs._viewFrustum->getProjection();
             auto hmdInterface = DependencyManager::get<HMDScriptingInterface>();
             float IPDScale = hmdInterface->getIPDScale();
-
-            // Tell the plugin what pose we're using to render.  In this case we're just using the
-            // unmodified head pose because the only plugin that cares (the Oculus plugin) uses it
-            // for rotational timewarp.  If we move to support positonal timewarp, we need to
-            // ensure this contains the full pose composed with the eye offsets.
-            mat4 headPose = displayPlugin->updateHeadPose(_frameCount);
+            mat4 headPose = displayPlugin->getHeadPose();
 
             // FIXME we probably don't need to set the projection matrix every frame,
             // only when the display plugin changes (or in non-HMD modes when the user

libraries/plugins/src/plugins/DisplayPlugin.h

@@ -122,9 +122,7 @@ public:
     }
 
     // will query the underlying hmd api to compute the most recent head pose
-    virtual glm::mat4 updateHeadPose(uint32_t frameIndex) {
-        return glm::mat4();
-    }
+    virtual void updateHeadPose(uint32_t frameIndex) {}
 
     // returns a copy of the most recent head pose, computed via updateHeadPose
     virtual glm::mat4 getHeadPose() const {

plugins/oculus/src/OculusBaseDisplayPlugin.cpp

@@ -15,16 +15,11 @@ void OculusBaseDisplayPlugin::resetSensors() {
     ovr_RecenterPose(_session);
 }
 
-glm::mat4 OculusBaseDisplayPlugin::updateHeadPose(uint32_t frameIndex) {
-    static uint32_t lastFrameSeen = 0;
+void OculusBaseDisplayPlugin::updateHeadPose(uint32_t frameIndex) {
     auto displayTime = ovr_GetPredictedDisplayTime(_session, frameIndex);
-    auto trackingState = ovr_GetTrackingState(_session, displayTime, frameIndex > lastFrameSeen);
-    if (frameIndex > lastFrameSeen) {
-        lastFrameSeen = frameIndex;
-    }
+    auto trackingState = ovr_GetTrackingState(_session, displayTime, true);
     mat4 headPose = toGlm(trackingState.HeadPose.ThePose);
     _headPoseCache.set(headPose);
-    return headPose;
 }
 
 glm::mat4 OculusBaseDisplayPlugin::getHeadPose() const {

plugins/oculus/src/OculusBaseDisplayPlugin.h

@@ -21,7 +21,7 @@ public:
 
     // Stereo specific methods
     virtual void resetSensors() override final;
-    virtual glm::mat4 updateHeadPose(uint32_t frameIndex) override;
+    virtual void updateHeadPose(uint32_t frameIndex) override;
     virtual glm::mat4 getHeadPose() const override;
 
 protected:

plugins/openvr/src/OpenVrDisplayPlugin.cpp

@@ -112,7 +112,7 @@ void OpenVrDisplayPlugin::resetSensors() {
     _sensorResetMat = glm::inverse(cancelOutRollAndPitch(m));
 }
 
-glm::mat4 OpenVrDisplayPlugin::updateHeadPose(uint32_t frameIndex) {
+void OpenVrDisplayPlugin::updateHeadPose(uint32_t frameIndex) {
 
     float displayFrequency = _system->GetFloatTrackedDeviceProperty(vr::k_unTrackedDeviceIndex_Hmd, vr::Prop_DisplayFrequency_Float);
     float frameDuration = 1.f / displayFrequency;
@@ -141,8 +141,6 @@ glm::mat4 OpenVrDisplayPlugin::updateHeadPose(uint32_t frameIndex) {
     }
 
     _headPoseCache.set(_trackedDevicePoseMat4[0]);
-
-    return _trackedDevicePoseMat4[0];
 }
 
 glm::mat4 OpenVrDisplayPlugin::getHeadPose() const {

plugins/openvr/src/OpenVrDisplayPlugin.h

@@ -28,7 +28,7 @@ public:
 
     // Stereo specific methods
     virtual void resetSensors() override;
-    virtual glm::mat4 updateHeadPose(uint32_t frameIndex) override;
+    virtual void updateHeadPose(uint32_t frameIndex) override;
     virtual glm::mat4 getHeadPose() const override;
 
 protected: