fix gui segfault (VR used before initialization)

applications/gui/src/camera.cpp

@@ -268,7 +268,6 @@ bool ftl::gui::Camera::setVR(bool on) {
 		src_->set("focal", intrinsic(0, 0));
 		src_->set("centre_x", intrinsic(0, 2));
 		src_->set("centre_y", intrinsic(1, 2));
-		LOG(INFO) << intrinsic;
 		
 		intrinsic = getCameraMatrix(screen_->getVR(), vr::Eye_Right);
 		CHECK(intrinsic(0, 2) < 0 && intrinsic(1, 2) < 0);
@@ -376,8 +375,9 @@ const GLTexture &ftl::gui::Camera::captureFrame() {
 	if (src_ && src_->isReady()) {
 		UNIQUE_LOCK(mutex_, lk);
 
-		if (isVR()) {
+		if (screen_->isVR()) {
 			#ifdef HAVE_OPENVR
+			
 			vr::VRCompositor()->WaitGetPoses(rTrackedDevicePose_, vr::k_unMaxTrackedDeviceCount, NULL, 0 );
 
 			if ((channel_ == Channel::Right) && rTrackedDevicePose_[vr::k_unTrackedDeviceIndex_Hmd].bPoseIsValid )

applications/gui/src/media_panel.cpp

@@ -149,7 +149,7 @@ MediaPanel::MediaPanel(ftl::gui::Screen *screen) : nanogui::Window(screen, ""),
 		auto button_vr = new Button(this, "VR");
 		button_vr->setFlags(Button::ToggleButton);
 		button_vr->setChangeCallback([this, button_vr](bool state) {
-			if (!screen_->useVR()) {
+			if (!screen_->isVR()) {
 				if (screen_->switchVR(true) == true) {
 					button_vr->setTextColor(nanogui::Color(0.5f,0.5f,1.0f,1.0f));
 					this->button_channels_->setEnabled(false);

applications/gui/src/screen.cpp

@@ -319,14 +319,14 @@ bool ftl::gui::Screen::initVR() {
 	return true;
 }
 
-bool ftl::gui::Screen::useVR() {
+bool ftl::gui::Screen::isVR() {
 	auto *cam = activeCamera();
 	if (HMD_ == nullptr || cam == nullptr) { return false; }
 	return cam->isVR();
 }
 
 bool ftl::gui::Screen::switchVR(bool on) {
-	if (useVR() == on) { return on; }
+	if (isVR() == on) { return on; }
 
 	if (on && (HMD_ == nullptr) && !initVR()) {
 		return false;
@@ -338,7 +338,7 @@ bool ftl::gui::Screen::switchVR(bool on) {
 		activeCamera()->setVR(false);
 	}
 	
-	return useVR();
+	return isVR();
 }
 #endif
 
@@ -466,7 +466,7 @@ void ftl::gui::Screen::draw(NVGcontext *ctx) {
 		if (camera_->getChannel() != ftl::codecs::Channel::Left) { mImageID = rightEye_; }
 
 		#ifdef HAVE_OPENVR
-		if (useVR() && imageSize[0] > 0 && camera_->getLeft().isValid() && camera_->getRight().isValid()) {
+		if (isVR() && imageSize[0] > 0 && camera_->getLeft().isValid() && camera_->getRight().isValid()) {
 			
 			vr::Texture_t leftEyeTexture = {(void*)(uintptr_t)leftEye_, vr::TextureType_OpenGL, vr::ColorSpace_Gamma };
 			vr::VRCompositor()->Submit(vr::Eye_Left, &leftEyeTexture );

applications/gui/src/screen.hpp

@@ -52,7 +52,7 @@ class Screen : public nanogui::Screen {
 	bool hasVR() const { return has_vr_; }
 
 	// is VR mode on/off
-	bool useVR();
+	bool isVR();
 
 	// toggle VR on/off
 	bool switchVR(bool mode);