From 936f04cececd2e29177d9189f25487e623ff7240 Mon Sep 17 00:00:00 2001
From: barnold1953 <brb555@utk.edu>
Date: Mon, 9 Jun 2014 11:55:29 -0700
Subject: [PATCH] Simple raypicking for scripts with oculus rift.

---
 interface/src/Camera.cpp                |  8 +++++++-
 interface/src/ui/ApplicationOverlay.cpp | 21 +++++++++++++++++++--
 interface/src/ui/ApplicationOverlay.h   |  3 ++-
 3 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/interface/src/Camera.cpp b/interface/src/Camera.cpp
index f9ee5bdd25..0e33e14f32 100644
--- a/interface/src/Camera.cpp
+++ b/interface/src/Camera.cpp
@@ -18,6 +18,7 @@
 #include "Camera.h"
 #include "Menu.h"
 #include "Util.h"
+#include "devices/OculusManager.h"
 
 const float CAMERA_FIRST_PERSON_MODE_UP_SHIFT  = 0.0f;
 const float CAMERA_FIRST_PERSON_MODE_DISTANCE  = 0.0f;
@@ -264,7 +265,12 @@ PickRay CameraScriptableObject::computePickRay(float x, float y) {
     float screenWidth = Application::getInstance()->getGLWidget()->width();
     float screenHeight = Application::getInstance()->getGLWidget()->height();
     PickRay result;
-    _viewFrustum->computePickRay(x / screenWidth, y / screenHeight, result.origin, result.direction);
+    if (OculusManager::isConnected()) {
+        result.origin = _camera->getPosition();
+        Application::getInstance()->getApplicationOverlay().computeOculusPickRay(x / screenWidth, y / screenHeight, result.direction);
+    } else {
+        _viewFrustum->computePickRay(x / screenWidth, y / screenHeight, result.origin, result.direction);
+    }
     return result;
 }
 
diff --git a/interface/src/ui/ApplicationOverlay.cpp b/interface/src/ui/ApplicationOverlay.cpp
index 49ec8ecddb..f5de7459a8 100644
--- a/interface/src/ui/ApplicationOverlay.cpp
+++ b/interface/src/ui/ApplicationOverlay.cpp
@@ -297,6 +297,25 @@ void ApplicationOverlay::displayOverlayTexture(Camera& whichCamera) {
     glDisable(GL_TEXTURE_2D);
 }
 
+const float textureFov = PI / 2.5f;
+
+void ApplicationOverlay::computeOculusPickRay(float x, float y, glm::vec3& direction) const {
+    glm::quat rot = Application::getInstance()->getAvatar()->getOrientation();
+
+    //invert y direction
+    y = 1.0 - y;
+
+    //Get position on hemisphere UI
+    x = sin((x - 0.5f) * textureFov);
+    y = sin((y - 0.5f) * textureFov);
+
+    float dist = sqrt(x * x + y * y);
+    float z = -sqrt(1.0f - dist * dist);
+
+    //Rotate the UI pick ray by the avatar orientation
+    direction = glm::normalize(rot * glm::vec3(x, y, z));
+}
+
 // Fast helper functions
 inline float max(float a, float b) {
     return (a > b) ? a : b;
@@ -306,8 +325,6 @@ inline float min(float a, float b) {
     return (a < b) ? a : b;
 }
 
-const float textureFov = PI / 2.5f;
-
 // Draws the FBO texture for Oculus rift. TODO: Draw a curved texture instead of plane.
 void ApplicationOverlay::displayOverlayTextureOculus(Camera& whichCamera) {
 
diff --git a/interface/src/ui/ApplicationOverlay.h b/interface/src/ui/ApplicationOverlay.h
index 8817549277..1bf0e18816 100644
--- a/interface/src/ui/ApplicationOverlay.h
+++ b/interface/src/ui/ApplicationOverlay.h
@@ -15,7 +15,7 @@
 class Overlays;
 class QOpenGLFramebufferObject;
 
-// Handles the drawing of the overlays to the scree
+// Handles the drawing of the overlays to the screen
 class ApplicationOverlay {
 public:
 
@@ -27,6 +27,7 @@ public:
     void renderOverlay(bool renderToTexture = false);
     void displayOverlayTexture(Camera& whichCamera);
     void displayOverlayTextureOculus(Camera& whichCamera);
+    void computeOculusPickRay(float x, float y, glm::vec3& direction) const;
 
     // Getters
     QOpenGLFramebufferObject* getFramebufferObject();