"Laser pointer" for transmitter.

interface/src/Application.cpp

@@ -1384,7 +1384,9 @@ Avatar* Application::isLookingAtOtherAvatar(glm::vec3& mouseRayOrigin, glm::vec3
         if (node->getLinkedData() != NULL && node->getType() == NODE_TYPE_AGENT) {
             Avatar* avatar = (Avatar *) node->getLinkedData();
             glm::vec3 headPosition = avatar->getHead().getPosition();
-            if (rayIntersectsSphere(mouseRayOrigin, mouseRayDirection, headPosition, HEAD_SPHERE_RADIUS * avatar->getScale())) {
+            float distance;
+            if (rayIntersectsSphere(mouseRayOrigin, mouseRayDirection, headPosition,
+                    HEAD_SPHERE_RADIUS * avatar->getScale(), distance)) {
                 eyePosition = avatar->getHead().getEyePosition();
                 _lookatIndicatorScale = avatar->getScale();
                 _lookatOtherPosition = headPosition;
@@ -1722,6 +1724,40 @@ void Application::update(float deltaTime) {
         _myAvatar.simulate(deltaTime, NULL, Menu::getInstance()->getGyroCameraSensitivity());
     }
     
+    // no transmitter drive implies transmitter pick
+    if (!Menu::getInstance()->isOptionChecked(MenuOption::TransmitterDrive) && _myTransmitter.isConnected()) {
+        _transmitterPickStart = _myAvatar.getSkeleton().joint[AVATAR_JOINT_CHEST].position;
+        glm::vec3 direction = _myAvatar.getOrientation() *
+            glm::quat(glm::radians(_myTransmitter.getEstimatedRotation())) * IDENTITY_FRONT;
+        
+        // check against voxels, avatars
+        const float MAX_PICK_DISTANCE = 100.0f;
+        float minDistance = MAX_PICK_DISTANCE;
+        VoxelDetail detail;
+        float distance;
+        BoxFace face;
+        if (_voxels.findRayIntersection(_transmitterPickStart, direction, detail, distance, face)) {
+            minDistance = min(minDistance, distance);
+        }
+        for(NodeList::iterator node = nodeList->begin(); node != nodeList->end(); node++) {
+            node->lock();
+            if (node->getLinkedData() != NULL) {
+                Avatar *avatar = (Avatar*)node->getLinkedData();
+                if (!avatar->isInitialized()) {
+                    avatar->init();
+                }
+                if (avatar->findRayIntersection(_transmitterPickStart, direction, distance)) {
+                    minDistance = min(minDistance, distance);
+                }
+            }
+            node->unlock();
+        }
+        _transmitterPickEnd = _transmitterPickStart + direction * minDistance;
+        
+    } else {
+        _transmitterPickStart = _transmitterPickEnd = glm::vec3();
+    }
+    
     if (!OculusManager::isConnected()) {        
         if (Menu::getInstance()->isOptionChecked(MenuOption::Mirror)) {
             if (_myCamera.getMode() != CAMERA_MODE_MIRROR) {
@@ -2271,6 +2307,27 @@ void Application::displaySide(Camera& whichCamera) {
     }
         
     renderFollowIndicator();
+    
+    // render transmitter pick ray, if non-empty
+    if (_transmitterPickStart != _transmitterPickEnd) {
+        Glower glower;
+        float TRANSMITTER_PICK_COLOR[] = { 1.0f, 1.0f, 0.0f };
+        glColor3fv(TRANSMITTER_PICK_COLOR);
+        glLineWidth(3.0f);
+        glBegin(GL_LINES);
+        glVertex3f(_transmitterPickStart.x, _transmitterPickStart.y, _transmitterPickStart.z);
+        glVertex3f(_transmitterPickEnd.x, _transmitterPickEnd.y, _transmitterPickEnd.z);
+        glEnd();
+        glLineWidth(1.0f);
+        
+        glPushMatrix();
+        glTranslatef(_transmitterPickEnd.x, _transmitterPickEnd.y, _transmitterPickEnd.z);
+        
+        float PICK_END_RADIUS = 0.025f;
+        glutSolidSphere(PICK_END_RADIUS, 8, 8);
+        
+        glPopMatrix();
+    }
 }
 
 void Application::displayOverlay() {

interface/src/Application.h

@@ -298,6 +298,9 @@ private:
     glm::vec3 _lookatOtherPosition;
     float _lookatIndicatorScale;
     
+    glm::vec3 _transmitterPickStart;
+    glm::vec3 _transmitterPickEnd;
+    
     bool _perfStatsOn; //  Do we want to display perfStats? 
     
     ChatEntry _chatEntry; // chat entry field 

interface/src/Util.cpp

@@ -598,13 +598,35 @@ float loadSetting(QSettings* settings, const char* name, float defaultValue) {
     return value;
 }
 
-bool rayIntersectsSphere(glm::vec3& rayStarting, glm::vec3& rayNormalizedDirection, glm::vec3& sphereCenter, double sphereRadius) {
-    glm::vec3 vecFromRayToSphereCenter = sphereCenter - rayStarting;
-    double projection = glm::dot(vecFromRayToSphereCenter, rayNormalizedDirection);
-    double shortestDistance = sqrt(glm::dot(vecFromRayToSphereCenter, vecFromRayToSphereCenter) - projection * projection);
-    if (shortestDistance <= sphereRadius) {
-        return true;
+bool rayIntersectsSphere(const glm::vec3& rayStarting, const glm::vec3& rayNormalizedDirection,
+        const glm::vec3& sphereCenter, float sphereRadius, float& distance) {
+    glm::vec3 relativeOrigin = rayStarting - sphereCenter;
+    
+    // compute the b, c terms of the quadratic equation (a is dot(direction, direction), which is one)
+    float b = 2.0f * glm::dot(rayNormalizedDirection, relativeOrigin);
+    float c = glm::dot(relativeOrigin, relativeOrigin) - sphereRadius * sphereRadius;
+    
+    // compute the radicand of the quadratic.  if less than zero, there's no intersection
+    float radicand = b * b - 4.0f * c;
+    if (radicand < 0.0f) {
+        return false;
     }
+    
+    // compute the first solution of the quadratic
+    float root = sqrtf(radicand);
+    float firstSolution = -b - root;
+    if (firstSolution > 0.0f) {
+        distance = firstSolution / 2.0f; 
+        return true; // origin is outside the sphere
+    }
+    
+    // now try the second solution
+    float secondSolution = -b + root;
+    if (secondSolution > 0.0f) {
+        distance = 0.0f;
+        return true; // origin is inside the sphere
+    }
+    
     return false;
 }
 
@@ -615,4 +637,4 @@ bool pointInSphere(glm::vec3& point, glm::vec3& sphereCenter, double sphereRadiu
         return true;
     }
     return false;
-}
+}

interface/src/Util.h

@@ -74,7 +74,8 @@ void runTimingTests();
 
 float loadSetting(QSettings* settings, const char* name, float defaultValue);
 
-bool rayIntersectsSphere(glm::vec3& rayStarting, glm::vec3& rayNormalizedDirection, glm::vec3& sphereCenter, double sphereRadius);
+bool rayIntersectsSphere(const glm::vec3& rayStarting, const glm::vec3& rayNormalizedDirection,
+    const glm::vec3& sphereCenter, float sphereRadius, float& distance);
 
 bool pointInSphere(glm::vec3& point, glm::vec3& sphereCenter, double sphereRadius);
 

interface/src/avatar/Avatar.cpp

@@ -800,6 +800,21 @@ void Avatar::getBodyBallTransform(AvatarJointID jointID, glm::vec3& position, gl
     rotation = _bodyBall[jointID].rotation;
 }
 
+bool Avatar::findRayIntersection(const glm::vec3& origin, const glm::vec3& direction, float& distance) const {
+    float minDistance = FLT_MAX;
+    for (int i = 0; i < NUM_AVATAR_BODY_BALLS; i++) {
+        float distance;
+        if (rayIntersectsSphere(origin, direction, _bodyBall[i].position, _bodyBall[i].radius, distance)) {
+            minDistance = min(minDistance, distance);
+        }
+    }
+    if (minDistance == FLT_MAX) {
+        return false;
+    }
+    distance = minDistance;
+    return true;
+}
+
 int Avatar::parseData(unsigned char* sourceBuffer, int numBytes) {
     // change in position implies movement
     glm::vec3 oldPosition = _position;

interface/src/avatar/Avatar.h

@@ -164,6 +164,13 @@ public:
     // Get the position/rotation of a single body ball
     void getBodyBallTransform(AvatarJointID jointID, glm::vec3& position, glm::quat& rotation) const;
 
+    /// Checks for an intersection between the described ray and any of the avatar's body balls.
+    /// \param origin the origin of the ray
+    /// \param direction the unit direction vector
+    /// \param[out] distance the variable in which to store the distance to intersection
+    /// \return whether or not the ray intersected
+    bool findRayIntersection(const glm::vec3& origin, const glm::vec3& direction, float& distance) const;
+
     virtual int parseData(unsigned char* sourceBuffer, int numBytes);
 
     static void renderJointConnectingCone(glm::vec3 position1, glm::vec3 position2, float radius1, float radius2);