Added simulated head-tracking on VR simulator

A simple 1st person camera... still requires some work...

src/raylib.h

@@ -891,6 +891,7 @@ RLAPI void DestroyLight(Light light);                                     // Des
 RLAPI void InitVrDevice(int vdDevice);            // Init VR device
 RLAPI void CloseVrDevice(void);                   // Close VR device
 RLAPI bool IsVrDeviceReady(void);                 // Detect if VR device (or simulator) is ready
+RLAPI bool IsVrSimulator(void);                   // Detect if VR simulator is running
 RLAPI void UpdateVrTracking(void);                // Update VR tracking (position and orientation)
 RLAPI void ToggleVrMode(void);                    // Enable/Disable VR experience (device or simulator)
 

src/rlgl.c

@@ -2710,6 +2710,12 @@ bool IsVrDeviceReady(void)
     return (vrDeviceReady || vrSimulator) && vrEnabled;
 }
 
+// Detect if VR simulator is running
+bool IsVrSimulator(void)
+{
+    return vrSimulator;
+}
+
 // Enable/Disable VR experience (device or simulator)
 void ToggleVrMode(void)
 {