Update references based on merge

app/src/main/java/de/trac/spherical/MainActivity.java

@@ -85,7 +85,7 @@ public class MainActivity extends AppCompatActivity {
         fab.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
-                PhotoSphereSurfaceView.USE_TOUCH = !PhotoSphereSurfaceView.USE_TOUCH;
+                sphereFragment.toggleUseTouchInput();
                 displayUI(false);
             }
         });

app/src/main/java/de/trac/spherical/SphereFragment.java

@@ -75,4 +75,8 @@ public class SphereFragment extends ImageFragment implements View.OnTouchListene
         }
         surfaceView.setBitmap(bitmap);
     }
+
+    public void toggleUseTouchInput() {
+        surfaceView.setUseTouchInput(!surfaceView.getUseTouchInput());
+    }
 }

app/src/main/java/de/trac/spherical/parser/PhotoSphereParser.java

@@ -94,6 +94,11 @@ public class PhotoSphereParser {
         throwIfUnexpectedEOF(i, r.length);
         int exifLen = integer(r);
 
+        //Check for broken or unavailable header
+        if (exifLen <= 1) {
+            return null;
+        }
+
         //Skip EXIF header
         r = new byte[exifLen - 2];
         i = inputStream.read(r);

app/src/main/java/de/trac/spherical/rendering/PhotoSphereSurfaceView.java

@@ -16,15 +16,22 @@ import android.view.MotionEvent;
  */
 public class PhotoSphereSurfaceView extends GLSurfaceView implements SensorEventListener {
 
-    public static boolean USE_TOUCH = false; // TODO: determine dynamically
+    // Decision variable for either using touch or device rotation input.
+    private boolean useTouchInput = false;
 
     // The actual rotation matrix determined by user input.
     private final float rotationMatrix [] = new float[16];
 
+    // The temporary rotation delta matrix.
+    private final float tempMatrix [] = new float[16];
+
     // These vectors Are used for ray determination.
     private final float rayStart [] = new float[4];
     private final float rayDirection [] = new float[4];
 
+    //
+    float oldAngleXZ, oldAngleY;
+
     // The renderer used by this view.
     private PhotoSphereRenderer renderer;
 
@@ -55,12 +62,9 @@ public class PhotoSphereSurfaceView extends GLSurfaceView implements SensorEvent
     @Override
     public boolean onTouchEvent(MotionEvent event) {
 
-        if(!USE_TOUCH)
+        if(!useTouchInput)
             return true;
 
-        switch (event.getAction()) {
-            case MotionEvent.ACTION_MOVE:
-
         // Retrieve ray in world space.
         renderer.getRay(event.getX(), event.getY(), rayStart, rayDirection);
 
@@ -87,15 +91,32 @@ public class PhotoSphereSurfaceView extends GLSurfaceView implements SensorEvent
         float py = rayStart[1] + t*rayDirection[1];
         float pz = rayStart[2] + t*rayDirection[2];
 
+        synchronized (rotationMatrix) {
+            Matrix.translateM(rotationMatrix, 0, px, py, pz);
+        }
+
+        /*
         // Calculate angles.
-                //float angleX = (float) Math.toDegrees(Math.atan2(py, px));
+        float angleY = (float) Math.toDegrees(Math.atan2(pz, px));
-                //float angleY = (float) Math.toDegrees(Math.acos(pz/Matrix.length(px, py, pz)));
+        float angleXZ = (float) Math.toDegrees(Math.acos(py));
+
+        switch (event.getAction()) {
+            case MotionEvent.ACTION_DOWN:
+                oldAngleY = angleY;
+                oldAngleXZ = angleXZ;
+                System.arraycopy(getRotationMatrix(), 0, tempMatrix, 0, 16);
+                break;
+            case MotionEvent.ACTION_MOVE:
 
                 synchronized (rotationMatrix) {
-                    Matrix.setLookAtM(rotationMatrix, 0, 0.0f, 0.0f, 0.0f, px, py, pz, 1.0f, 0.0f, 0.0f);
+                    System.arraycopy(tempMatrix, 0, rotationMatrix, 0, 16);
+                    //Matrix.rotateM(rotationMatrix, 0, oldAngleY-angleY, 0.0f, 1.0f, 0.0f);
+                    Matrix.rotateM(rotationMatrix, 0, oldAngleXZ-angleXZ, 1.0f, 0.0f, 0.0f);
+                    //Matrix.setLookAtM(rotationMatrix, 0, 0.0f, 0.0f, 0.0f, px, py, pz, 1.0f, 0.0f, 0.0f);
                 }
+                break;
         }
-
+        */
         return true;
     }
 
@@ -107,7 +128,7 @@ public class PhotoSphereSurfaceView extends GLSurfaceView implements SensorEvent
     @Override
     public void onSensorChanged(SensorEvent event) {
 
-        if(USE_TOUCH)
+        if(useTouchInput)
             return;
 
         synchronized (rotationMatrix) {
@@ -133,4 +154,20 @@ public class PhotoSphereSurfaceView extends GLSurfaceView implements SensorEvent
     public void setBitmap(Bitmap bitmap) {
         renderer.requestBitmapUpload(bitmap);
     }
+
+    /**
+     * Sets input to be used for transformation calculation.
+     * @param useTouchInput true, if touch input should be used
+     */
+    public void setUseTouchInput(boolean useTouchInput) {
+        this.useTouchInput = useTouchInput;
+    }
+
+    /**
+     * Returns if touch input is used for transformation calculations.
+     * @return true, if touch input is used, false
+     */
+    public boolean getUseTouchInput() {
+        return useTouchInput;
+    }
 }