Add access to camera properties POJO

Currently the only properties in interest (to me at least) are the vertical
and horizontal view angles to allow for better AR mode.

camerakit/src/main/api16/com/flurgle/camerakit/Camera1.java

@@ -6,6 +6,7 @@ import android.hardware.Camera;
 import android.media.CamcorderProfile;
 import android.media.MediaRecorder;
 import android.os.Handler;
+import android.support.annotation.Nullable;
 import android.view.MotionEvent;
 import android.view.SurfaceHolder;
 import android.view.View;
@@ -36,6 +37,7 @@ public class Camera1 extends CameraImpl {
     private int mCameraId;
     private Camera mCamera;
     private Camera.Parameters mCameraParameters;
+    private CameraProperties mCameraProperties;
     private Camera.CameraInfo mCameraInfo;
     private Size mPreviewSize;
     private Size mCaptureSize;
@@ -309,6 +311,12 @@ public class Camera1 extends CameraImpl {
         return mCamera != null;
     }
 
+    @Nullable
+    @Override
+    CameraProperties getCameraProperties() {
+        return mCameraProperties;
+    }
+
     // Internal:
 
     private void openCamera() {
@@ -319,6 +327,7 @@ public class Camera1 extends CameraImpl {
         mCamera = Camera.open(mCameraId);
         mCameraParameters = mCamera.getParameters();
 
+        collectCameraProperties();
         adjustCameraParameters();
         mCamera.setDisplayOrientation(calculatePreviewRotation());
 
@@ -391,6 +400,11 @@ public class Camera1 extends CameraImpl {
         mCamera.setParameters(mCameraParameters);
     }
 
+    private void collectCameraProperties() {
+        mCameraProperties = new CameraProperties(mCameraParameters.getVerticalViewAngle(),
+                mCameraParameters.getHorizontalViewAngle());
+    }
+
     private TreeSet<AspectRatio> findCommonAspectRatios(List<Camera.Size> previewSizes, List<Camera.Size> captureSizes) {
         Set<AspectRatio> previewAspectRatios = new HashSet<>();
         for (Camera.Size size : previewSizes) {

camerakit/src/main/api21/com/flurgle/camerakit/Camera2.java

@@ -3,14 +3,18 @@ package com.flurgle.camerakit;
 import android.annotation.TargetApi;
 import android.content.Context;
 import android.graphics.ImageFormat;
+import android.graphics.PointF;
 import android.hardware.camera2.CameraAccessException;
 import android.hardware.camera2.CameraCharacteristics;
 import android.hardware.camera2.CameraDevice;
 import android.hardware.camera2.CameraManager;
 import android.hardware.camera2.params.StreamConfigurationMap;
+import android.support.annotation.Nullable;
 import android.util.Log;
+import android.util.SizeF;
 
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.TreeSet;
@@ -28,6 +32,8 @@ class Camera2 extends CameraImpl {
     private Size mCaptureSize;
     private Size mPreviewSize;
 
+    private final HashMap<String, CameraProperties> mCameraPropertyMap = new HashMap<>();
+
     Camera2(CameraListener callback, PreviewImpl preview, Context context) {
         super(callback, preview);
         preview.setCallback(new PreviewImpl.Callback() {
@@ -38,6 +44,36 @@ class Camera2 extends CameraImpl {
         });
 
         mCameraManager = (CameraManager) context.getSystemService(Context.CAMERA_SERVICE);
+
+        // Get all view angles
+        try {
+            for (final String cameraId : mCameraManager.getCameraIdList()) {
+                CameraCharacteristics characteristics =
+                        mCameraManager.getCameraCharacteristics(cameraId);
+                @SuppressWarnings("ConstantConditions")
+                int orientation = characteristics.get(CameraCharacteristics.LENS_FACING);
+                if (orientation == CameraCharacteristics.LENS_FACING_BACK) {
+                    float[] maxFocus = characteristics.get(
+                            CameraCharacteristics.LENS_INFO_AVAILABLE_FOCAL_LENGTHS);
+                    if (maxFocus == null) {
+                        continue;
+                    }
+                    SizeF size = characteristics.get(
+                            CameraCharacteristics.SENSOR_INFO_PHYSICAL_SIZE);
+                    if (size == null) {
+                        continue;
+                    }
+                    float w = size.getWidth();
+                    float h = size.getHeight();
+                    mCameraPropertyMap.put(cameraId, new CameraProperties(
+                            (float) Math.toDegrees(2*Math.atan(size.getWidth()/(maxFocus[0]*2))),
+                            (float) Math.toDegrees(2*Math.atan(size.getHeight()/(maxFocus[0]*2)))
+                    ));
+                }
+            }
+        } catch (CameraAccessException e) {
+            throw new RuntimeException("Failed to get camera view angles", e);
+        }
     }
 
     // CameraImpl:
@@ -196,6 +232,14 @@ class Camera2 extends CameraImpl {
         return mCamera != null;
     }
 
+    @Nullable
+    @Override
+    CameraProperties getCameraProperties() {
+        if (mCamera == null) {
+            return null;
+        }
+        return mCameraPropertyMap.get(mCamera.getId());
+    }
     // Internal
 
     private List<Size> getAvailableCaptureResolutions() {

camerakit/src/main/base/com/flurgle/camerakit/CameraImpl.java

@@ -1,5 +1,7 @@
 package com.flurgle.camerakit;
 
+import android.support.annotation.Nullable;
+
 abstract class CameraImpl {
 
     protected final CameraListener mCameraListener;
@@ -30,4 +32,7 @@ abstract class CameraImpl {
     abstract Size getPreviewResolution();
     abstract boolean isCameraOpened();
 
+    @Nullable
+    abstract CameraProperties getCameraProperties();
+
 }

camerakit/src/main/base/com/flurgle/camerakit/CameraProperties.java

@@ -0,0 +1,14 @@
+package com.flurgle.camerakit;
+
+/**
+ * Simple pojo containing various camera properties.
+ */
+public class CameraProperties {
+    public final float verticalViewingAngle;
+    public final float horizontalViewingAngle;
+
+    public CameraProperties(float verticalViewingAngle, float horizontalViewingAngle) {
+        this.verticalViewingAngle = verticalViewingAngle;
+        this.horizontalViewingAngle = horizontalViewingAngle;
+    }
+}

camerakit/src/main/java/com/flurgle/camerakit/CameraView.java

@@ -258,6 +258,11 @@ public class CameraView extends FrameLayout {
         mCameraImpl.stop();
     }
 
+    @Nullable
+    public CameraProperties getCameraProperties() {
+        return mCameraImpl.getCameraProperties();
+    }
+
     @Facing
     public int getFacing() {
         return mFacing;