com.projecttango.examples.java.augmentedreality.AugmentedRealityActivity.java Source code

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Here is the source code for com.projecttango.examples.java.augmentedreality.AugmentedRealityActivity.java

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/*
 * Copyright 2016 Google Inc. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.projecttango.examples.java.augmentedreality;

import com.google.atap.tangoservice.Tango;
import com.google.atap.tangoservice.Tango.OnTangoUpdateListener;
import com.google.atap.tangoservice.TangoCameraIntrinsics;
import com.google.atap.tangoservice.TangoConfig;
import com.google.atap.tangoservice.TangoCoordinateFramePair;
import com.google.atap.tangoservice.TangoErrorException;
import com.google.atap.tangoservice.TangoEvent;
import com.google.atap.tangoservice.TangoInvalidException;
import com.google.atap.tangoservice.TangoOutOfDateException;
import com.google.atap.tangoservice.TangoPointCloudData;
import com.google.atap.tangoservice.TangoPoseData;
import com.google.atap.tangoservice.TangoXyzIjData;

import android.Manifest;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.pm.PackageManager;
import android.hardware.display.DisplayManager;
import android.opengl.GLSurfaceView;
import android.opengl.Matrix;
import android.os.Bundle;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.util.Log;
import android.view.Display;
import android.widget.Toast;

import org.rajawali3d.scene.ASceneFrameCallback;
import org.rajawali3d.view.SurfaceView;

import java.util.ArrayList;
import java.util.concurrent.atomic.AtomicBoolean;

import com.projecttango.tangosupport.TangoSupport;

/**
 * This is a simple example that shows how to use the Tango APIs to create an augmented reality (AR)
 * application. It displays the Planet Earth floating in space one meter in front of the device, and
 * the Moon rotating around it.
 * <p/>
 * This example uses Rajawali for the OpenGL rendering. This includes the color camera image in the
 * background and a 3D sphere with a texture of the Earth floating in space three meters forward.
 * This part is implemented in the {@code AugmentedRealityRenderer} class, like a regular Rajawali
 * application.
 * <p/>
 * This example focuses on how to use the Tango APIs to get the color camera data into an OpenGL
 * texture efficiently and have the OpenGL camera track the movement of the device in order to
 * achieve an augmented reality effect.
 * <p/>
 * Note that it is important to include the KEY_BOOLEAN_LOWLATENCYIMUINTEGRATION configuration
 * parameter in order to achieve best results synchronizing the Rajawali virtual world with the
 * RGB camera.
 * <p/>
 * If you're looking for a more stripped down example that doesn't use a rendering library like
 * Rajawali, see java_hello_video_example.
 */
public class AugmentedRealityActivity extends Activity {
    private static final String TAG = AugmentedRealityActivity.class.getSimpleName();
    private static final int INVALID_TEXTURE_ID = 0;

    private static final String CAMERA_PERMISSION = Manifest.permission.CAMERA;
    private static final int CAMERA_PERMISSION_CODE = 0;

    private SurfaceView mSurfaceView;
    private AugmentedRealityRenderer mRenderer;
    private Tango mTango;
    private TangoConfig mConfig;
    private boolean mIsConnected = false;
    private double mCameraPoseTimestamp = 0;

    // Texture rendering related fields.
    // NOTE: Naming indicates which thread is in charge of updating this variable.
    private int mConnectedTextureIdGlThread = INVALID_TEXTURE_ID;
    private AtomicBoolean mIsFrameAvailableTangoThread = new AtomicBoolean(false);
    private double mRgbTimestampGlThread;

    private int mDisplayRotation = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mSurfaceView = (SurfaceView) findViewById(R.id.surfaceview);
        mRenderer = new AugmentedRealityRenderer(this);

        DisplayManager displayManager = (DisplayManager) getSystemService(DISPLAY_SERVICE);
        if (displayManager != null) {
            displayManager.registerDisplayListener(new DisplayManager.DisplayListener() {
                @Override
                public void onDisplayAdded(int displayId) {
                }

                @Override
                public void onDisplayChanged(int displayId) {
                    synchronized (this) {
                        setDisplayRotation();
                    }
                }

                @Override
                public void onDisplayRemoved(int displayId) {
                }
            }, null);
        }

        setupRenderer();
    }

    @Override
    protected void onStart() {
        super.onStart();

        // Set render mode to RENDERMODE_CONTINUOUSLY to force getting onDraw callbacks until
        // the Tango service is properly set up and we start getting onFrameAvailable callbacks.
        mSurfaceView.setRenderMode(GLSurfaceView.RENDERMODE_CONTINUOUSLY);
        // Check and request camera permission at run time.
        if (checkAndRequestPermissions()) {
            bindTangoService();
        }
    }

    @Override
    public void onStop() {
        super.onStop();

        // Synchronize against disconnecting while the service is being used in the OpenGL thread or
        // in the UI thread.
        // NOTE: DO NOT lock against this same object in the Tango callback thread. Tango.disconnect
        // will block here until all Tango callback calls are finished. If you lock against this
        // object in a Tango callback thread it will cause a deadlock.
        synchronized (this) {
            try {
                mIsConnected = false;
                mTango.disconnectCamera(TangoCameraIntrinsics.TANGO_CAMERA_COLOR);
                // We need to invalidate the connected texture ID so that we cause a
                // re-connection in the OpenGL thread after resume.
                mConnectedTextureIdGlThread = INVALID_TEXTURE_ID;
                mTango.disconnect();
                mTango = null;
            } catch (TangoErrorException e) {
                Log.e(TAG, getString(R.string.exception_tango_error), e);
            }
        }
    }

    /**
     * Initialize Tango Service as a normal Android Service.
     */
    private void bindTangoService() {
        // Since we call mTango.disconnect() in onStop, this will unbind Tango Service, so every
        // time onStart gets called we should create a new Tango object.
        mTango = new Tango(AugmentedRealityActivity.this, new Runnable() {
            // Pass in a Runnable to be called from UI thread when Tango is ready. This Runnable
            // will be running on a new thread.
            // When Tango is ready, we can call Tango functions safely here only when there
            // are no UI thread changes involved.
            @Override
            public void run() {
                // Synchronize against disconnecting while the service is being used in the
                // OpenGL thread or in the UI thread.
                synchronized (AugmentedRealityActivity.this) {
                    try {
                        TangoSupport.initialize();
                        mConfig = setupTangoConfig(mTango);
                        mTango.connect(mConfig);
                        startupTango();
                        mIsConnected = true;
                        setDisplayRotation();
                    } catch (TangoOutOfDateException e) {
                        Log.e(TAG, getString(R.string.exception_out_of_date), e);
                        showsToastAndFinishOnUiThread(R.string.exception_out_of_date);
                    } catch (TangoErrorException e) {
                        Log.e(TAG, getString(R.string.exception_tango_error), e);
                        showsToastAndFinishOnUiThread(R.string.exception_tango_error);
                    } catch (TangoInvalidException e) {
                        Log.e(TAG, getString(R.string.exception_tango_invalid), e);
                        showsToastAndFinishOnUiThread(R.string.exception_tango_invalid);
                    }
                }
            }
        });
    }

    /**
     * Sets up the Tango configuration object. Make sure mTango object is initialized before
     * making this call.
     */
    private TangoConfig setupTangoConfig(Tango tango) {
        // Use default configuration for Tango Service, plus color camera, low latency
        // IMU integration and drift correction.
        TangoConfig config = tango.getConfig(TangoConfig.CONFIG_TYPE_DEFAULT);
        config.putBoolean(TangoConfig.KEY_BOOLEAN_COLORCAMERA, true);
        // NOTE: Low latency integration is necessary to achieve a precise alignment of
        // virtual objects with the RBG image and produce a good AR effect.
        config.putBoolean(TangoConfig.KEY_BOOLEAN_LOWLATENCYIMUINTEGRATION, true);
        // Drift correction allows motion tracking to recover after it loses tracking.
        // The drift-corrected pose is available through the frame pair with
        // base frame AREA_DESCRIPTION and target frame DEVICE.
        config.putBoolean(TangoConfig.KEY_BOOLEAN_DRIFT_CORRECTION, true);
        return config;
    }

    /**
     * Set up the callback listeners for the Tango Service and obtain other parameters required
     * after Tango connection.
     * Listen to updates from the RGB camera.
     */
    private void startupTango() {
        // No need to add any coordinate frame pairs since we aren't using pose data from callbacks.
        ArrayList<TangoCoordinateFramePair> framePairs = new ArrayList<TangoCoordinateFramePair>();

        mTango.connectListener(framePairs, new OnTangoUpdateListener() {
            @Override
            public void onPoseAvailable(TangoPoseData pose) {
                // We are not using onPoseAvailable for this app.
            }

            @Override
            public void onXyzIjAvailable(TangoXyzIjData xyzIj) {
                // We are not using onXyzIjAvailable for this app.
            }

            @Override
            public void onPointCloudAvailable(TangoPointCloudData pointCloud) {
                // We are not using onPointCloudAvailable for this app.
            }

            @Override
            public void onTangoEvent(TangoEvent event) {
                // We are not using onTangoEvent for this app.
            }

            @Override
            public void onFrameAvailable(int cameraId) {
                // Check if the frame available is for the camera we want and update its frame
                // on the view.
                if (cameraId == TangoCameraIntrinsics.TANGO_CAMERA_COLOR) {
                    // Now that we are receiving onFrameAvailable callbacks, we can switch
                    // to RENDERMODE_WHEN_DIRTY to drive the render loop from this callback.
                    // This will result in a frame rate of approximately 30FPS, in synchrony with
                    // the RGB camera driver.
                    // If you need to render at a higher rate (i.e., if you want to render complex
                    // animations smoothly) you  can use RENDERMODE_CONTINUOUSLY throughout the
                    // application lifecycle.
                    if (mSurfaceView.getRenderMode() != GLSurfaceView.RENDERMODE_WHEN_DIRTY) {
                        mSurfaceView.setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
                    }

                    // Mark a camera frame as available for rendering in the OpenGL thread.
                    mIsFrameAvailableTangoThread.set(true);
                    // Trigger a Rajawali render to update the scene with the new RGB data.
                    mSurfaceView.requestRender();
                }
            }
        });
    }

    /**
     * Connects the view and renderer to the color camara and callbacks.
     */
    private void setupRenderer() {
        // Register a Rajawali Scene Frame Callback to update the scene camera pose whenever a new
        // RGB frame is rendered.
        // (@see https://github.com/Rajawali/Rajawali/wiki/Scene-Frame-Callbacks)
        mRenderer.getCurrentScene().registerFrameCallback(new ASceneFrameCallback() {
            @Override
            public void onPreFrame(long sceneTime, double deltaTime) {
                // NOTE: This is called from the OpenGL render thread after all the renderer
                // onRender callbacks have a chance to run and before scene objects are rendered
                // into the scene.

                // Prevent concurrent access to {@code mIsFrameAvailableTangoThread} from the Tango
                // callback thread and service disconnection from an onPause event.
                try {
                    synchronized (AugmentedRealityActivity.this) {
                        // Don't execute tango API actions if we're not connected to the service.
                        if (!mIsConnected) {
                            return;
                        }

                        // Set up scene camera projection to match RGB camera intrinsics.
                        if (!mRenderer.isSceneCameraConfigured()) {
                            TangoCameraIntrinsics intrinsics = TangoSupport
                                    .getCameraIntrinsicsBasedOnDisplayRotation(
                                            TangoCameraIntrinsics.TANGO_CAMERA_COLOR, mDisplayRotation);
                            mRenderer.setProjectionMatrix(projectionMatrixFromCameraIntrinsics(intrinsics));
                        }
                        // Connect the camera texture to the OpenGL Texture if necessary
                        // NOTE: When the OpenGL context is recycled, Rajawali may regenerate the
                        // texture with a different ID.
                        if (mConnectedTextureIdGlThread != mRenderer.getTextureId()) {
                            mTango.connectTextureId(TangoCameraIntrinsics.TANGO_CAMERA_COLOR,
                                    mRenderer.getTextureId());
                            mConnectedTextureIdGlThread = mRenderer.getTextureId();
                            Log.d(TAG, "connected to texture id: " + mRenderer.getTextureId());
                        }

                        // If there is a new RGB camera frame available, update the texture
                        // with it.
                        if (mIsFrameAvailableTangoThread.compareAndSet(true, false)) {
                            mRgbTimestampGlThread = mTango.updateTexture(TangoCameraIntrinsics.TANGO_CAMERA_COLOR);
                        }

                        // If a new RGB frame has been rendered, update the camera pose to match.
                        if (mRgbTimestampGlThread > mCameraPoseTimestamp) {
                            // Calculate the camera color pose at the camera frame update time in
                            // OpenGL engine.
                            //
                            // When drift correction mode is enabled in config file, we must query
                            // the device with respect to Area Description pose in order to use the
                            // drift corrected pose.
                            //
                            // Note that if you don't want to use the drift corrected pose, the
                            // normal device with respect to start of service pose is available.
                            TangoPoseData lastFramePose = TangoSupport.getPoseAtTime(mRgbTimestampGlThread,
                                    TangoPoseData.COORDINATE_FRAME_AREA_DESCRIPTION,
                                    TangoPoseData.COORDINATE_FRAME_CAMERA_COLOR,
                                    TangoSupport.TANGO_SUPPORT_ENGINE_OPENGL,
                                    TangoSupport.TANGO_SUPPORT_ENGINE_OPENGL, mDisplayRotation);
                            if (lastFramePose.statusCode == TangoPoseData.POSE_VALID) {
                                // Update the camera pose from the renderer
                                mRenderer.updateRenderCameraPose(lastFramePose);
                                mCameraPoseTimestamp = lastFramePose.timestamp;
                            } else {
                                // When the pose status is not valid, it indicates the tracking has
                                // been lost. In this case, we simply stop rendering.
                                //
                                // This is also the place to display UI to suggest the user walk
                                // to recover tracking.
                                Log.w(TAG, "Can't get device pose at time: " + mRgbTimestampGlThread);
                            }
                        }
                    }

                    // Avoid crashing the application due to unhandled exceptions.
                } catch (TangoErrorException e) {
                    Log.e(TAG, "Tango API call error within the OpenGL render thread", e);
                } catch (Throwable t) {
                    Log.e(TAG, "Exception on the OpenGL thread", t);
                }
            }

            @Override
            public void onPreDraw(long sceneTime, double deltaTime) {

            }

            @Override
            public void onPostFrame(long sceneTime, double deltaTime) {

            }

            @Override
            public boolean callPreFrame() {
                return true;
            }
        });

        mSurfaceView.setSurfaceRenderer(mRenderer);
    }

    /**
     * Use Tango camera intrinsics to calculate the projection matrix for the Rajawali scene.
     *
     * @param intrinsics camera instrinsics for computing the project matrix.
     */
    private static float[] projectionMatrixFromCameraIntrinsics(TangoCameraIntrinsics intrinsics) {
        float cx = (float) intrinsics.cx;
        float cy = (float) intrinsics.cy;
        float width = (float) intrinsics.width;
        float height = (float) intrinsics.height;
        float fx = (float) intrinsics.fx;
        float fy = (float) intrinsics.fy;

        // Uses frustumM to create a projection matrix taking into account calibrated camera
        // intrinsic parameter.
        // Reference: http://ksimek.github.io/2013/06/03/calibrated_cameras_in_opengl/
        float near = 0.1f;
        float far = 100;

        float xScale = near / fx;
        float yScale = near / fy;
        float xOffset = (cx - (width / 2.0f)) * xScale;
        // Color camera's coordinates has y pointing downwards so we negate this term.
        float yOffset = -(cy - (height / 2.0f)) * yScale;

        float m[] = new float[16];
        Matrix.frustumM(m, 0, xScale * (float) -width / 2.0f - xOffset, xScale * (float) width / 2.0f - xOffset,
                yScale * (float) -height / 2.0f - yOffset, yScale * (float) height / 2.0f - yOffset, near, far);
        return m;
    }

    /**
     * Set the color camera background texture rotation and save the camera to display rotation.
     */
    private void setDisplayRotation() {
        Display display = getWindowManager().getDefaultDisplay();
        mDisplayRotation = display.getRotation();

        // We also need to update the camera texture UV coordinates. This must be run in the OpenGL
        // thread.
        mSurfaceView.queueEvent(new Runnable() {
            @Override
            public void run() {
                if (mIsConnected) {
                    mRenderer.updateColorCameraTextureUvGlThread(mDisplayRotation);
                }
            }
        });
    }

    /**
     * Check to see we have the necessary permissions for this app, and ask for them if we don't.
     *
     * @return True if we have the necessary permissions, false if we haven't.
     */
    private boolean checkAndRequestPermissions() {
        if (!hasCameraPermission()) {
            requestCameraPermission();
            return false;
        }
        return true;
    }

    /**
     * Check to see we have the necessary permissions for this app.
     */
    private boolean hasCameraPermission() {
        return ContextCompat.checkSelfPermission(this, CAMERA_PERMISSION) == PackageManager.PERMISSION_GRANTED;
    }

    /**
     * Request the necessary permissions for this app.
     */
    private void requestCameraPermission() {
        if (ActivityCompat.shouldShowRequestPermissionRationale(this, CAMERA_PERMISSION)) {
            showRequestPermissionRationale();
        } else {
            ActivityCompat.requestPermissions(this, new String[] { CAMERA_PERMISSION }, CAMERA_PERMISSION_CODE);
        }
    }

    /**
     * If the user has declined the permission before, we have to explain that the app needs this
     * permission.
     */
    private void showRequestPermissionRationale() {
        final AlertDialog dialog = new AlertDialog.Builder(this)
                .setMessage("Java Augmented Reality Example requires camera permission")
                .setPositiveButton("Ok", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialogInterface, int i) {
                        ActivityCompat.requestPermissions(AugmentedRealityActivity.this,
                                new String[] { CAMERA_PERMISSION }, CAMERA_PERMISSION_CODE);
                    }
                }).create();
        dialog.show();
    }

    /**
     * Result for requesting camera permission.
     */
    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
        if (hasCameraPermission()) {
            bindTangoService();
        } else {
            Toast.makeText(this, "Java Augmented Reality Example requires camera permission", Toast.LENGTH_LONG)
                    .show();
        }
    }

    /**
     * Display toast on UI thread.
     *
     * @param resId The resource id of the string resource to use. Can be formatted text.
     */
    private void showsToastAndFinishOnUiThread(final int resId) {
        runOnUiThread(new Runnable() {
            @Override
            public void run() {
                Toast.makeText(AugmentedRealityActivity.this, getString(resId), Toast.LENGTH_LONG).show();
                finish();
            }
        });
    }
}