Example usage for android.graphics Matrix setRectToRect

Introduction

In this page you can find the example usage for android.graphics Matrix setRectToRect.

Prototype

public boolean setRectToRect(RectF src, RectF dst, ScaleToFit stf)

Source Link

Document

Set the matrix to the scale and translate values that map the source rectangle to the destination rectangle, returning true if the the result can be represented.

Usage

From source file:com.ape.camera2raw.Camera2RawFragment.java

/**
 * Configure the necessary {@link Matrix} transformation to `mTextureView`,
 * and start/restart the preview capture session if necessary.
 * <p/>//w  w w .j  a v  a 2s. c o  m
 * This method should be called after the camera state has been initialized in
 * setUpCameraOutputs.
 *
 * @param viewWidth  The width of `mTextureView`
 * @param viewHeight The height of `mTextureView`
 */
private void configureTransform(int viewWidth, int viewHeight) {
    Activity activity = getActivity();
    synchronized (mCameraStateLock) {
        if (null == mTextureView || null == activity) {
            return;
        }

        StreamConfigurationMap map = mCharacteristics
                .get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP);

        // For still image captures, we always use the largest available size.
        Size largestJpeg = Collections.max(Arrays.asList(map.getOutputSizes(ImageFormat.JPEG)),
                new CompareSizesByArea());

        // Find the rotation of the device relative to the native device orientation.
        int deviceRotation = activity.getWindowManager().getDefaultDisplay().getRotation();
        Point displaySize = new Point();
        activity.getWindowManager().getDefaultDisplay().getSize(displaySize);

        // Find the rotation of the device relative to the camera sensor's orientation.
        int totalRotation = sensorToDeviceRotation(mCharacteristics, deviceRotation);

        // Swap the view dimensions for calculation as needed if they are rotated relative to
        // the sensor.
        boolean swappedDimensions = totalRotation == 90 || totalRotation == 270;
        int rotatedViewWidth = viewWidth;
        int rotatedViewHeight = viewHeight;
        int maxPreviewWidth = displaySize.x;
        int maxPreviewHeight = displaySize.y;

        if (swappedDimensions) {
            rotatedViewWidth = viewHeight;
            rotatedViewHeight = viewWidth;
            maxPreviewWidth = displaySize.y;
            maxPreviewHeight = displaySize.x;
        }

        // Preview should not be larger than display size and 1080p.
        if (maxPreviewWidth > MAX_PREVIEW_WIDTH) {
            maxPreviewWidth = MAX_PREVIEW_WIDTH;
        }

        if (maxPreviewHeight > MAX_PREVIEW_HEIGHT) {
            maxPreviewHeight = MAX_PREVIEW_HEIGHT;
        }

        // Find the best preview size for these view dimensions and configured JPEG size.
        Size previewSize = chooseOptimalSize(map.getOutputSizes(SurfaceTexture.class), rotatedViewWidth,
                rotatedViewHeight, maxPreviewWidth, maxPreviewHeight, largestJpeg);

        if (swappedDimensions) {
            mTextureView.setAspectRatio(previewSize.getHeight(), previewSize.getWidth());
        } else {
            mTextureView.setAspectRatio(previewSize.getWidth(), previewSize.getHeight());
        }

        // Find rotation of device in degrees (reverse device orientation for front-facing
        // cameras).
        int rotation = (mCharacteristics
                .get(CameraCharacteristics.LENS_FACING) == CameraCharacteristics.LENS_FACING_FRONT)
                        ? (360 + ORIENTATIONS.get(deviceRotation)) % 360
                        : (360 - ORIENTATIONS.get(deviceRotation)) % 360;

        Matrix matrix = new Matrix();
        RectF viewRect = new RectF(0, 0, viewWidth, viewHeight);
        RectF bufferRect = new RectF(0, 0, previewSize.getHeight(), previewSize.getWidth());
        float centerX = viewRect.centerX();
        float centerY = viewRect.centerY();

        // Initially, output stream images from the Camera2 API will be rotated to the native
        // device orientation from the sensor's orientation, and the TextureView will default to
        // scaling these buffers to fill it's view bounds.  If the aspect ratios and relative
        // orientations are correct, this is fine.
        //
        // However, if the device orientation has been rotated relative to its native
        // orientation so that the TextureView's dimensions are swapped relative to the
        // native device orientation, we must do the following to ensure the output stream
        // images are not incorrectly scaled by the TextureView:
        //   - Undo the scale-to-fill from the output buffer's dimensions (i.e. its dimensions
        //     in the native device orientation) to the TextureView's dimension.
        //   - Apply a scale-to-fill from the output buffer's rotated dimensions
        //     (i.e. its dimensions in the current device orientation) to the TextureView's
        //     dimensions.
        //   - Apply the rotation from the native device orientation to the current device
        //     rotation.
        if (Surface.ROTATION_90 == deviceRotation || Surface.ROTATION_270 == deviceRotation) {
            bufferRect.offset(centerX - bufferRect.centerX(), centerY - bufferRect.centerY());
            matrix.setRectToRect(viewRect, bufferRect, Matrix.ScaleToFit.FILL);
            float scale = Math.max((float) viewHeight / previewSize.getHeight(),
                    (float) viewWidth / previewSize.getWidth());
            matrix.postScale(scale, scale, centerX, centerY);

        }
        matrix.postRotate(rotation, centerX, centerY);

        mTextureView.setTransform(matrix);

        // Start or restart the active capture session if the preview was initialized or
        // if its aspect ratio changed significantly.
        if (mPreviewSize == null || !checkAspectsEqual(previewSize, mPreviewSize)) {
            mPreviewSize = previewSize;
            if (mState != STATE_CLOSED) {
                createCameraPreviewSessionLocked();
            }
        }
    }
}