Example usage for android.graphics Matrix setRotate

List of usage examples for android.graphics Matrix setRotate

Introduction

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

Prototype

public void setRotate(float degrees, float px, float py) 

Source Link

Document

Set the matrix to rotate by the specified number of degrees, with a pivot point at (px, py).

Usage

From source file:uk.org.rivernile.edinburghbustracker.android.fragments.general.BusStopDetailsFragment.java

/**
 * Update the direction needle so that it is pointing towards the bus stop,
 * based on the device location and the direction it is facing.
 *///  ww  w.  j  ava2  s  .  c o m
private void updateDirectionNeedle() {
    // We need values for location, the accelerometer and magnetometer to
    // continue.
    if (lastLocation == null || accelerometerValues == null || magnetometerValues == null) {
        // Make sure the needle isn't showing.
        txtDistance.setCompoundDrawablesWithIntrinsicBounds(null, null, null, null);
        recycleNeedleBitmapIfNotNull(null);

        return;
    }

    // Calculating the rotation matrix may fail, for example, if the device
    // is in freefall. In that case we cannot continue as the values will
    // be unreliable.
    if (!SensorManager.getRotationMatrix(rotationMatrix, null, accelerometerValues, magnetometerValues)) {
        return;
    }

    // The screen rotation was obtained earlier.
    switch (screenRotation) {
    // There's lots of information about this elsewhere, but briefly;
    // The values from the sensors are in the device's coordinate system
    // which may be correct if the device is in its natural orientation,
    // but it needs to be remapped if the device is rotated.
    case Surface.ROTATION_0:
        SensorManager.remapCoordinateSystem(rotationMatrix, SensorManager.AXIS_X, SensorManager.AXIS_Z,
                rotationMatrix);
        break;
    case Surface.ROTATION_90:
        SensorManager.remapCoordinateSystem(rotationMatrix, SensorManager.AXIS_Z, SensorManager.AXIS_MINUS_X,
                rotationMatrix);
        break;
    case Surface.ROTATION_180:
        SensorManager.remapCoordinateSystem(rotationMatrix, SensorManager.AXIS_MINUS_X,
                SensorManager.AXIS_MINUS_Z, rotationMatrix);
        break;
    case Surface.ROTATION_270:
        SensorManager.remapCoordinateSystem(rotationMatrix, SensorManager.AXIS_MINUS_Z, SensorManager.AXIS_X,
                rotationMatrix);
        break;
    }

    // Get the X, Y and Z orientations, which are in radians. Covert this
    // in to degrees East of North.
    SensorManager.getOrientation(rotationMatrix, headings);
    double heading = Math.toDegrees(headings[0]);

    // If there's a GeomagneticField value, then adjust the heading to take
    // this in to account.
    if (geoField != null) {
        heading -= geoField.getDeclination();
    }

    // The orientation is in the range of -180 to +180. Convert this in to
    // a range of 0 to 360.
    final float bearingTo = distance[1] < 0 ? distance[1] + 360 : distance[1];

    // This is the heading to the bus stop.
    heading = bearingTo - heading;

    // The above calculation may come out as a negative number again. Put
    // this back in to the range of 0 to 360.
    if (heading < 0) {
        heading += 360;
    }

    // This 'if' statement is required to prevent a crash during device
    // rotation. It ensured that the Fragment is still part of the Activity.
    if (isAdded()) {
        // Get the arrow bitmap from the resources.
        final Bitmap needleIn = BitmapFactory.decodeResource(getResources(), R.drawable.heading_arrow);
        // Get an identity matrix and rotate it by the required amount.
        final Matrix m = new Matrix();
        m.setRotate((float) heading % 360, (float) needleIn.getWidth() / 2, (float) needleIn.getHeight() / 2);
        // Apply the rotation matrix to the Bitmap, to create a new Bitmap.
        final Bitmap needleOut = Bitmap.createBitmap(needleIn, 0, 0, needleIn.getWidth(), needleIn.getHeight(),
                m, true);

        // Recycle the needle read in if it's not the same as the rotated
        // needle.
        if (needleIn != needleOut) {
            needleIn.recycle();
        }

        // This Bitmap needs to be converted to a Drawable type.
        final BitmapDrawable drawable = new BitmapDrawable(getResources(), needleOut);
        // Set the new needle to be on the right hand side of the TextView.
        txtDistance.setCompoundDrawablesWithIntrinsicBounds(null, null, drawable, null);
        recycleNeedleBitmapIfNotNull(needleOut);
    } else {
        // If the Fragment is not added to the Activity, then make sure
        // there's no needle.
        txtDistance.setCompoundDrawablesWithIntrinsicBounds(null, null, null, null);
        recycleNeedleBitmapIfNotNull(null);
    }
}

From source file:com.kjsaw.alcosys.ibacapp.IBAC.java

private Bitmap processBitmap(Bitmap orginalBitmap, int degrees) {
    Matrix matrixRotate = new Matrix();
    matrixRotate.setRotate(degrees, (float) orginalBitmap.getWidth() / 2,
            (float) orginalBitmap.getHeight() / 2);
    Bitmap rotatedBitmap = Bitmap.createBitmap(orginalBitmap, 0, 0, orginalBitmap.getWidth(),
            orginalBitmap.getHeight(), matrixRotate, true);

    int width = rotatedBitmap.getWidth();
    int height = rotatedBitmap.getHeight();

    int newWidth = 240;
    int newHeight = 320;

    float scaleWidth = ((float) newWidth) / width;
    float scaleHeight = ((float) newHeight) / height;

    Matrix matrixResize = new Matrix();
    if (Session.isFacingCamera) {
        matrixResize.setScale(-1, 1);// reversal
    }/*from   www  .  j  ava  2  s. c om*/
    matrixResize.postScale(scaleWidth, scaleHeight);

    return Bitmap.createBitmap(rotatedBitmap, 0, 0, width, height, matrixResize, true);
}