package cgeo.geocaching.utils;
import android.content.Context;
import android.view.Surface;
import android.view.WindowManager;
import cgeo.geocaching.CgeoApplication;
public final class AngleUtils {
private static class WindowManagerHolder {
public static final WindowManager WINDOW_MANAGER = (WindowManager) CgeoApplication.getInstance().getSystemService(Context.WINDOW_SERVICE);
}
private AngleUtils() {
// Do not instantiate
}
/**
* Return the angle to turn of to go from an angle to the other
*
* @param from
* the origin angle in degrees
* @param to
* the target angle in degrees
* @return a value in degrees, in the [-180, 180[ range
*/
public static float difference(final float from, final float to) {
return normalize(to - from + 180) - 180;
}
/**
* Normalize an angle so that it belongs to the [0, 360[ range.
* @param angle the angle in degrees
* @return the same angle in the [0, 360[ range
*/
public static float normalize(final float angle) {
final float mod = angle % 360;
return mod >= 0 ? mod : (mod + 360) % 360;
}
public static int getRotationOffset() {
switch (WindowManagerHolder.WINDOW_MANAGER.getDefaultDisplay().getRotation()) {
case Surface.ROTATION_0:
return 0;
case Surface.ROTATION_90:
return 90;
case Surface.ROTATION_180:
return 180;
case Surface.ROTATION_270:
return 270;
default:
return 0;
}
}
/**
* Take the phone rotation (through a given activity) in account and adjust the direction.
*
* @param direction the unadjusted direction in degrees, in the [0, 360[ range
* @return the adjusted direction in degrees, in the [0, 360[ range
*/
public static float getDirectionNow(final float direction) {
return normalize(direction + getRotationOffset());
}
/**
* Reverse the phone rotation (through a given activity) in account and adjust the direction.
*
* @param direction the unadjusted direction in degrees, in the [0, 360[ range
* @return the adjusted direction in degrees, in the [0, 360[ range
*/
public static float reverseDirectionNow(final float direction) {
return normalize(direction - getRotationOffset());
}
}