@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
Log.d(TAG, "surfaceChanged");
if (mHolder.getSurface() == null) {
Log.e(TAG, "Error: preview surface does not exist");
return;
}
// preview_width = width;
// preview_height = height;
mPreviewWidth = mCameraManager.getPreviewSize().x;
mPreviewHeight = mCameraManager.getPreviewSize().y;
mCameraManager.stopPreview();
mCameraManager.getCamera().setPreviewCallback(this);
mCameraManager.getCamera().setDisplayOrientation(90); // Portrait mode
mCameraManager.startPreview();
}
/**
* Transform result to surfaceView coordinates
*
* <p>This method is needed because coordinates are given in landscape camera coordinates. Now is
* working but transform operations aren't very explained
*
* <p>TODO re-write this method explaining each single value
*
* @return a new PointF array with transformed points
*/
private PointF[] transformToViewCoordinates(ResultPoint[] resultPoints) {
PointF[] transformedPoints = new PointF[resultPoints.length];
int index = 0;
if (resultPoints != null) {
float previewX = mCameraManager.getPreviewSize().x;
float previewY = mCameraManager.getPreviewSize().y;
float scaleX = this.getWidth() / previewY;
float scaleY = this.getHeight() / previewX;
for (ResultPoint point : resultPoints) {
PointF tmppoint = new PointF((previewY - point.getY()) * scaleX, point.getX() * scaleY);
transformedPoints[index] = tmppoint;
index++;
}
}
return transformedPoints;
}