Touch & Drag problem

[NtcWai]

I coded follow the class TouchAndDragFragment:

public void moveSelectedObject(float x, float y) {
            if (mSelectedObject == null)
                return;

            //
            // -- unproject the screen coordinate (2D) to the camera's near plane
            //

            GLU.gluUnProject(x, getViewportHeight() - y, 0, mViewMatrix.getDoubleValues(), 0,
                mProjectionMatrix.getDoubleValues(), 0, mViewport, 0, mNearPos4, 0);

            //
            // -- unproject the screen coordinate (2D) to the camera's far plane
            //

            GLU.gluUnProject(x, getViewportHeight() - y, 1.f, mViewMatrix.getDoubleValues(), 0,
                    mProjectionMatrix.getDoubleValues(), 0, mViewport, 0, mFarPos4, 0);

            //
            // -- transform 4D coordinates (x, y, z, w) to 3D (x, y, z) by dividing
            // each coordinate (x, y, z) by w.
            //

            mNearPos.setAll(mNearPos4[0] / mNearPos4[3], mNearPos4[1]
                    / mNearPos4[3], mNearPos4[2] / mNearPos4[3]);
            mFarPos.setAll(mFarPos4[0] / mFarPos4[3],
                    mFarPos4[1] / mFarPos4[3], mFarPos4[2] / mFarPos4[3]);

            //
            // -- now get the coordinates for the selected object
            //

            double factor = (Math.abs(mSelectedObject.getZ()) + mNearPos.z)
                    / (getCurrentCamera().getFarPlane() - getCurrentCamera()
                            .getNearPlane());

            mNewObjPos.setAll(mFarPos);
            mNewObjPos.subtract(mNearPos);
            mNewObjPos.multiply(factor);
            mNewObjPos.add(mNearPos);

            mSelectedObject.setX(mNewObjPos.x);
            mSelectedObject.setY(mNewObjPos.y);
        }

and got an error like this.
I want to pick and drag object smoothly, but it immediately jumps to the touched position.

How to correct it ?
Thank for any help!

[Angie-Ie]

Hi @cuagia ,
I got same problem too, did you solve the problem?