function main_canvas_mousemove(e) {
    if (_drag_mode)
        if (_selected_obj) {
            m_app.disable_camera_controls();

            // calculate viewport coordinates
            var cam = m_scenes.get_active_camera();

            var x = m_mouse.get_coords_x(e);
            var y = m_mouse.get_coords_y(e);

            if (x >= 0 && y >= 0) {
                x -= _obj_delta_xy[0];
                y -= _obj_delta_xy[1];

                // emit ray from the camera
                var pline = m_cam.calc_ray(cam, x, y, _pline_tmp);

                // calculate ray/floor_plane intersection point
                var point = m_math.line_plane_intersect(FLOOR_PLANE_NORMAL, 0, pline, _vec3_tmp3);
                // console.log(point);
                if (!point)
                   console.log("no poit");

                // if (camera_ray[1] < 0)
                //    console.log("camera_ray[1] < 0");
                // do not process the parallel case and intersections behind the camera
                if (point) 
                    m_trans.set_translation_v(_selected_obj, point);
            }
        }
}