Shuo SUN

Results 2 issues of Shuo SUN

Hi, I experienced a dependency issue while running the `object_tracker.py`, the `cvShowImage` function seems to have an error in openCV 3.4.2 ``` cv2.error: OpenCV(3.4.2) /tmp/build/80754af9/opencv-suite_1535558553474/work/modules/highgui/src/window.cpp:632: error: (-2:Unspecified error) The function...

# Fixed the behavior of the function `plot_simulator_state()` when the parameter `center_agent_idx` in `viz_config` is not `-1 # sdc`. ## Original Issue When the parameter `center_agent_idx` in `viz_config` is set...