This is the third PR in a series of changes that aim to make building with the visualizer module optional and remove the cv::viz dependency from other modules. A key feature of this change is to utilize abstract classes to add dummy visualizer classes with stubbed out functions. These dummy classes can then be utilized when building without the visualizer. This change focuses on adding the BaseOpenCvVisualizer abstract class and updating OpenCvVisualizer3D to be derived from it. This class is used by MeshOptimization and EurocPlayground. The dummy class is not yet included, to simplify the PR.

Changes include:

• Adding BaseOpenCvVisualizer3D abstract class
• Updating OpenCvVisualizer3D to override relevant functions and be derived from abstract class
• Updating all non-visualizer classes using OpenCvVisualizer3D to reference the abstract class instead.

The follow up PR will have all other abstract classes, but submitting this one first to make sure the format of changes are reasonable.

Full design document can be found here.
Visualization Build Option Refactor for Kimera-VIO.pdf

Testing process
Build docker container for testing

• Navigate to Kimera-VIO/scripts/Docker
• Modify the Dockerfile to get the relevant testing branch instead of master. Change line 85 to the following:

RUN git clone https://github.com/Virtana/Kimera-VIO.git && git checkout origin/<branch_name>

• Build and run the image:

./kimera_vio_docker.bash

Testing

1. Update Kimera-VIO to generate logs:
   1. For stereo: Open Kimera-VIO/params/Euroc/flags/stereoVIOEuroc.flags with your editor of choice and modify -- log_output to true.
   2. For mono:
      1. Open Kimera-VIO/params/EurocMono/flags/stereoVIOEuroc.flags and modify -- log_output to true.
      2. Open Kimera-VIO/params/EurocMono/BackendParams.yaml with the following changes:
         • linearizationMode: 1
      3. Open Kimera-VIO/params/EurocMono/FrontendParams.yaml with the following changes:
         • maxFeatureAge: 15
         • feature_detector_type: 0
         • maxFeaturesPerFrame: 200
      4. Open Kimera-VIO/script/stereoVIOEuroc.bash and change the LOG_OUTPUT variable from 0 to 1.
2. Run Kimera-VIO: ./stereoVIOEuroc.bash.
3. You can examine output logs in Kimera-VIO/output_logs/ to ensure the values in traj_gt.csv are the same as the version on master. You can re-run after checking out to master and rebuilding and installing:

git checkout master
rm -r build && mkdir build
cd build
cmake .. && make -j4 install

Then re-run Kimera-VIO as shown in step 2. You should be re-running with the same configuration options.

You should also be looking out for any differences in the visualizer behaviour.