Voxel hashing GUI

[theNded]

This PR introduces the VoxelHashing's application. Depending on #3323.

To be fixed before merging:

• 2nd checkbox bug
• Camera intrinsic's path and dataset file structure

Features:

• Real-time RGB-D tracking and reconstruction (~40Hz on GPU and ~5Hz on CPU)
• Interactive parameter selection
• Point cloud and trajectory output at exit

TBD in the future:

• Support streaming in/out GPU to enable larger scale reconstruction with a lower GPU budget
• More robust tracking
• File manager for customized input/output in the UI
  

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This change is 

[update-docs]

Thanks for submitting this pull request! The maintainers of this repository would appreciate if you could update the CHANGELOG.md based on your changes.

[errissa]

Reviewed 27 of 28 files at r1.
Reviewable status: 27 of 28 files reviewed, 4 unresolved discussions (waiting on @prewettg, @reyanshsolis, and @theNded)

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examples/cpp/VoxelHashingGUI.cpp, line 14 at r1 (raw file):

static const Eigen::Vector3d kTangoSkyBlueDark(0.125, 0.290, 0.529);

std::shared_ptr<geometry::LineSet> CreateCameraFrustum(

Most of this function could be replaced with LineSet::CreateCameraVisualization

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examples/cpp/VoxelHashingGUI.cpp, line 774 at r1 (raw file):

int main(int argc, char** argv) {
    if (argc < 2) {
        utility::LogError("Expected a dataset path as input.");

This should print a usage message and quit (return) gracefully.

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examples/cpp/VoxelHashingGUI.cpp, line 779 at r1 (raw file):

    std::string dataset_path = argv[1];
    if (!utility::filesystem::DirectoryExists(dataset_path)) {
        utility::LogError("Expected an existing directory {}", dataset_path);

LogError throws an exception that is uncaught which results in a crash. Since this is an expected possible error condition and we are in main I don't think it should crash the program. I recommend using LogWarning plus a return -1 or some other return value.

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examples/cpp/VoxelHashingGUI.cpp, line 787 at r1 (raw file):

            utility::GetProgramOptionAsString(argc, argv, "--device", "CUDA:0");
    if (device != "CPU:0" && device != "CUDA:0") {
        utility::LogError("Unrecognized device {}. Expecting CPU:0 or CUDA:0.",

Please see previous comment.

[errissa]

Reviewed 1 of 28 files at r1.
Reviewable status: all files reviewed, 4 unresolved discussions (waiting on @prewettg, @reyanshsolis, and @theNded)

[theNded]

Reviewable status: 23 of 30 files reviewed, 4 unresolved discussions (waiting on @errissa, @prewettg, and @reyanshsolis)

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examples/cpp/VoxelHashingGUI.cpp, line 14 at r1 (raw file):

Previously, errissa (Rene) wrote…

Most of this function could be replaced with LineSet::CreateCameraVisualization

Done.

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examples/cpp/VoxelHashingGUI.cpp, line 774 at r1 (raw file):

Previously, errissa (Rene) wrote…

This should print a usage message and quit (return) gracefully.

Done.

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examples/cpp/VoxelHashingGUI.cpp, line 779 at r1 (raw file):

Previously, errissa (Rene) wrote…

LogError throws an exception that is uncaught which results in a crash. Since this is an expected possible error condition and we are in main I don't think it should crash the program. I recommend using LogWarning plus a return -1 or some other return value.

Done.

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examples/cpp/VoxelHashingGUI.cpp, line 787 at r1 (raw file):

Previously, errissa (Rene) wrote…

Please see previous comment.

Done.

[errissa]

Reviewed 7 of 7 files at r2.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @prewettg and @reyanshsolis)