truncation of struct initializers results in compiler warnings

[diablodale]

The codebase (including the precompiled Windows distribution headers) has initializers that are truncating their values. This results in compiler warnings. This and other such errors I've found #71 and #247 and #79 suggest the codebase has not been compiled with analyzers and warnings to surface easily found bugs.

Three incidents I found in my compile are double truncated to float. As they are initializers, I would hope (but it is not promised across all compilers) that the executable would only store a float in the static init data. But if the compiler does not, then the size is doubled (4 -> 8 bytes) and additional bytecode is needed to convert the double -> float at runtime.

Naturally, none of that is desired and the fix is easy. Put an f after the number literal.

// errant
float epsilon = 0.01;

// correct
float epsilon = 0.01f;

Setup

• all compilers and OS
• throughout codebase, yet can also be seen in the headers of precompiled Windows distrib: depthai-core-v2.11.1-win64

Repro

1. Enable warnings and errors in compiler. e.g. in MSVC it is with /W4
2. Compile an app that uses the depthai-core-v2.11.1-win64 and simple code that cascades to headers like RawFeatureTrackerConfig.hpp. Most any code, even just a dai device, will do this.

Result

...
[build] C:\repos-nobackup\depthai-core-v2.11.1-win64\include\depthai-shared/datatype/RawFeatureTrackerConfig.hpp(99): warning C4305: 'initializing': truncation from 'double' to 'float'
[build] C:\repos-nobackup\depthai-core-v2.11.1-win64\include\depthai-shared/datatype/RawFeatureTrackerConfig.hpp(105): warning C4305: 'initializing': truncation from 'double' to 'float'
[build] C:\repos-nobackup\depthai-core-v2.11.1-win64\include\depthai-shared/datatype/RawFeatureTrackerConfig.hpp(174): warning C4305: 'initializing': truncation from 'double' to 'float'
...

Expected

No warnings or errors. No increase in exe size, no runtime convert double->float.

[Luxonis-Brandon]

Thanks for the thorough report. Brought up internally. :-)

[diablodale]

Also found truncation in depthai SDK itself (I'm getting closer to a full depthai sdk compile)
Unclear if hard truncs on floats indicating dimensions is ok, or needs to round up, down, towards zero, accounting style, etc.

[diablodale]

@szabi-luxonis I have a PR for some of these if you don't yet have the work started. It needs changes in this repo and changes in depthai-shared.

[SzabolcsGergely]

@szabi-luxonis I have a PR for some of these if you don't yet have the work started. It needs changes in this repo and changes in depthai-shared.

Please do.
Once PR is in place I will update the firmware. (core and firmware must point to the same depthai-shared commit).

[diablodale]

@szabi-luxonis I have a PR ready. What is your team's standard approach for contributors wrt which branch/commit on which PRs should be?
For example, my changes to depthai-shared are currently branched from 99f9c588547e828663bb42e89f816d184d8dcff5 which is the submodule commit for v2.11.1.
Or should I rebase it on to the most recently commit of main and submit the PR that way?

[SzabolcsGergely]

@szabi-luxonis I have a PR ready. What is your team's standard approach for contributors wrt which branch/commit on which PRs should be? For example, my changes to depthai-shared are currently branched from 99f9c588547e828663bb42e89f816d184d8dcff5 which is the submodule commit for v2.11.1. Or should I rebase it on to the most recently commit of main and submit the PR that way?

Please target latest develop with PR.