obj_encoder functions produce invalid OBJ files when using a non-english numeric locale

[tim-depthkit]

I am using draco within my project as a library to enable exporting meshes directly to DRC, OBJ, PLY, etc.

If I set the program locale to the system default as follows:

setlocale(LC_ALL, ".UTF8");

and then I use the obj_encoder functions to save a mesh to an OBJ file, the result is unusable, as OBJ requires a . decimal separator, and the system default is set to a locale which uses ,.

I can get around this by adding another line to override the numeric locale:

setlocale(LC_NUMERIC, "en_US.UTF8");

However, I should not be required to do so, as this affects all floating point string conversions application wide.

[ondys]

I believe this should be fixed in the latest release, please give it a try.

[tim-depthkit]

This is still an issue in the latest release (1.5.7). I must still use the work around outlined above to ensure I get period decimal separators when my system is set to a region that uses a comma decimal separator.

Looking at the OBJ encoder code, I see the following in obj_encoder.cc

void ObjEncoder::EncodeFloat(float val) {
  // Use %F instead of %f to make the floating point non-locale aware.
  snprintf(num_buffer_, sizeof(num_buffer_), "%F", val);
  buffer()->Encode(num_buffer_, strlen(num_buffer_));
}

Both of these sources do not mention anything about the uppercase F vs lowercase f having anything to do with locale, but rather whether or not to print things like infinity or NAN in upper or lower case.