upgrade embree to v4.3.3 and fix fmt formatter for RTCError

[daizhirui]

This pull request fixes the following build error:

Open3D/cpp/open3d/t/geometry/RaycastingScene.cpp:1184:9: error: enumeration value ‘RTC_ERROR_LEVEL_ZERO_RAYTRACING_SUPPORT_MISSING’ not handled in switch [-Werror=switch]
 1184 |         switch (c) {
      |         ^~~~~~
cc1plus: all warnings being treated as errors

[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.

[timohl]

Failed with:
/root/Open3D/cpp/open3d/t/geometry/RaycastingScene.cpp:1206:18: error: 'RTC_ERROR_LEVEL_ZERO_RAYTRACING_SUPPORT_MISSING' was not declared in this scope

Did you build with another version of embree?

enum RTCError does not contain that value in my Ubuntu build of main at home :
(build/embree/src/ext_embree/include/embree4/rtcore_device.h:L79-L88)

enum RTCError
{
  RTC_ERROR_NONE              = 0,
  RTC_ERROR_UNKNOWN           = 1,
  RTC_ERROR_INVALID_ARGUMENT  = 2,
  RTC_ERROR_INVALID_OPERATION = 3,
  RTC_ERROR_OUT_OF_MEMORY     = 4,
  RTC_ERROR_UNSUPPORTED_CPU   = 5,
  RTC_ERROR_CANCELLED         = 6,
};

[timohl]

Latest embree does contain the value though, so might be good when embree is upgraded:
https://github.com/RenderKit/embree/blob/3c9936cb6bfb21c572503438d7a10a432e885d2c/include/embree4/rtcore_device.h#L82-L92

enum RTCError
{
  RTC_ERROR_NONE                                  = 0,
  RTC_ERROR_UNKNOWN                               = 1,
  RTC_ERROR_INVALID_ARGUMENT                      = 2,
  RTC_ERROR_INVALID_OPERATION                     = 3,
  RTC_ERROR_OUT_OF_MEMORY                         = 4,
  RTC_ERROR_UNSUPPORTED_CPU                       = 5,
  RTC_ERROR_CANCELLED                             = 6,
  RTC_ERROR_LEVEL_ZERO_RAYTRACING_SUPPORT_MISSING = 7,
};

Edit:
Maybe this function would be better instead of switch case:
https://github.com/RenderKit/embree/blob/3c9936cb6bfb21c572503438d7a10a432e885d2c/include/embree4/rtcore_device.h#L94C1-L95C60

/* Returns the string representation for the error code. For example, for RTC_ERROR_UNKNOWN the string "RTC_ERROR_UNKNOWN" will be returned. */
RTC_API const char* rtcGetErrorString(enum RTCError error);

It also seems to be a new function.

[timohl]

This change requires an upgraded embree version

If embree is upgraded, I would prefer using this function instead of switch case, in order to be independent of the actual enum values if future changes might occure:
https://github.com/RenderKit/embree/blob/3c9936cb6bfb21c572503438d7a10a432e885d2c/include/embree4/rtcore_device.h#L94C1-L95C60

/* Returns the string representation for the error code. For example, for RTC_ERROR_UNKNOWN the string "RTC_ERROR_UNKNOWN" will be returned. */
RTC_API const char* rtcGetErrorString(enum RTCError error);

[daizhirui]

@timohl I test it with embree 4.3.3. A new commit is pushed according to your suggestion of using rtcGetErrorString. Now it is safe to merge if the current embree version being used has this function.

[timohl]

The additional enum value and rtcGetErrorString are actually new in v4.3.3 which was released last week.

The main branch of open3D is on v4.3.1:

Open3D/3rdparty/embree/embree.cmake

Lines 70 to 71 in f02e7d2

	URL https://github.com/embree/embree/archive/refs/tags/v4.3.1.tar.gz
	URL_HASH SHA256=824edcbb7a8cd393c5bdb7a16738487b21ecc4e1d004ac9f761e934f97bb02a4

See #6665 for the last pull request updating embree.

Maybe you could change the URL and URL_HASH to embree v4.3.3 as well, then the checks can run on the correct version.

[daizhirui]

Okay, another commit is added to upgrade embree.

[timohl]

:LGTM:
Maybe update the title of this pull request and lets see how the checks go. :)

[ssheorey]

Thanks @daizhirui for the PR and thanks @timohl for reviewing!