POV-Ray Parse Error or Empty Render when Using Camera Angle (Homebrew macOS build 3.7.0.10)

[heldercpp]

Output of brew config

HOMEBREW_VERSION: 4.6.18-46-g766e574
ORIGIN: https://github.com/Homebrew/brew
HEAD: 766e574070306445bdd0db31b7840181c30fecd0
Last commit: 4 hours ago
Branch: main
Core tap JSON: 24 Oct 21:27 UTC
Core cask tap JSON: 24 Oct 21:27 UTC
HOMEBREW_PREFIX: /opt/homebrew
HOMEBREW_CASK_OPTS: []
HOMEBREW_DOWNLOAD_CONCURRENCY: 16
HOMEBREW_FORBID_PACKAGES_FROM_PATHS: set
HOMEBREW_MAKE_JOBS: 8
HOMEBREW_SORBET_RUNTIME: set
Homebrew Ruby: 3.4.5 => /opt/homebrew/Library/Homebrew/vendor/portable-ruby/3.4.5/bin/ruby
CPU: octa-core 64-bit arm_firestorm_icestorm
Clang: 17.0.0 build 1700
Git: 2.50.1 => /Library/Developer/CommandLineTools/usr/bin/git
Curl: 8.7.1 => /usr/bin/curl
macOS: 26.1-arm64
CLT: 26.0.0.0.1.1757719676
Xcode: N/A
Rosetta 2: false

Output of brew doctor

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Description of issue

POV-Ray Parse Error or Empty Render when Using Camera Angle (Homebrew macOS build 3.7.0.10.unoficia)

Description

When rendering a simple POV-Ray scene, there are two different issues depending on whether the angle parameter is specified in the camera.

---

Case 1 — Without angle

camera {
  location <0, 0, -5>
  look_at <0, 0, 0>
  // angle omitted on purpose
}
sphere { <0, 0, 0>, 1 pigment { color rgb <1, 0, 0> } }
light_source { <0, 10, -10> color rgb <1, 1, 1> }

Command:

povray +W400 +H400 +Itest.pov +Otest.png

Output:

File 'test.pov' line 5: Parse Error: Viewing angle has to be smaller than 180
degrees.
Fatal error in parser: Cannot parse input.
Render failed

The render fails immediately due to a parser error.

---

Case 2 — With angle

camera {
  location <0, 0, -5>
  look_at <0, 0, 0>
  angle 90
}
sphere { <0, 0, 0>, 1 pigment { color rgb <1, 0, 0> } }
light_source { <0, 10, -10> color rgb <1, 1, 1> }

Output:

Ray->Shape Intersection
Sphere   480000   0   0.00%

No intersections are detected, and the resulting image is completely blank.
This happens for any angle below 180.

---

This error did not happen in the last version of the povray.

[SMillerDev]

Did you try reporting this to the developers?

[heldercpp]

This issue has been reported before, but there’s still no proper fix.
The following related issues might be relevant:

• POV-Ray issue #460
• Void Linux issue #55478

From what I’ve seen, the only known workaround is to rebuild POV-Ray with an older GCC runtime library.
In my case, POV-Ray stopped working a few weeks ago, right after running brew upgrade on my macOS system.

It seems the problem might be linked to compiler optimization or floating-point behavior differences in recent GCC/Clang builds.
Is there a way to build POV-Ray through Homebrew with specific compiler flags disabled (for example, to override fast math optimisations), or to force a rebuild using an older GCC version?

[cho-m]

We don't use GCC on macOS. It may be that newer Apple Clang 1700 (LLVM 19) included in recent Xcode uses similar optimization to GCC 13+.

Most likely workarounds are to either:

• Disable povray's extra optimizations (--disable-optimiz), which is what Linux distros like Debian¹ and Fedora² do.
  • EDIT: As note, this will just behave like -fno-fast-math as brew overrides other optimizations like -O and -march.
• Add ENV.append_to_cflags "-fno-finite-math-only" which is what NixOS does³

Footnotes

1. https://salsa.debian.org/debian/povray/-/blob/main/debian/rules?ref_type=heads#L33 ↩

2. https://src.fedoraproject.org/rpms/povray/blob/rawhide/f/povray.spec#_80 ↩

3. https://github.com/NixOS/nixpkgs/blob/nixos-unstable/pkgs/by-name/po/povray/package.nix#L62 ↩

[cho-m]

• povray: --disable-optimiz and fix HEAD on Tahoe homebrew-core#251172

[heldercpp]

Thanks, that solved the problem!