LuxRender will post a variety of log messages as it is starting up and rendering. If there is an error, it will be posted to the log. You can view the log from the Log tab in the GUI, or from the terminal window if using Luxconsole.
This page lists a number of the more common error messages, what usually causes them, and what the user should do next.
The error messages here are listed by when they occur.
There errors occur as LuxRender is loading a scene for rendering. This is the time when most errors will prevent themselves.
Inconsistent Shading Normals in <***> triangles
Cause — A mesh may have normal orientation problems.
Explanation — The mesh has what Lux believes is a normal orientation issue, where one face has a normal pointing up, and another adjacent to it has the normal facing down. This can cause shading artifacts, but the result is usually not visible. It's also possible what it thinks is a normal flip was actually an intentional modeling decision. You can double check your meshes, but if you do not see an obvious problem, you can safely ignore this warning.
Parsing Error in line <***> scenefile-foo.lxs: Syntax error
Cause — Scene file is not formatted correctly
Explanation — This error means there was a formatting error of some kind in the scene file. If this scene file was not hand-edited, this usually means there is a bug or version mismatch in the exporter. Note that if you get a syntax error on line 3 of the lxs file, it means that you used an 0.8+ exporter with an older version of LuxRender, such as 0.7. You should always make sure you are using an exporter version that matches your LuxRender version.
luxCleanup() called while inside world block
Cause — .lxs file is incomplete or corrupt
Explanation — LuxRender scenes files define the geometry and lights in a section of the scene file that starts with the command WorldBegin. At the end of this section is the line WorldEnd that signals the end of the scene description and tells LuxRender to start rendering. If a scene file is incomplete, it will be missing world end, which causes this error. Incomplete scene files are usually the result of an exporter that crashed or aborted part way through the export. Enable debug options if your exporter has any, and see where it may be failing.
Cause — Texture is of the wrong type or was never defined in the scene file.
Explanation — LuxRender was asked to use a texture for a parameter, and for whatever reason, it couldn't find the specified texture. In most cases, the texture was in fact defined, but it was not the proper type. See this section for more information on texture types: LuxRender Textures - Color, Float, and Fresnel Textures
Static loading of
Cause — Usually means LuxRender version is too old and does not support the specified featureExplanation - This error means that LuxRender did not have the "plug-in" (texture, material, surface integrator, renderer, etc) specified in the scene files. Normally, this results from a build that is too old and lacks the feature called for. However, it could be due to a typo in the scene file, or a LuxRender build that was not compiled properly. Make sure your exporter and LuxRender version match and are up-to-date if you are using development versions.
Inconsistent vertex winding, aborting subdivision
Cause — Mesh has bad normals, subdivision was aborted.
Explanation — LuxRender's subdivision requires that mesh normals be consistent, which is not the case. Double check that you have all normals facing out (or in, if need be, as long as they are consistent). The "recalculate normals" command in most modeling packages is convenient here.
These error occur while dealing with render slaves.
Server connect result: BUSYCause — Slave was already running another job Explanation — Render slaves can only run one job at a time. If you have one already in progress, it must be stopped first. Note that if LuxRender is terminated abruptly (killing the process) it will not drop the render slave first, and you must then manually restart the slave.
Internal error: input stream error
Cause — Data could not be transferred for some reason, usually because the cache directory was not writeable.
Explanation — Network slaves receive scene data from the master, such as textures, PLY/STL files, etc. These are cached locally. Luxconsole by default will try and use the directory it was launched from for this. You can specify a different directory with the --cachedir flag