[MtoA] Warning: Renderer “arnold” does not provide batch rendered options


Not all renderers have batch render options, so if you click the box beside the Batch Render menu command:

menu_options_box

then you’ll get a warning:

// Warning: file: C:/Program Files/Autodesk/Maya2017/scripts/others/batchRenderOptions.mel line 19: Renderer "arnold" does not provide batch rendered options. // 
// Warning: file: C:/Program Files/Autodesk/Maya2017/scripts/others/batchRenderOptions.mel line 19: Renderer "mayaHardware" does not provide batch rendered options. // 
// Warning: file: C:/Program Files/Autodesk/Maya2017/scripts/others/batchRenderOptions.mel line 19: Renderer "mayaHardware2" does not provide batch rendered options. // 
// Warning: file: C:/Program Files/Autodesk/Maya2017/scripts/others/batchRenderOptions.mel line 19: Renderer "mayaVector" does not provide batch rendered options. //

All the rendering options for Arnold are in the Arnold Render Settings.

To start a batch render, click the Batch Render text in the Render menu:
render_menu

Vertices and the maximum valence limit


The valence of a vertex is the number of edges connected to that vertex. In Arnold, the maximum valence is 255 (that’s because of the data type we use to store the valence; we minimize the memory requirements since this is stored per-vertex).

If a mesh in the scene has a vertex with more than 255 edges, you’ll get a WARNING like this:

 [polymesh] example_mesh: mesh has at least a vertex with valence higher than 255, disabling subdivision

But if the adaptive subdivision results in a vertex with too many edges, you’ll get an ERROR:

 ERROR: [arnold] [subdiv] example_mesh: edge (144578,287741) in face 263433 has a vertex that exceeded the max valence limit of 255 

[MtoA] The renderer ‘arnold’ used by this scene, is not currently available


warning_renderer_not_currently_available

// Warning: file: C:/Program Files/Autodesk/Maya2017/scripts/others/supportRenderers.mel line 64: The renderer "arnold" used by this scene, is not currently available. The "mayaSoftware" renderer will be used instead. //

By itself, this warning doesn’t mean there’s a problem with MtoA or Arnold. The warning means that the MtoA plugin isn’t loaded, so all you have to do is load MtoA:

  1. Click Windows > Settings/Preferences > Plug-in Manager
  2. Scroll down until you see mtoa.mll
    plug-in_manager_mtoa
  3. Click the Loaded and Auto load check boxes.

However, if you get a “Unable to dynamically load : ../mtoa.mll The specified module could not be found.” error, then that’s a different problem.

[Arnold] Optimizing render utilization


WARNING| Rendering utilization was only 48%. Your render may be bound by a single threaded process or I/O.

In general, if you see this warning about low machine utilization, that means that a significant amount of time is being spent in just one thread, and if you want to render faster, you need to look into possible issues.

  • Reading textures (file I/O) isn’t multi-threaded, so that can reduce machine usage because threads will be waiting while textures are read from disk.Check the amount of texture data “Read from disk” and the “File I/O time”, and compare the amount of texture data with the texture cache size (for example, if you’re reading 5GB of texture data but the cache is just 1GB, you can increase the cache size).
  • Subdivision isn’t multi-threaded yet, so a few huge objects might slow things down. But in general, multiple objects will be subdivided at the same
    time (one thread per object) so it isn’t usually a big issue.
  • Loading standins is also file I/O so each file is loaded in a single thread. File I/O is dependent on the file system, not the CPU speeds, so adding
    more threads to IO won’t help. If this is what is causing your low CPU utilization, the only way to improve that is to get faster disks, file
    servers, networks, etc…
  • Displacement is multi-threaded. A single mesh can be displaced by multiple threads and multiple meshes can be displaced at the same time.
  • Another possible reason for this warning is because there are multiple copies of Arnold running, or Arnold and some other compute-heavy application, so that Arnold can’t get to 100% utilization because Arnold is competing with other processes. You can check your Activity Manager (OSX), Task Manager (Windows), or top (Linux) to see see what else is consuming CPU time.
  • You’ll also see the utilization warning with relatively simple scenes, because the single-threaded work of loading the scene and plugins and textures
    takes longer than the actual rendering.

hat tip: Thiago

WARNING : [ass] node name already in use


Shader nodes must have unique names.

So if you’re using standins, each standin ASS file has to have unique shader node names. Otherwise you’ll get unexpected results when you render, like all standins having the same shading, or some “flickering” in animation if the order of standin loading changes.

In the Arnold log, look for “node name already in use” warnings:

WARNING | [ass] standin_01.ass line 50: node name "aiStandard1SG" already in use
WARNING | [ass] standin_01.ass line 58: node name "aiStandard1" already in use
WARNING | [ass] standin_01.ass line 118: node name "file1" already in use
WARNING | [ass] standin_01.ass line 147: node name "aiNoise1" already in use

 

If each standin should look different, you need to have unique shader names in each ASS file. If you’re using MtoA, that includes the name of the SG node (for example, aiStandard1SG).

WARNING mtoa_shading_groups: unresolved reference


Any time you see “node … is not installed” and “unresolved reference” warnings when you try to kick an ASS file exported from Maya, the problem is missing MtoA shaders.


00:00:00 18MB WARNING | [ass] line 259: node "MayaFile" is not installed
00:00:00 18MB WARNING | [ass] line 288: node "MayaShadingEngine" is not installed

00:00:03 23MB WARNING | [ass] line 238: pSphereShape1.mtoa_shading_groups: unresolved reference to 'aiStandard2SG'
00:00:03 23MB WARNING | [ass] line 137: aiSkyDomeLightShape1.color: unresolved reference to 'file1'
00:00:03 23MB WARNING | [ass] line 188: pPlaneShape1.shader: unresolved reference to 'aiStandard1SG'
00:00:03 23MB WARNING | [ass] line 197: pPlaneShape1.mtoa_shading_groups: unresolved reference to 'aiStandard1SG'
00:00:03 23MB WARNING | [ass] line 229: pSphereShape1.shader: unresolved reference to 'aiStandard2SG'

When you render with kick, you need to specify the location of the MtoA shaders. You can do this several ways:

  • Set the ARNOLD_PLUGIN_PATH environment variable. For example:
    export ARNOLD_PLUGIN_PATH=/home/render/solidangle/mtoa/2016/shaders
    set ARNOLD_PLUGIN_PATH=C:\solidangle\mtoadeploy\2016\shaders
  • Use the kick -l flag to specify the MtoA shader location.
  • In Maya, set the Shader Search Path in the Arnold Render Settings, then export the ASS file.

[RLM] Communications error with license server (­17)


These warnings mean that Arnold can connect to the RLM license server, but Arnold cannot connect to the solidangle ISV server:

00:00:12 14MB WARNING | [rlm] * Communications error with license server (­17)
00:00:12 14MB WARNING | [rlm] * Connection refused at server (­111)

Usually the problem is that the solidangle ISV server is not running.

You can check the status of the solidangle ISV server with RLM Web Admin. I like the get the RLM diagnostics (Diagnostics > Run Diagnostics) from RLM Web Admin and review that.

In rare cases, the problem is something else, such as:

  • Some sort of network connection problem. For example, I recently had a case where we would get these warnings when we used the IP address of the license server in solidangle_LICENSE. But as soon as we switched to using the hostname, everything worked.
  • Another RLM instance is running and listening to port 5053, and that instance doesn’t have a solidangle ISV running. I heard about this second-hand, from a customer; I didn’t see it with my own eyes and I don’t know how it’s possible. You can have multiple RLM instances running, but each instance has to have a different port otherwise you get ” “Port 5053 in use, waiting…” messages and the second RLM won’t start.