Vray 7.30.20 Blender 5.1.2 - Never actually finishes render!

V-Ray for Blender V-Ray for Blender :: Issues
1

Hello

A very frustrating issue, I’ve been developing pipeline for vray blender and I though I broken my code all the way till I decided to hand render it and boom its vray.

Anyway I got 2 path of initializing render :

Option 1 — Native Blender write (Blender saves the result):
  import bpy
  scene = bpy.context.scene
  scene.render.engine = 'VRAY_RENDER_RT'

  scene.render.image_settings.file_format = 'OPEN_EXR'      # 'PNG' / 'JPEG' / ...
  scene.render.filepath = r"C:\path\out\beauty"

  bpy.ops.render.render('INVOKE_DEFAULT', write_still=True)  # Blender's native writer saves it

  Option 2 — V-Ray write, INVOKE_DEFAULT (V-Ray saves the result):
  import bpy
  scene = bpy.context.scene
  scene.render.engine = 'VRAY_RENDER_RT'

  # V-Ray writes the file itself:
  scene.vray.Exporter.auto_save_render = True
  scene.vray.Exporter.animation_mode   = 'FRAME'
  scene.vray.SettingsOutput.img_dir    = r"C:\path\out"
  scene.vray.SettingsOutput.img_file   = "beauty"
  scene.vray.SettingsOutput.img_format = '5'                # '0'=PNG, '1'=JPEG, '5'=OpenEXR

  scene.render.use_lock_interface = True
  bpy.context.preferences.view.render_display_type = 'NONE' # VFB only

  bpy.ops.render.render('INVOKE_DEFAULT')                   # no write_still; V-Ray saves via SettingsOutput

A render log :

[09:01:53.004] Log warnings and errors flag is cleared
[09:01:53.004] Log cleared
[09:02:09.304] GI engines: 'Brute force' and 'Light cache'
[09:02:09.304] Preparing renderer...
[09:02:09.481] Using Intel Embree ray server
[09:02:09.497] Warning : [OCIOColorSpaceManager::init] -1: Error: Loading the OCIO profile 'S:\01_Code\Projects\apps\blender\blender-5.1.2-windows-x64\5.1\datafiles\colormanagement\config.ocio' failed. This .ocio config  'S:\01_Code\Projects\apps\blender\blender-5.1.2-windows-x64\5.1\datafiles\colormanagement\config.ocio' is version 2.5. This version of the OpenColorIO library (2.4.2) is not able to load that config version.
The minor version 5 is not supported for major version 2. Maximum minor
[09:02:09.499] Preparing scene for rendering... [ 0h  0m  0.0s] [ 0h  0m  0.0s est] (0.0%)
[09:02:09.499] Creating bitmap manager
[09:02:09.499] Bitmap manager created.
[09:02:09.500] Warning : BRDFScanned file "C:\Users\tobias\Documents\Chaos Cosmos\Packages\Materials\Leather\Leather_Black_005_15_0cm_33a6a0aa\33a6a0aa_Leather_Black_005_15.0cm.vrscan" failed to load.
[09:02:09.500] Warning : BRDFScanned file "C:\Users\tobias\Documents\Chaos Cosmos\Packages\Materials\Leather\Leather_Black_Alcantara_Perforated_11_59cm_b38f3fc4\b38f3fc4_Leather_Black_Alcantara_Perforated_11.59cm.vrscan" failed to load.
[09:02:09.501] Warning : BRDFScanned file "C:\Users\tobias\Documents\Chaos Cosmos\Packages\Materials\Paper\Suedel_-_sr005_30_97cm_b70472ba\b70472ba_Suedel_-_sr005_30.97cm.vrscan" failed to load.
[09:02:09.506] Warning : BRDFScanned file "C:\Users\tobias\Documents\Chaos Cosmos\Packages\Materials\Car_paint\Carpaint_White_003_0_9cm_52a2fa4e\52a2fa4e_Carpaint_White_003_0.9cm.vrscan" failed to load.
[09:02:09.507] Tiled texture cache set to 0 MB
[09:02:09.507] Preparing scene for rendering...: done [ 0h  0m  0.0s] (100.0%)
[09:02:09.507] Light tree is enabled with clamp coefficient 0.1 and even split coefficient 0.5.
[09:02:09.520] Using lowest thread priority.
[09:02:09.520] Max ray intensity is enabled: rendered result may have incorrect brightness.
[09:02:09.520] Consistent lighting elements are enabled.
[09:02:09.520] Registered 3 internal light select elements.
[09:02:09.521] Preparing scene for frame... [ 0h  0m  0.0s] [ 0h  0m  0.0s est] (0.0%)
[09:02:09.544] Preparing scene for frame...: done [ 0h  0m  0.0s] (100.0%)
[09:02:10.211] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\3DCollective_TexturePack01_CarbonFiber_Height copy6 copy.tif" loaded.
[09:02:15.927] Compiling geometry...: done [ 0h  0m  6.4s] (100.0%)
[09:02:15.927] Using Embree ray tracing.
[09:02:15.927] Using per-object Embree static geometry.
[09:02:16.029] Building Embree static accelerator...: done [ 0h  0m  0.1s] (100.0%)
[09:02:16.029] Building Embree static trees took 102 milliseconds, memory used 269.45 MB
[09:02:16.366] Building Embree moving trees...: done [ 0h  0m  0.3s] (100.0%)
[09:02:16.366] Building Embree moving trees took 337 ms, memory used 576.12 MB
[09:02:16.367] Embree dynamic geometry tree contains 43 primitives.
[09:02:16.367] Embree dynamic geometry tree built in 0.09 ms.
[09:02:16.367] Building Embree dynamic geometry tree...: done [ 0h  0m  0.0s] (100.0%)
[09:02:16.367] Embree dynamic geometry tree takes 0.01 MB.
[09:02:16.367] Embree instance tree uses 0.00 MB.
[09:02:16.367] Preparing Cryptomatte render elements
[09:02:16.367] Volumes tree contains 0 volume primitives.
[09:02:16.367] Scanning scene for light plugins.
[09:02:16.368] 7 lights found.
[09:02:16.368] Using adaptive light evaluation with 8 lights.
[09:02:16.375] Using 2.06 MB for adaptive lights buffer
[09:02:16.375] CausticBeamsManager memory usage: 0.00 MB
[09:02:16.375] Refractive caustics info:
[09:02:16.375] Total nodes: 0, Leaf nodes: 0, Unfinalized nodes: 0
[09:02:16.375] Reflective caustics info:
[09:02:16.375] Total nodes: 0, Leaf nodes: 0, Unfinalized nodes: 0
[09:02:16.375] Generating caustic beams took 0 ms.
[09:02:16.375] Building light cache.
[09:02:16.388] Tracing 1000000 image samples for light cache in 64 passes.
[09:02:16.403] Using 127.49 MB for light cache preview buffer
[09:02:16.687] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\Wipe_Marks_seulfhtc_4K_Roughness.jpg" loaded.
[09:02:16.718] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\mesh_6_sq_AM.png" loaded.
[09:02:16.960] Warning : Bitmap file "S:\01_Code\Icarus\icarusProjectTests\01_BUGS\26_tobiasBlender\..\..\..\..\..\..\..\..\..\Users\tobias\Downloads\Base for hdri.png" failed to load: error in file format:3: The system cannot find the path specified.
[09:02:17.168] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\carbon.jpg" loaded.
[09:02:17.281] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\Decals_01_trasperency" loaded.
[09:02:17.302] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\ExteriorOSTn.jpg" loaded.
[09:02:17.321] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\plate_911.jpg" loaded.
[09:02:17.323] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\brushed_m.jpg" loaded.
[09:02:17.348] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\Decals_01" loaded.
[09:02:17.416] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\Porsche_Gemini 3 (Nano Banana Pro)_2026-03-03_12-11-44.png" loaded.
[09:02:17.451] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\3DCollective_TexturePack01_HFNoise" loaded.
[09:02:17.579] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\3.png" loaded.
[09:02:17.638] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\3DCollective_TexturePack01_CarbonFiber_Height" loaded.
[09:02:17.660] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\3DCollective_TexturePack01_CarbonFiber_Horizontal_mask" loaded.
[09:02:17.693] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\PZ4_BaseColor_DIRT.png.001" loaded.
[09:02:17.749] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\3DCollective_TexturePack01_Flakes_Densidad_MuyAlta" loaded.
[09:02:18.190] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\PZ4_AO.png" loaded.
[09:02:18.384] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\PZ4_Normal.png" loaded.
[09:02:18.633] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\PZ4_Glossy_DIRT.png.001" loaded.
[09:02:18.684] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\interior_bump.jpg" loaded.
[09:02:18.692] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\mesh_6_sq_AM" loaded.
[09:02:18.735] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\interior_stripes" loaded.
[09:02:19.665] Bitmap file "C:\Users\Master\AppData\Local\Temp\blender_a05044\vray_blender\logo.jpg" loaded.
[09:02:20.035] Building light cache...: done [ 0h  0m  3.6s] (100.0%)
[09:02:20.053] Merging light cache passes.
[09:02:20.072] Merging light cache passes...: done [ 0h  0m  0.0s] (100.0%)
[09:02:20.077] Light cache contains 2405 samples.
[09:02:20.077] Light cache base memory usage is 0.8 MB.
[09:02:20.077] Light cache memory usage for 12 light select elements is 0.6 MB.
[09:02:20.077] Saving light cache to file "S:\01_Code\Icarus\icarusProjectTests\01_BUGS\26_tobiasBlender\auto_save_cache.vrlmap"...
[09:02:20.093] Light cache saved successfully
[09:02:20.093] Using premultiplied light cache.
[09:02:22.671] Rendering image...: done [ 0h  0m  2.6s] (100.0%)
[09:02:22.672] Number of raycasts: 42925701 (45.00 per pixel)
[09:02:22.672]   Camera rays: 1986317 (2.08 per pixel)
[09:02:22.672]   Shadow rays: 24286724 (25.46 per pixel)
[09:02:22.672]   GI rays: 10118464 (10.61 per pixel)
[09:02:22.672]   Reflection rays: 5950743 (6.24 per pixel)
[09:02:22.672]   Refraction rays: 383320 (0.40 per pixel)
[09:02:22.672]   Unshaded rays: 3342770 (3.50 per pixel)
[09:02:22.672] Peak memory for frame 1001: 5.94 GiB collected for 22 categories
[09:02:22.672]   Peak memory for "Bitmap": 1.26 GiB
[09:02:22.672]   Peak memory for "Bucket image sampler": 1.21 GiB
[09:02:22.672]   Peak memory for "Dynamic displaced geometry": 0 B
[09:02:22.672]   Peak memory for "Dynamic geometry": < 1 MiB
[09:02:22.672]   Peak memory for "Dynamic moving displaced geometry": 0 B
[09:02:22.672]   Peak memory for "Dynamic moving geometry": 0 B
[09:02:22.672]   Peak memory for "GI": 4.66 MiB
[09:02:22.672]   Peak memory for "Lights": 5.27 MiB
[09:02:22.672]   Peak memory for "Misc.": 1.59 GiB
[09:02:22.672]   Peak memory for "Misc. displaced geometry": 0 B
[09:02:22.672]   Peak memory for "Misc. geometry": 191.62 MiB
[09:02:22.672]   Peak memory for "Misc. moving displaced geometry": 0 B
[09:02:22.672]   Peak memory for "Misc. moving geometry": 0 B
[09:02:22.672]   Peak memory for "Progressive image sampler": 0 B
[09:02:22.672]   Peak memory for "Static displaced geometry": 0 B
[09:02:22.672]   Peak memory for "Static geometry": 45.71 MiB
[09:02:22.672]   Peak memory for "Static hair": 0 B
[09:02:22.672]   Peak memory for "Static moving displaced geometry": 1.37 GiB
[09:02:22.672]   Peak memory for "Static moving geometry": 29.86 MiB
[09:02:22.672]   Peak memory for "Static moving hair": 0 B
[09:02:22.672]   Peak memory for "Tiled bitmap": 0 B
[09:02:22.672]   Peak memory for "VFB": 244.75 MiB
[09:02:22.672] CausticBeamsManager memory usage: 0.00 MB
[09:02:22.672] Refractive caustics info:
[09:02:22.672] Total nodes: 0, Leaf nodes: 0, Unfinalized nodes: 0
[09:02:22.672] Reflective caustics info:
[09:02:22.672] Total nodes: 0, Leaf nodes: 0, Unfinalized nodes: 0
[09:02:22.672] Light cache utilization: 65.40%
[09:02:22.672] Premultiplied light cache utilization: 71.73%
[09:02:22.672] Number of light evaluations: 32955439 (34.54 per pixel)
[09:02:22.700] Maximum memory usage for resman: 3815.23 MB
[09:02:23.206] Clearing geometry...: done [ 0h  0m  0.3s] (100.0%)
[09:02:23.206] Number of intersectable primitives: 7894762
[09:02:23.206]   SD triangles: 3981916
[09:02:23.206]   MB triangles: 3912803
[09:02:23.207]   Static primitives: 43
[09:02:23.207]   Moving primitives: 0
[09:02:23.207]   Infinite primitives: 0
[09:02:23.207]   Static hair segments: 0
[09:02:23.207]   Moving hair segments: 0
[09:02:25.700] Successfully written image file "C:\path\out\beauty.1001.exr"

Then the render is stuck, once I stop it in VFB I get this :

[09:02:31.261] Cleaning up bitmap manager
[09:02:31.404] Maximum memory usage for texman: 0.00 MB
[09:02:31.426] Maximum memory usage for attributes: 0.00 MB

Im asking if I can share scene for testing ( where can I upload it? ). Also pressing F12, render directly via gui does not save renders either.

So this is somehow very broken, the fact that vray don’t finish render/completes is quite a major… problem in both gui/python.

Any help would be great!

2

You can share your scene through support.chaos.com. We do not support Blender’s output system and do not really have plans on supporting it any time soon. Your second option with V-Ray’s output does work for me though(at least on simple scenes). Also note that we have our own render operator bpy.ops.vray.render(which is what our Render buttons call) that does some extra stuff. And given that in your logs you also have “Successfully written image file” I would assume that there has to be an image saved somewhere. That being said in our tests suite(which runs in headless i.e. blender with --background)

if animation_mode == 'FRAME':
    frame_start = frame_end = frame_current
else:
    frame_current = frame_start
ex = scene.vray.Exporter
ex.auto_save_render = True              # V-Ray writes the file, NOT Blender
ex.display          = False             # no VFB window
ex.device_type      = CPU|GPU
scene.vray.SettingsOutput.img_format = '0'   # PNG  (+ output path from --render-output passed as a blender command line arg)
scene.render.engine = 'VRAY_RENDER_RT'
bpy.ops.render.render()
3

Hey @bozhidar_ivanov

Thanks for getting back to me, yes simple scene works, but bigger ones explode.

I’ve made ticket with attachment here > Request #494374

Also here is the “new” python loop script for testing.

import bpy

frames = [1, 2, 3]
i = [0]


def on_complete(scene, *args):
    done = frames[i[0]] if i[0] < len(frames) else "?"
    print("render_complete: frame", done, "done")
    i[0] += 1
    bpy.app.timers.register(render_next, first_interval=0.5)


def render_next():
    if i[0] >= len(frames):
        print("ALL DONE")
        return None
    bpy.context.scene.frame_set(frames[i[0]])
    print("rendering frame", frames[i[0]])
    #bpy.ops.render.render('INVOKE_DEFAULT')
    bpy.ops.vray.render() # native vray call?
    return None


# drop handlers left over from prior runs in this session
for h in list(bpy.app.handlers.render_complete):
    if getattr(h, "__name__", "") == "on_complete":
        bpy.app.handlers.render_complete.remove(h)

bpy.app.handlers.render_complete.append(on_complete)
render_next()

Sadly when ever i run via sript, or via F12 gui, it freezes, render fine, then at the end stops never finishes, so loop never finishes.

Also while I have you here, does vray support “frames” mode too? 1;2;3;4;5-40; etc etc?

4

Haven’t had a lot of time to play around but after setting an output directory this seems to work. You just need to set frames_list and use_frame_range like I did below.

import bpy
scene = bpy.context.scene
exp = scene.vray.Exporter
exp.animation_mode = 'ANIMATION'
exp.use_frame_range = False
exp.frames_list = "1,5,10-20:2"         # 1,5,10,12,14,16,18,20
bpy.ops.vray.render(forceMode='ANIMATION')
5

Oh sweet thanks! Will test it, any luck with the stuck render maybe?

6

I was at some point when testing some scripts, but now I can’t. I think it may have been something to do with our operator(since it doesn’t block execution and does different things based on the scene animation mode), but still can’t reproduce it

7

Hey @bozhidar_ivanov

I didnt try animation on this scene yet, only the loop I send you above in python. Were you able to maybe reproduce the issue?

8

I was able to at some point, but I can’t remember how, and now it isn’t happening anymore. Maybe it’s related to the vray.render operator (since it’s node-blocking) or something along those lines. For a start I think you probably need to set animation_mode to frame as I was still animation rendering from your code.

I can’t reproduce it now. I’ve tried a few different things, but it seems to only happen in your scene. If you’re still interested in figuring out why it’s happening, I’ll need some more time to look into it, as I haven’t had a chance to dig deeper yet. However, I’m out of the office next week.