Asset broswer won't show the previews when asset was marked in a background blender #93893

New Issue

yonghao lv · 2021-12-09T11:42:22+01:00

yonghao lv commented

2021-12-09 11:42:22 +01:00

System Information
Operating system: Windows-10-10.0.22483-SP0 64 Bits
Graphics card: NVIDIA GeForce RTX 2080 SUPER/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 472.47

Blender Version
Broken: version: 3.0.0, branch: master, commit date: 2021-12-02 18:35, hash: f1cca30557
Worked: (newest version of Blender that worked as expected)

Short description of error

Only generate previews when open blender and set them in outliner/python
use bpy.ops.wm.previews_batch_generate() for these files will not work(Error below).

ERROR: bpy_struct: item.attr = val: enum "" not found in ('BEST', 'GOOD', 'REALTIME')
*NOT* Saving D:\ASSET\Plane.blend, because some error(s) happened while deleting temp render data...

Exact steps for others to reproduce the error
running this script to mark every object in a blend file as asset

import argparse
import bpy
import sys


def main(args):
    print("Script args: ", args)

    if len(args) > 0:
        parser = argparse.ArgumentParser()
        parser.add_argument('blend')
        parser.add_argument('--pack', action='append')
        args = parser.parse_args(args)

        blend = args.blend

        bpy.ops.wm.open_mainfile(filepath=blend)

        for o in bpy.data.objects:
            bpy.context.scene.collection.objects.link(o)
            o.asset_mark()
            o.asset_generate_preview()

        # pack
        bpy.ops.file.pack_all()
        try:
            bpy.ops.file.pack_libraries()
        except:
            pass

        bpy.context.view_layer.update()
        bpy.context.preferences.filepaths.save_version = 0  # No backup blends needed
        bpy.ops.wm.save_as_mainfile(filepath=blend, compress=True)


if __name__ == "__main__":
    if "--" not in sys.argv:
        argv = []  # as if no args are passed
    else:
        argv = sys.argv[sys.argv.index("--") + 1:]  # get all args after "--"
    main(argv)

**System Information** Operating system: Windows-10-10.0.22483-SP0 64 Bits Graphics card: NVIDIA GeForce RTX 2080 SUPER/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 472.47 **Blender Version** Broken: version: 3.0.0, branch: master, commit date: 2021-12-02 18:35, hash: `f1cca30557` Worked: (newest version of Blender that worked as expected) **Short description of error** ![1639046242(1).png](https://archive.blender.org/developer/F12719041/1639046242_1_.png) Only generate previews when open blender and set them in outliner/python use `bpy.ops.wm.previews_batch_generate()` for these files will not work(Error below). ``` ERROR: bpy_struct: item.attr = val: enum "" not found in ('BEST', 'GOOD', 'REALTIME') *NOT* Saving D:\ASSET\Plane.blend, because some error(s) happened while deleting temp render data... ``` **Exact steps for others to reproduce the error** running this script to mark every object in a blend file as asset ```Py import argparse import bpy import sys def main(args): print("Script args: ", args) if len(args) > 0: parser = argparse.ArgumentParser() parser.add_argument('blend') parser.add_argument('--pack', action='append') args = parser.parse_args(args) blend = args.blend bpy.ops.wm.open_mainfile(filepath=blend) for o in bpy.data.objects: bpy.context.scene.collection.objects.link(o) o.asset_mark() o.asset_generate_preview() # pack bpy.ops.file.pack_all() try: bpy.ops.file.pack_libraries() except: pass bpy.context.view_layer.update() bpy.context.preferences.filepaths.save_version = 0 # No backup blends needed bpy.ops.wm.save_as_mainfile(filepath=blend, compress=True) if __name__ == "__main__": if "--" not in sys.argv: argv = [] # as if no args are passed else: argv = sys.argv[sys.argv.index("--") + 1:] # get all args after "--" main(argv) ```

yonghao lv commented

2021-12-09 11:42:22 +01:00

Added subscriber: @1029910278

Richard Antalik commented

2021-12-09 22:48:09 +01:00

Changed status from 'Needs Triage' to: 'Confirmed'

Julian Eisel commented

2021-12-10 19:44:21 +01:00

Added subscriber: @JulianEisel

Julian Eisel commented

2021-12-10 19:44:21 +01:00

Didn't investigate yet, but my suspicion is that the file is saved before the previews are done generating. This would also be possible to happen for regular GUI use, if the user saves the file fast enough after generating previews. There's no nice solution here I think - either we wait with saving the file until the preview jobs are done, or we accept that the previews are not finished properly. I think waiting is better, even if that can be annoying. For scripts we could make the waiting optional.

Didn't investigate yet, but my suspicion is that the file is saved before the previews are done generating. This would also be possible to happen for regular GUI use, if the user saves the file fast enough after generating previews. There's no nice solution here I think - either we wait with saving the file until the preview jobs are done, or we accept that the previews are not finished properly. I think waiting is better, even if that can be annoying. For scripts we *could* make the waiting optional.

yonghao lv commented

2021-12-12 02:40:53 +01:00

Actually I use a wait to execute script. I am not sure whether saving file will break generating previews.

import subprocess
import os
import bpy

def execute(cmd):
    return subprocess.Popen(cmd, universal_newlines=True)


def execute_blender(args):
    args.insert(0, bpy.app.binary_path)
    print(" ".join(args))
    return execute(args)


def post_process_blend_file(asset,scripts_file_name = 'script_export_blend.py'):
    args = [
        "--background",
        "--factory-startup",
        "--python",
        os.path.join(os.path.dirname(__file__), scripts_file_name),
        "--",
        asset,
    ]

    execute_blender(args).wait()  # Wait for completion.

Actually I use a wait to execute script. I am not sure whether saving file will break generating previews. ```Py import subprocess import os import bpy def execute(cmd): return subprocess.Popen(cmd, universal_newlines=True) def execute_blender(args): args.insert(0, bpy.app.binary_path) print(" ".join(args)) return execute(args) def post_process_blend_file(asset,scripts_file_name = 'script_export_blend.py'): args = [ "--background", "--factory-startup", "--python", os.path.join(os.path.dirname(__file__), scripts_file_name), "--", asset, ] execute_blender(args).wait() # Wait for completion. ```

Sybren A. Stüvel commented

2021-12-14 15:46:02 +01:00

Added subscriber: @dr.sybren

Sybren A. Stüvel commented

2021-12-14 15:46:02 +01:00

Actually I use a wait to execute script.

This makes the current process wait for the sub-process. It doesn't make the sub-process wait with saving until the preview generation is done. In other words: something waits, but not for the right thing.

The waiting should happen between the calls to o.asset_generate_preview() and bpy.ops.wm.save_as_mainfile().

Also, never do this:

      try:
            # code here
      except:
          pass

This hides any errors that may occur, regardless of whether they're expected or not.

> Actually I use a wait to execute script. This makes the current process wait for the sub-process. It doesn't make the sub-process wait with saving until the preview generation is done. In other words: *something* waits, but not for the right thing. The waiting should happen between the calls to `o.asset_generate_preview()` and `bpy.ops.wm.save_as_mainfile()`. Also, never do this: ```Py try: # code here except: pass ``` This hides any errors that may occur, regardless of whether they're expected or not.

Topher Hughes commented

2022-06-03 18:38:19 +02:00

Added subscriber: @hughetop

Topher Hughes commented

2022-06-03 18:38:19 +02:00

I'm running into this issue as well when trying to create library assets programmatically. Looping over selected objects like:

file_path = get_asset_path(obj)
obj.asset_mark()
obj.asset_generate_preview()
# set catalog, tags, description, author
bpy.data.libraries.write(file_path, {obj})

The assets correctly export and the library updates, but none have previews because they are generated in a background thread and aren't ready by the time the bpy.data.libraries.write function is called. Since there's no way to force it to wait for the preview to finish (even obj.preview_ensure() just returns a blank image), is there a way to tell if the preview actually exists? I'm trying to do something like:

while True:
    if preview_finished(obj):
        break
    time.sleep(0.1)

but I have no idea how to tell if the preview is actually finished generating. It seems to immediately create a blank image so obj.preview.image_pixels is never empty.
So is there any way right now to wait for the preview to finish generating, or programmatically determine if the preview is not blank?

Edit: found on a forum post, here's what my preview_finished function is doing

import numpy as np
def preview_finished(obj):
    arr = np.zeros((obj.preview.image_size[0] * obj.preview.image_size[1]) * 4, dtype=np.float32)
    obj.preview.image_pixels_float.foreach_get(arr)
    if np.all((arr == 0)):
        return False
    return True

It's hacky but I'm hoping there will be a more elegant way to do this in the future.

I'm running into this issue as well when trying to create library assets programmatically. Looping over selected objects like: ```Py file_path = get_asset_path(obj) obj.asset_mark() obj.asset_generate_preview() # set catalog, tags, description, author bpy.data.libraries.write(file_path, {obj}) ``` The assets correctly export and the library updates, but none have previews because they are generated in a background thread and aren't ready by the time the `bpy.data.libraries.write` function is called. Since there's no way to force it to wait for the preview to finish (even `obj.preview_ensure()` just returns a blank image), is there a way to tell if the preview actually exists? I'm trying to do something like: ```Py while True: if preview_finished(obj): break time.sleep(0.1) ``` but I have no idea how to tell if the preview is actually finished generating. It seems to immediately create a blank image so `obj.preview.image_pixels` is never empty. So is there any way right now to wait for the preview to finish generating, or programmatically determine if the preview is not blank? Edit: found on a forum post, here's what my `preview_finished` function is doing ```Py import numpy as np def preview_finished(obj): arr = np.zeros((obj.preview.image_size[0] * obj.preview.image_size[1]) * 4, dtype=np.float32) obj.preview.image_pixels_float.foreach_get(arr) if np.all((arr == 0)): return False return True ``` It's hacky but I'm hoping there will be a more elegant way to do this in the future.

Daniel Grauer commented

2022-06-03 18:42:14 +02:00

Added subscriber: @DanielGrauer

Philipp Oeser commented

2023-04-21 10:07:10 +02:00

Is this solved by 2fba27e6d8 (since now this is not run as a job when in background)?

@DanielGrauer @hughetop @1029910278 : could you re-check this in a fresh 3.6 build from https://builder.blender.org/download/daily/ ?

Is this solved by 2fba27e6d8876025b1e98d1a6e35d5fac6749a27 (since now this is not run as a job when in background)? @DanielGrauer @hughetop @1029910278 : could you re-check this in a fresh 3.6 build from https://builder.blender.org/download/daily/ ?

Philipp Oeser added

Status

Needs Information from User

and removed

Status

Confirmed

labels 2023-04-21 10:07:24 +02:00

Daniel Grauer commented

2023-04-24 10:32:47 +02:00

This seems to work for me, all the previews show properly with 3.6 builds when i generate them in the background.

Philipp Oeser commented

2023-04-24 10:44:04 +02:00

This seems to work for me, all the previews show properly with 3.6 builds when i generate them in the background.

good to hear, will wait a bit for others to confirm (in case of no reply, will close in a bit...)

> This seems to work for me, all the previews show properly with 3.6 builds when i generate them in the background. good to hear, will wait a bit for others to confirm (in case of no reply, will close in a bit...)

Topher-Hughes commented

2023-04-24 18:07:51 +02:00

Seems to work with the blender-3.3.6-stable+v33.948f8298b982-windows.amd64-release build. Sorry for the duplicate account, I switched companies (and therefore email addresses).

Philipp Oeser commented

2023-04-27 14:12:31 +02:00

Seems to work with the blender-3.3.6-stable+v33.948f8298b982-windows.amd64-release build. Sorry for the duplicate account, I switched companies (and therefore email addresses).

Good to hear it is working for you as well, so I think we can close now.

> Seems to work with the blender-3.3.6-stable+v33.948f8298b982-windows.amd64-release build. Sorry for the duplicate account, I switched companies (and therefore email addresses). Good to hear it is working for you as well, so I think we can close now.

Philipp Oeser closed this issue

2023-04-27 14:12:34 +02:00

Blender Bot added

Status

Archived

and removed

Status

Needs Information from User

labels 2023-04-27 14:12:35 +02:00

Philipp Oeser added

Status

Resolved