Assert when using prop_tabs_enum #78575

New Issue

Martijn Versteegh · 2020-07-03T16:21:46+02:00

Martijn Versteegh commented

2020-07-03 16:21:46 +02:00

System Information
Operating system: Linux-5.4.0-40-generic-x86_64-with-debian-bullseye-sid 64 Bits
Graphics card: GeForce GTX 760/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 435.21

Blender Version
Broken: version: 2.90.0 Alpha, branch: master, commit date: 2020-07-03 10:56, hash: aab41401f9

Short description of error
Using [prop_tabs_enum ]] in an add-on results in an assert being triggered in ui_block_align_but_to_region ( https:*developer.blender.org/diffusion/B/browse/master/source/blender/editors/interface/interface_align.c ). This happens because ui_but_align_opposite_to_area_align_get returns zero when called in template_ID_tabs ([ https://developer.blender.org/diffusion/B/browse/master/source/blender/editors/interface/interface_templates.c | interface_templates.c ) for this UI element.

ce148716c8 introduced the prop_tabs_enum function with the described behavior.

Exact steps for others to reproduce the error

Open the text editor
Run the following script
Open the scene properties

bl_info = {
    "name": "MWE T78575",
    "author": "Robert Guetzkow",
    "version": (1, 0),
    "blender": (2, 80, 0),
    "location": "Scene properties > Example tab",
    "description": "Minimum working example for T78575",
    "warning": "",
    "wiki_url": "https://developer.blender.org/T78575",
    "category": "3D View"}

import bpy


class ExampleProperties(bpy.types.PropertyGroup):
    enum: bpy.props.EnumProperty(items=[("id_0", "First", "Description of first entry", 0),
                                        ("id_1", "Second", "Description of second entry", 1),
                                        ("id_2", "Third", "Description of third entry", 2)],
                                 name="Mode",
                                 default="id_0")


class EXAMPLE_PT_panel(bpy.types.Panel):
    bl_label = "Example Panel"
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"

    def draw(self, context):
        layout = self.layout
        layout.prop_tabs_enum(context.scene.mwe_t78575, "enum")


classes = (ExampleProperties, EXAMPLE_PT_panel)


def register():
    for cls in classes:
        bpy.utils.register_class(cls)
    bpy.types.Scene.mwe_t78575 = bpy.props.PointerProperty(type=ExampleProperties)


def unregister():
    for cls in classes:
        bpy.utils.unregister_class(cls)
    del bpy.types.Scene.mwe_t78575

**System Information** Operating system: Linux-5.4.0-40-generic-x86_64-with-debian-bullseye-sid 64 Bits Graphics card: GeForce GTX 760/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 435.21 **Blender Version** Broken: version: 2.90.0 Alpha, branch: master, commit date: 2020-07-03 10:56, hash: `aab41401f9` **Short description of error** Using [prop_tabs_enum ]] in an add-on results in an assert being triggered in `ui_block_align_but_to_region` ([[ https:*developer.blender.org/diffusion/B/browse/master/source/blender/editors/interface/interface_align.c | interface_align.c ]]). This happens because `ui_but_align_opposite_to_area_align_get` returns zero when called in `template_ID_tabs` ([[ https://developer.blender.org/diffusion/B/browse/master/source/blender/editors/interface/interface_templates.c | interface_templates.c ](https:*docs.blender.org/api/current/bpy.types.UILayout.html#bpy.types.UILayout.prop_tabs_enum)) for this UI element. ce148716c8 introduced the `prop_tabs_enum` function with the described behavior. **Exact steps for others to reproduce the error** 1. Open the text editor 2. Run the following script 3. Open the scene properties ``` bl_info = { "name": "MWE T78575", "author": "Robert Guetzkow", "version": (1, 0), "blender": (2, 80, 0), "location": "Scene properties > Example tab", "description": "Minimum working example for T78575", "warning": "", "wiki_url": "https://developer.blender.org/T78575", "category": "3D View"} import bpy class ExampleProperties(bpy.types.PropertyGroup): enum: bpy.props.EnumProperty(items=[("id_0", "First", "Description of first entry", 0), ("id_1", "Second", "Description of second entry", 1), ("id_2", "Third", "Description of third entry", 2)], name="Mode", default="id_0") class EXAMPLE_PT_panel(bpy.types.Panel): bl_label = "Example Panel" bl_space_type = "PROPERTIES" bl_region_type = "WINDOW" bl_context = "scene" def draw(self, context): layout = self.layout layout.prop_tabs_enum(context.scene.mwe_t78575, "enum") classes = (ExampleProperties, EXAMPLE_PT_panel) def register(): for cls in classes: bpy.utils.register_class(cls) bpy.types.Scene.mwe_t78575 = bpy.props.PointerProperty(type=ExampleProperties) def unregister(): for cls in classes: bpy.utils.unregister_class(cls) del bpy.types.Scene.mwe_t78575 ```

Martijn Versteegh commented

2020-07-03 16:21:46 +02:00

Added subscriber: @Baardaap

Philip Holzmann commented

2020-07-03 17:01:32 +02:00

Added subscriber: @Foaly

Philip Holzmann commented

2020-07-03 17:01:32 +02:00

I cannot reproduce.
blender-2.90.0- 5a13f682ee -linux64

I cannot reproduce. blender-2.90.0- 5a13f682ee5f -linux64

Robert Guetzkow commented

2020-07-03 17:13:06 +02:00

Added subscriber: @rjg

Robert Guetzkow commented

2020-07-03 17:13:06 +02:00

I can't reproduce this with the same commit nor with the current master. For this error to occur, you would have to have an uiBut that doesn't fit in any of the alignment categories that are listed in ui_block_align_but_to_region .

I can't reproduce this with the same commit nor with the current master. For this error to occur, you would have to have an `uiBut` that doesn't fit in any of the alignment categories that are listed in [ui_block_align_but_to_region ](https://developer.blender.org/diffusion/B/browse/master/source/blender/editors/interface/interface_align.c$367).

Martijn Versteegh commented

2020-07-03 17:16:04 +02:00

Strange. It's a straight debug build of master without any patches. I'll check if there's an addon causing this, I though I disabled them all, but maybe I overlooked one.

Martijn Versteegh commented

2020-07-03 17:17:54 +02:00

An add-on should't cause asserts I think? So then it would still be a bug?

Martijn Versteegh commented

2020-07-03 17:25:10 +02:00

That's it. The assert is caused by this add-on

https://github.com/mrossini-ethz/camera-calibration-pvr.git

Which I forgot to disable.

Does this still count as a bug or is this considered a bug in the add-on?

That's it. The assert is caused by this add-on https://github.com/mrossini-ethz/camera-calibration-pvr.git Which I forgot to disable. Does this still count as a bug or is this considered a bug in the add-on?

Robert Guetzkow commented

2020-07-03 18:11:55 +02:00

@Baardaap I'll take a look. It depends on whether the Python API is used correctly.

Robert Guetzkow commented

2020-07-03 18:14:02 +02:00

@Baardaap Which version of the add-on are you using? There are two branches for 2.8 and a devel branch.

Martijn Versteegh commented

2020-07-03 18:59:19 +02:00

I have 30d2682 from the blender-2.80 branch

Robert Guetzkow commented

2020-07-04 11:42:02 +02:00

This appear to be a bug in the add-on. Parts of the unfinished UI code has been disabled in commit ab9dfff41f7cb333c707f41052fc0c2c15ead9f5.

This appear to be a bug in the add-on. Parts of the unfinished UI code has been disabled in commit [ab9dfff41f7cb333c707f41052fc0c2c15ead9f5](https://github.com/mrossini-ethz/camera-calibration-pvr/commit/ab9dfff41f7cb333c707f41052fc0c2c15ead9f5).

Robert Guetzkow commented

2020-07-04 12:43:39 +02:00

The source of the issue appears to be layout.prop_tabs_enum(props, "perspective"). This appears to be a bug.

The API change was introduced in ce148716c8 which also added ui_but_align_opposite_to_area_align_get and modified template_ID_tabs (interface_templates.c ). Previously the alignment was assigned as:

const int but_align = (region->alignment == RGN_ALIGN_TOP) ? UI_BUT_ALIGN_DOWN : UI_BUT_ALIGN_TOP;

After the change it is:

const int but_align = ui_but_align_opposite_to_area_align_get(region);

ui_but_align_opposite_to_area_align_get may return zero, which happens in this case and results in the assert being triggered in ui_block_align_but_to_region (interface_align.c )

The source of the issue appears to be `layout.prop_tabs_enum(props, "perspective")`. This appears to be a bug. The API change was introduced in ce148716c8 which also added `ui_but_align_opposite_to_area_align_get` and modified `template_ID_tabs` ([interface_templates.c ](https://developer.blender.org/diffusion/B/browse/master/source/blender/editors/interface/interface_templates.c)). Previously the alignment was assigned as: ``` const int but_align = (region->alignment == RGN_ALIGN_TOP) ? UI_BUT_ALIGN_DOWN : UI_BUT_ALIGN_TOP; ``` After the change it is: ``` const int but_align = ui_but_align_opposite_to_area_align_get(region); ``` `ui_but_align_opposite_to_area_align_get` may return zero, which happens in this case and results in the assert being triggered in `ui_block_align_but_to_region` ([interface_align.c ](https://developer.blender.org/diffusion/B/browse/master/source/blender/editors/interface/interface_align.c))

Robert Guetzkow commented

2020-07-04 14:03:21 +02:00

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

Robert Guetzkow changed title from ~~BLI_Assert(0) when deleting anything from the outliner.~~ to Assert when using prop_tabs_enum

2020-07-04 14:04:20 +02:00

Robert Guetzkow commented

2020-07-04 14:12:46 +02:00

Added subscriber: @JulianEisel