No checker pattern displayed for alpha transparency areas in rendered image #48180

New Issue

Paul J. Schrenker · 2016-04-17T22:40:52+02:00

Paul J. Schrenker commented

2016-04-17 22:40:52 +02:00

System Information
Mint 17.3 Rosa (Cinnamon)
AMD ATI Radeon HD4200

Blender Version
Broken: 2.77a hash: abf6f08
Worked: (optional)

Short description of error
Transparency (alpha) grid not showing on render with transparent background. Shows solid color instead.

Exact steps for others to reproduce the error
Set sky to transparent in Blender Internal render or Film background to transparent in Cycles render. Click render. Background should render with checker-grid where alpha is transparent but does not. Small preview in compositor on the input node for the render layer does show the alpha grid. Alpha does seem to work in the node mix, and changing render view to different channels shows alpha exists. Problem is it just doesn't display correctly. Changing graphics settings under prefs doesn't seem to affect this either.

**System Information** Mint 17.3 Rosa (Cinnamon) AMD ATI Radeon HD4200 **Blender Version** Broken: 2.77a hash: abf6f08 Worked: (optional) **Short description of error** Transparency (alpha) grid not showing on render with transparent background. Shows solid color instead. **Exact steps for others to reproduce the error** Set sky to transparent in Blender Internal render or Film background to transparent in Cycles render. Click render. Background should render with checker-grid where alpha is transparent but does not. Small preview in compositor on the input node for the render layer does show the alpha grid. Alpha does seem to work in the node mix, and changing render view to different channels shows alpha exists. Problem is it just doesn't display correctly. Changing graphics settings under prefs doesn't seem to affect this either.

Paul J. Schrenker commented

2016-04-17 22:40:52 +02:00

Changed status to: 'Open'

Paul J. Schrenker commented

2016-04-17 22:40:52 +02:00

Added subscriber: @pauljs75

Campbell Barton commented

2016-04-18 01:14:27 +02:00

Added subscriber: @ideasman42

Campbell Barton commented

2016-04-18 01:14:27 +02:00

Cant redo this bug.

Does this happen on a new file (File -> Load Factory Settings)
Could you try with with blender-softwaregl (from official Blender.org releases).
Did this ever work? (check previous releases)
When LMB dragging over the transparent areas, does the A: read as 1 or 0 ?

Cant redo this bug. - Does this happen on a new file (File -> Load Factory Settings) - Could you try with with `blender-softwaregl` (from official Blender.org releases). - Did this ever work? (check previous releases) - When LMB dragging over the transparent areas, does the `A:` read as 1 or 0 ?

Gwenael Le Page commented

2016-04-18 09:01:33 +02:00

Added subscriber: @gwentiv

Gwenael Le Page commented

2016-04-18 09:01:34 +02:00

Seems to work just fine here, same build, with transparent film under cycles or alpha as transparent under BI. Can you share a problem file ?

Paul J. Schrenker commented

2016-04-21 11:33:23 +02:00

https://youtu.be/PdZLmEnkjg8

I'm hoping a video is acceptable for explaining and documenting the situation. I tried to include stuff which I'd think may be relevant. A quick run-through of other programs to show they display the alpha grid ok along with precedent for established expectations. (Not sure if they're using the same method, but that it's working. I don't think too much is broken or out of the ordinary with my setup.) Thus this problem seems to be in Blender. Yet within Blender itself, the transparency grid shows in the compositing node. The scene itself is a default scene, which hasn't been changed from the initial install.

At the end of the video I open a terminal window to show system settings to give an idea of what I'm working with in terms of hardware.

Minor (but annoying?) bug, as the images (and saved images) do have alpha. It's just not being displayed as I'd expect.

https://youtu.be/PdZLmEnkjg8 I'm hoping a video is acceptable for explaining and documenting the situation. I tried to include stuff which I'd think may be relevant. A quick run-through of other programs to show they display the alpha grid ok along with precedent for established expectations. (Not sure if they're using the same method, but that it's working. I don't think too much is broken or out of the ordinary with my setup.) Thus this problem seems to be in Blender. Yet within Blender itself, the transparency grid shows in the compositing node. The scene itself is a default scene, which hasn't been changed from the initial install. At the end of the video I open a terminal window to show system settings to give an idea of what I'm working with in terms of hardware. Minor (but annoying?) bug, as the images (and saved images) do have alpha. It's just not being displayed as I'd expect.

Paul J. Schrenker commented

2016-04-23 10:36:32 +02:00

Added system info as recorded by blender 2.76b under Mint 17.3 Rosa (Cinnamon) 64-bit.

Blender_system-info.txt

I also found the failure to display transparency was under these versions:
2.77 (buildbot) hash: 8dcdde5
2.76b hash: f337fea

The last version that runs under Windows XP 32-bit has no problems displaying transparency:
2.76b hash: f337fea

And a video documenting it working under XP: https://youtu.be/numOMB-5npI

Added system info as recorded by blender 2.76b under Mint 17.3 Rosa (Cinnamon) 64-bit. [Blender_system-info.txt](https://archive.blender.org/developer/F305180/Blender_system-info.txt) I also found the failure to display transparency was under these versions: 2.77 (buildbot) hash: 8dcdde5 2.76b hash: f337fea The last version that runs under Windows XP 32-bit has no problems displaying transparency: 2.76b hash: f337fea And a video documenting it working under XP: https://youtu.be/numOMB-5npI

Campbell Barton commented

2016-04-23 11:03:35 +02:00

@pauljs75, thanks for the extra info, please test with blender-softwaregl as requested in my last message.

@pauljs75, thanks for the extra info, please test with `blender-softwaregl` as requested in my last message.

Paul J. Schrenker commented

2016-04-25 09:50:38 +02:00

I tried running "blender -softwaregl" from the terminal as you asked.

The answer is:
In 2.76b (Previous blender version, hash: f337fea), alpha displays correctly. :)

In the build of 2.77a (thomas-sheix ppa, hash: abf6f08), it does not. (I suspect other parts or dependencies which I may have forgotten? Still very new to linux, so I'm finding this is a thing with some software. Using the GUI package manager in Mint gives me a list, but I'm not sure which are needed or optional.)

So at least we know in software rendering (with the non-proprietary graphics), it can work.

I tried running "blender -softwaregl" from the terminal as you asked. The answer is: In 2.76b (Previous blender version, hash: f337fea), alpha displays correctly. :) In the build of 2.77a (thomas-sheix ppa, hash: abf6f08), it does not. (I suspect other parts or dependencies which I may have forgotten? Still very new to linux, so I'm finding this is a thing with some software. Using the GUI package manager in Mint gives me a list, but I'm not sure which are needed or optional.) So at least we know in software rendering (with the non-proprietary graphics), it can work.

Sergey Sharybin commented

2016-05-03 13:23:05 +02:00

Added subscriber: @Sergey

Sergey Sharybin commented

2016-05-03 13:23:05 +02:00

@pauljs75, it's blender-softwaregl script, it's not a command line argument (no space before dash). Also please test builds from blender.org sites, not from someone's PPA because those we do not maintain and can't guarantee they're compiled correct.

@pauljs75, it's `blender-softwaregl` script, it's not a command line argument (no space before dash). Also please test builds from blender.org sites, not from someone's PPA because those we do not maintain and can't guarantee they're compiled correct.

Bastien Montagne commented

2016-05-15 11:00:17 +02:00

Added subscriber: @mont29

Bastien Montagne commented

2016-05-15 11:00:17 +02:00

Changed status from 'Open' to: 'Archived'

Bastien Montagne closed this issue

2016-05-15 11:00:17 +02:00

Bastien Montagne self-assigned this 2016-05-15 11:00:17 +02:00

Bastien Montagne commented

2016-05-15 11:00:17 +02:00

Non news since over one week…

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No checker pattern displayed for alpha transparency areas in rendered image #48180