OpenGL render ignores Alpha Mode and Anti-Aliasing settings #47159

New Issue

Mikhail Rachinskiy · 2016-01-11T08:57:11+01:00

2016-01-11 08:57:11 +01:00

System Information
Windows 8.1 x64
Renderer: GeForce GTX 860M/PCIe/SSE2

Blender Version
Broken: 2.76.5 3da0af1
Worked: 2.76b release

Short description of error
OpenGL render gives transparent background with Alpha Mode setting set to Sky, and with no Anti-Aliasing (AA will work if Full Sample enabled).

Exact steps for others to reproduce the error

Open Blender (default scene, factory settings)
Use OpenGL render
Result: transparent background and no AA

**System Information** Windows 8.1 x64 Renderer: GeForce GTX 860M/PCIe/SSE2 **Blender Version** Broken: 2.76.5 3da0af1 Worked: 2.76b release **Short description of error** OpenGL render gives transparent background with Alpha Mode setting set to Sky, and with no Anti-Aliasing (AA will work if Full Sample enabled). **Exact steps for others to reproduce the error** - Open Blender (default scene, factory settings) - Use OpenGL render Result: transparent background and no AA

Mikhail Rachinskiy commented

2016-01-11 08:57:11 +01:00

Changed status to: 'Open'

Mikhail Rachinskiy commented

2016-01-11 08:57:11 +01:00

Added subscriber: @MikhailRachinskiy

Campbell Barton self-assigned this 2016-01-11 11:22:53 +01:00

Campbell Barton commented

2016-01-11 12:12:49 +01:00

Changed status from 'Open' to: 'Archived'

Campbell Barton closed this issue

2016-01-11 12:12:49 +01:00

Campbell Barton commented

2016-01-11 12:12:49 +01:00

Looks like this is intended behavior 2081fd1d7d

Updated documentation: https://www.blender.org/manual/render/opengl.html#settings

Looks like this is intended behavior 2081fd1d7d Updated documentation: https://www.blender.org/manual/render/opengl.html#settings

Mikhail Rachinskiy commented

2016-01-11 13:29:59 +01:00

Jesus could this be even more confusing? Why there is a specific OpenGL alpha mode option?

From documentation:

Some graphics cards don’t support this feature (known as the frame-buffer multi-sample OpenGL extensions).
In this case rendering works but no anti-aliasing is performed.

So why AA works on my Intel card with 2.76 release, and doesn't work with current mater?

System info:
Renderer: Intel(R) HD Graphics 4600
Version: '4.3.0 - Build 10.18.10.3960'
GL_EXT_framebuffer_multisample — is in the extensions list of system-info, so I guess AA should be supported?

Sorry I didn't include that in the first place.

Jesus could this be even more confusing? Why there is a specific OpenGL alpha mode option? ![am.png](https://archive.blender.org/developer/F272505/am.png) From documentation: ``` Some graphics cards don’t support this feature (known as the frame-buffer multi-sample OpenGL extensions). In this case rendering works but no anti-aliasing is performed. ``` So why AA works on my Intel card with 2.76 release, and doesn't work with current mater? **System info:** Renderer: Intel(R) HD Graphics 4600 Version: '4.3.0 - Build 10.18.10.3960' GL_EXT_framebuffer_multisample — is in the extensions list of system-info, so I guess AA should be supported? Sorry I didn't include that in the first place.

Campbell Barton commented

2016-01-11 15:43:59 +01:00

There is no specific OpenGL alpha mode option, this is the same as Blender Internal, Its added to the menu since other render engines won't necessarily show this option.
2.76 release, did not support multi-sample OpenGL extensions (it was always full-samples).

- There is no specific OpenGL alpha mode option, this is the same as Blender Internal, Its added to the menu since other render engines won't necessarily show this option. - 2.76 release, did not support multi-sample OpenGL extensions (it was always full-samples).

Campbell Barton commented

2016-01-11 15:57:49 +01:00

Intel graphics cards on windows miss GL_EXT_framebuffer_multisample_blit_scaled, though they're capable of it since the Linux drivers support it.
See code: https://developer.blender.org/diffusion/B/browse/master/source/blender/gpu/intern/gpu_framebuffer.c;8d9ffa1a6f8ce0c5729dd2f89abb3fa8d0872698$468-477

Added note in docs: https://www.blender.org/manual/render/opengl.html#opengl-anti-aliasing-support

Intel graphics cards on windows miss `GL_EXT_framebuffer_multisample_blit_scaled`, though they're capable of it since the Linux drivers support it. See code: https://developer.blender.org/diffusion/B/browse/master/source/blender/gpu/intern/gpu_framebuffer.c;8d9ffa1a6f8ce0c5729dd2f89abb3fa8d0872698$468-477 Added note in docs: https://www.blender.org/manual/render/opengl.html#opengl-anti-aliasing-support

Mikhail Rachinskiy commented

2016-01-11 17:07:27 +01:00

There is no specific OpenGL alpha mode option

It’s says right there: “OpenGL Render Options”—from the user’s point of view that is quite specific.

Don’t you see the problem? To get background visible on render users need to set two options now, one of which does not indicate in any way that it’s controlling alpha, if either of those two options not in the right state—no background on render (plus frustration). And how would user know that World Background setting controlling OpenGL alpha in the first place?

Wouldn’t be better if Blender Internal alpha mode setting will be ignored and World Background will be the new alpha mode setting for OpenGL render?
Like so:

May be better to hand this case to the UI team? That is certainly topic for discussion.

``` There is no specific OpenGL alpha mode option ``` It’s says right there: “OpenGL Render Options”—from the user’s point of view that is quite specific. Don’t you see the problem? To get background visible on render users need to set two options now, one of which does not indicate in any way that it’s controlling alpha, if either of those two options not in the right state—no background on render (plus frustration). And how would user know that World Background setting controlling OpenGL alpha in the first place? Wouldn’t be better if Blender Internal alpha mode setting will be ignored and World Background will be the new alpha mode setting for OpenGL render? Like so: ![nw.png](https://archive.blender.org/developer/F272603/nw.png) May be better to hand this case to the UI team? That is certainly topic for discussion.

Campbell Barton commented

2016-03-14 12:18:51 +01:00

Changed status from 'Archived' to: 'Resolved'

Campbell Barton commented

2016-03-14 12:18:51 +01:00

Changed behavior of alpha mode 1bae9c6a5b.

Changed behavior of alpha mode 1bae9c6a5b.

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OpenGL render ignores Alpha Mode and Anti-Aliasing settings #47159