Maniphest T66818

Overlayed Shadows darken stacked areas
Closed, Archived

Assigned To
Antonio Vazquez (antoniov)
Authored By
Randell Acuram (Ranakade)
Jul 13 2019, 12:04 AM
Tags
  • BF Blender
Subscribers
Brecht Van Lommel (brecht)
Randell Acuram (Ranakade)

Description

System Information
Operating system: win 7
Graphics card: gtx 1060

Blender Version
Broken: Release Candidate 1

Short description of error
This problem NEVER existed in the previous versions of the beta from April to May.
what happened?!

(Current Release Candidate)

This is what it's supposed to look like (May 4, 2019)

I already tried adjusting the alpha and opacity, no fix.
This should really be a high priority because 2.80
is about to be released.

Event Timeline

Randell Acuram (Ranakade) created this task.Jul 13 2019, 12:04 AM
Brecht Van Lommel (brecht) assigned this task to Antonio Vazquez (antoniov).Jul 14 2019, 7:21 PM
Antonio Vazquez (antoniov) added a subscriber: Brecht Van Lommel (brecht).Jul 14 2019, 7:29 PM

@Brecht Van Lommel (brecht) This area of code did not changed for months, so not sure what could be the reason.

@Randell Acuram (Ranakade) Could you provide any simple blend file with the problem?

Brecht Van Lommel (brecht) lowered the priority of this task from 90 to 30.Jul 14 2019, 7:34 PM
Randell Acuram (Ranakade) added a comment.Jul 15 2019, 3:46 AM

Back in May, the shadows wouldn't do this kind of thing
*Forgive me for reacting earlier, I was a bit jumpy when I noticed this issue.
where the opacity doubles when strokes are overlapping each other.

Antonio Vazquez (antoniov) added a comment.Jul 15 2019, 9:01 AM

@Randell Acuram (Ranakade) I'm not sure what you expect, but looking at your file the overlap is working as expected.

IIRC there was a change in how the multiply worked because there was bug, maybe this bug is what got the old result you had, but this was wrong. If you have two overlaped areas, the color must be darker.

To solve the issue in your drawing is very easy... just reshape the shadows strokes to no overlap, or just join the shadow area in one stroke only. This last solution is the best because you reduce the number of points and you will get better FPS.

Antonio Vazquez (antoniov) added a comment.Jul 15 2019, 9:59 AM

@Brecht Van Lommel (brecht) I think we cannot consider this as a bug, no?

Brecht Van Lommel (brecht) added a comment.Jul 15 2019, 11:51 AM

@Antonio Vazquez (antoniov), that's up to you to decide.

I imagine it would be useful to have a way to merge all those areas together automatically rather than doubling up shadows. But if existing functionality is supposed to be able to do that I don't know. If not then close as not a bug.

Randell Acuram (Ranakade) added a comment.Jul 15 2019, 3:08 PM
In T66818#722373, @Brecht Van Lommel (brecht) wrote:

@Antonio Vazquez (antoniov), that's up to you to decide.

I imagine it would be useful to have a way to merge all those areas together automatically rather than doubling up shadows. But if existing functionality is supposed to be able to do that I don't know. If not then close as not a bug.

it was much easier to work without the overlaying shadows doubling the opacity in the past, at least i thought so.

Antonio Vazquez (antoniov) changed the task status from Unknown Status to Unknown Status.Jul 15 2019, 3:43 PM
Antonio Vazquez (antoniov) mentioned this in T66293: GPencil: Redesign Blend modes and cleanup Drawing Engine.

I know what you mean, and in this case you would be right, but the problem is the old mode was wrong... any artist expect that if you draw two times on the same place with a semitransparent color, the color will get darker that only one stroke. If draw three times, more darker and so on.

Anyway, we have planned to do a redesign of the blend modes in 2.81 (T66293), so I'm going to take a note to review if it's possible to have this "no-overlap" as an option and make easy this type of shadows.

Thanks for your report, but as this is not a bug, I'm going to archive it.

Randell Acuram (Ranakade) added a comment.Jul 15 2019, 4:42 PM
In T66818#722758, @Antonio Vazquez (antoniov) wrote:

I know what you mean, and in this case you would be right, but the problem is the old mode was wrong... any artist expect that if you draw two times on the same place with a semitransparent color, the color will get darker that only one stroke. If draw three times, more darker and so on.

Anyway, we have planned to do a redesign of the blend modes in 2.81 (T66293), so I'm going to take a note to review if it's possible to have this "no-overlap" as an option and make easy this type of shadows.

Thanks for your report, but as this is not a bug, I'm going to archive it.

Alrighty no problem. thx for looking into it though. :-)