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paulhart
08-28-2018, 02:23 PM
Hello, all you bright NPR people.
I have a project which involves a raven like creature, and have set the Lines on in the Rendering Tab, and set the width to 2 pixels only on the silhouette. For reasons beyond my understanding I am getting the lines "thru" the character, as if it was transparent, yet there is no Transparency set.
Here is a single frame, in which I have overlayed the line render, to make it more clear what the problem is.
Does anybody know what is going on?? I have scratched as many options as I can know, someone wiser, please step in!!
142609

MonroePoteet
08-28-2018, 03:30 PM
It seems to work fine for me in LW2018.0.6. The BirdBody_Simple object just has a plain Principled BSDF surface, the Silhouette edges are set to 2.0mm, and the Edges buffer (don't know about a "Lines" buffer) is enabled in the Render Properties:

142614 Final Render

142611 Edges Buffer (Alpha)

If I put even 1.0% Transparency on the Surface, the edges show through.

142612 Final Render, 1.0% Transparency

142613 Edges Buffer, 1.0% Transparency (Alpha)

It looks like maybe you have an Image of some sort mapped to the Surface. Perhaps the Image has an Alpha channel causing some minimal amount of Transparency which results in the Edges showing through. Otherwise, dunno.

mTp

jwiede
08-28-2018, 04:26 PM
If I put even 1.0% Transparency on the Surface, the edges show through.

142612 Final Render, 1.0% Transparency

142613 Edges Buffer, 1.0% Transparency (Alpha)

OP's problem aside, this edges-v-transparency behavior seems like a pretty serious bug in and of itself. There's no way 1% of transparency should allow those edges to show through as "unaffected" and crystal-clear as they are there. Transparency isn't properly occluding edges, it appears any transparency is treated as if 100% transparency w.r.t. edges.

paulhart
08-28-2018, 04:34 PM
I tend to agree with jwiede above, and thank MonroePoteet for the reply. It helped me locate a 'Bump' image file, that was set to 10%, but I would have thought, 'there is no transparency' involved, and it didn't make any difference. I also agree with jwiede, in that 1.0% Transparency should not cause this much result. I was able to render these lines (Edges) successfully in prior version, as this project has 'baked' for awhile. I tried going thru the Node Editor with a constant plugged into the Silhouette settings, but then, no Edges at all. I will keep looking around, and appreciate any questions and check-in ideas, as something is clearly 'amiss.'
I just tried 'Sharp Creases' only, set to 4pixels, as I want to see the problem clearly, and there it is. The wing of the bird, behind the head, has it's line drawn thru. Grumble???
142617

MonroePoteet
08-28-2018, 04:41 PM
Yes, it's certainly different behavior than LW2015:

142615 Final render, 70% Transparency

142616 70% Alpha channel

142618 Final render, 90% Transparency

142619 90% Alpha channel

mTp

paulhart
08-28-2018, 05:08 PM
I opened the source Layout file for the raven, before it got imported into the current working scene. Silhouette edges worked but the Edge Nodes are intentionally made to look broken. Strange, I took the check mark out of the box for Edit Nodes, hoping just to see the Silhouette Edge, native, but it still processed the Edges thru the Node tree??? Notice, tho, the Silhouette Edge, and Sharp Creases Edge don't violate the Transparency that I had bumped into. I will investigate further.
142620

Sensei
08-29-2018, 04:16 AM
Hello, all you bright NPR people.
I have a project which involves a raven like creature, and have set the Lines on in the Rendering Tab, and set the width to 2 pixels only on the silhouette. For reasons beyond my understanding I am getting the lines "thru" the character, as if it was transparent, yet there is no Transparency set.
Here is a single frame, in which I have overlayed the line render, to make it more clear what the problem is.
Does anybody know what is going on?? I have scratched as many options as I can know, someone wiser, please step in!!
142609

It looks similiar like in your old thread
https://forums.newtek.com/showthread.php?155766-NPR-Line-creation-test!!!-Challenge/page2
I showed you how to fight with it in LW 2018.0.1..

paulhart
08-29-2018, 04:01 PM
Answer from Sensei, from an old thread. Setting the Edge Z Scale to 1.0, seems to be working, tho I have no idea 'when, if, how' it might have gotten set to 0.0???
"I don't know if you were able to get rid of the 'dark silhouette' lines that curve thru the back of the blue sphere.
Set Edge Z Scale to 1.0.

"After adjusting it, incidence trick stopped being needed also.."

Tobian
08-30-2018, 07:38 AM
There's a suface based 'opaque' tick box on the material, does that help at all?

paulhart
08-30-2018, 11:12 AM
Thank you Tobian, I checked, and indeed, on this Surface, I do have the check-mark in the Opaque box.
As near as I can determine, I had Set Edge Z Scale = 0.0, and changing it to 1.0 seems to have been this problem, at the moment.
Here is a recent composite of the Raven, and note that the Silhouette and some Sharp Creases are correct, without any bleed thru.
142639

jwiede
09-01-2018, 09:43 PM
Thank you Tobian, I checked, and indeed, on this Surface, I do have the check-mark in the Opaque box.
As near as I can determine, I had Set Edge Z Scale = 0.0, and changing it to 1.0 seems to have been this problem, at the moment.
Here is a recent composite of the Raven, and note that the Silhouette and some Sharp Creases are correct, without any bleed thru.
142639

Is Edge Z Scale 0.0 the default, perchance?

I'm glad there's a workaround.

However, I'm less than convinced that "Edge Z Scale" has any reasonable justification for affecting whether edges are properly occluded by transparency values. If anything, it seems like "Edge Z Scale" setting is somehow involved in a transparency calculation where it shouldn't be, and its presence there is causing unintended (and undesirable) side-effects.

paulhart
09-02-2018, 03:11 PM
JWiede, thank you. I am of a similar mind, but I am determined not to 'go down that rabbit hole' of 'bug'/product testing, until my next encounter, forces me to. I have moved on the the actual project, which was stalled, with the line problems. Thank you everyone for the assist, and if any other ideas come along, please add them.

jwiede
09-03-2018, 01:34 PM
JWiede, thank you. I am of a similar mind, but I am determined not to 'go down that rabbit hole' of 'bug'/product testing, until my next encounter, forces me to. I have moved on the the actual project, which was stalled, with the line problems. Thank you everyone for the assist, and if any other ideas come along, please add them.

It's okay, I'll file a bug on it if I find myself filing other bugs today. Just glad there's a workaround.