Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] Daily Builds => Topic started by: Aram Avetisyan on 2021-10-13, 10:19:07

Title: CoronaDecals playground!
Post by: Aram Avetisyan on 2021-10-13, 10:19:07
Corona Renderer 8 Oct-12 daily build comes with new CoronaDecals!
https://www.dropbox.com/s/26uk33cs6yufcur/corona-8-3dsmax-daily-2021-10-12.exe?dl=1 (https://www.dropbox.com/s/26uk33cs6yufcur/corona-8-3dsmax-daily-2021-10-12.exe?dl=1)
They can be found in Create > Geometry > Corona subtype menu.
You create CoronaDecal, assign a material with or without opacity to it and it will project on all surfaces intersecting its bounding-box.
There is a quickstart scene attached (Max 2019).
Give it a go and share your results here!

(https://forum.corona-renderer.com/index.php?action=dlattach;topic=34613.0;attach=155179;image)
Title: Re: CoronaDecals playground!
Post by: aaouviz on 2021-10-13, 18:14:22
Not bad. Just gave it a shot. A nice quick way to avoid CoronaLayeredMaterial I guess...

One constraint I see is that when I gave it displacement (so it's popping out from the base surface) the base materials displacement is lost. In the same way as only 1 displacement is supported on Layered Material. I'm sure you're well aware of this.

Hope I can put it to good use...!
Title: Re: CoronaDecals playground!
Post by: romullus on 2021-10-13, 19:10:26
One constraint I see is that when I gave it displacement (so it's popping out from the base surface) the base materials displacement is lost. In the same way as only 1 displacement is supported on Layered Material. I'm sure you're well aware of this.

In many cases this is desirable effect (you don't want that asphalt displacement would mix with manhole displacement, right?). An request for option to override some maps and at the same time retain others, is already requested and logged by the team for consideration.
Title: Re: CoronaDecals playground!
Post by: marchik on 2021-10-14, 02:43:32
Yep, I tested everything well again, the fact that the displacements does not mix together removes half of the use cases, I am a little disappointed with that.

A logical option would be when the base layer displacement is ignored only at the place where the decal is overlaid, or giving some options like Only A, Only B, A+B
Title: Re: CoronaDecals playground!
Post by: aaouviz on 2021-10-14, 08:26:23
Yep, I tested everything well again, the fact that the displacements does not mix together removes half of the use cases, I am a little disappointed with that.

A logical option would be when the base layer displacement is ignored only at the place where the decal is overlaid, or giving some options like Only A, Only B, A+B
\

+1
Title: Re: CoronaDecals playground!
Post by: romullus on 2021-10-14, 11:31:44
Yep, I tested everything well again, the fact that the displacements does not mix together removes half of the use cases, I am a little disappointed with that.

A logical option would be when the base layer displacement is ignored only at the place where the decal is overlaid, or giving some options like Only A, Only B, A+B

Wait, i was under impression that that's exactly how decals are working now, i.e. you can have displacement from both, target and projection surfaces, but it looks i was wrong and indeed you can only have displacement either from one or another, but not from both at the same time. That's a huge disappoitment :[ I hope it can be improved before release, otherwise i too find decals' usefulness pretty limited.
Title: Re: CoronaDecals playground!
Post by: Aram Avetisyan on 2021-10-14, 11:45:24
The displacement issue is known, same kind of problem is with normals and their mixing/mapping, some weird stuff happens with LightMtl as well and there are some known viewport preview "bugs".
Nevertheless, we think that there is enough implementation of decals for now to start playing around with them.
Feel free to share your thoughts on use cases, features that you would like to have with decals here.

Regards,
Aram
Title: Re: CoronaDecals playground!
Post by: maru on 2021-10-14, 13:37:30
Did you... Did you just slap a new name on the distance texture mapping for decals that people have already been doing, there are even tutorials online about it, and call it a day?
No, this is a completely new feature, unrelated to Corona Distance. The underlying technical solution is very different.

Quote
One of the MAIN things about proper decals is that they need to have displacement and by the looks of it you didn't even think about that.
Can you please explain what exactly you mean by that?
Projecting a decal onto a surface with displacement is supported.
Projecting a decal with its own displacement is supported too.

Quote
Again half a year for pretty much nothing can't wait for the new tone mapping in 2028 and proper working converter in 2038.
Let me quote: "Wow absolutely nothing to say here."

Also, please remember that this feature is included in a daily build of Corona, which means that:
- it is still a work in progress
- we are currently collecting user feedback about it to make it better

If you have a specific vision how a perfect decal feature would work for you, please do share it so that we can improve.



Title: Re: CoronaDecals playground!
Post by: Jvincentrs4 on 2021-10-14, 19:48:21
I think over all it is a great start, I do see what people mean about the overriding displacement.  Here is a quick example nothing fancy a ground from megascans and a decal from megascans.

But this is also based on ones thinking of Decal. If we are thinking of this like a sticker on a surface then I would say it is very close to working as it should. Example you have a sticker you place that sticker on you window that
has dirt on it the sticker takes the displacement of the dirt on the window.

Now if the hope and I think what some people are thinking is this would be like two geometries as in example three.

Test_01 I have both displacements on and it does project to the ground but it removes the displacement from the soil texture
Test_02 Removed the displacement from the cloth and the texture wraps to the dirt displacement (Sticker or Decal) 
Test_03 Made geo from the cloth texture and now you have a interaction like you would expect in this case or close to it.


I don't think what has been done is useless just for specific conditions and still Rad. Lets be positive progression always takes time.

Sorry to add one thing I there should be an addition to map around something. Say you are doing a decal that wraps 360 around a cylinder there does not seem to be support for this
currently maybe some work around but would be nice to have the option to have different decal types. 

Jimmy
Title: Re: CoronaDecals playground!
Post by: Ondra on 2021-10-15, 15:40:48
if I understand it right as "the displacement from decal should be added on top of the original displacement, not replace it", that is very easy to do, and can be added as a mode
Title: Re: CoronaDecals playground!
Post by: Jvincentrs4 on 2021-10-15, 17:38:23
Ondra

I think that would be cool. I think then Maybe it would be more like people have in mind.

Great work.
Title: Re: CoronaDecals playground!
Post by: LorenzoS on 2021-10-15, 17:50:55
Hi,
Cdecals works as proiection as i can see, a checbox for proiection/normal_to_surfaxes or somting similar i think it will be usefull.
Title: Re: CoronaDecals playground!
Post by: Jvincentrs4 on 2021-10-15, 19:39:53
Great Example this is what i was talking about having based on normals would be great. Any Curved surface gets very odd.
Title: Re: CoronaDecals playground!
Post by: romullus on 2021-10-15, 20:08:47
if I understand it right as "the displacement from decal should be added on top of the original displacement, not replace it", that is very easy to do, and can be added as a mode

I think there's too much ambiguity in the words "on top" and "replace", so i draw some picture. What i, and i think many others, expected from decals, that it could work like in a, b and c examples. a - only decal is mapped, b - only target is mapped and c - both are mapped (i'm talking only about displacement here). Currently we have a and b, but not c.

I think some people also asked for d - where displacements are mathematically added through some blend modes. This can be useful in some cases, but i think it's not crucial to have it right now.
Title: Re: CoronaDecals playground!
Post by: Ondra on 2021-10-16, 01:46:34
if I understand it right as "the displacement from decal should be added on top of the original displacement, not replace it", that is very easy to do, and can be added as a mode

I think there's too much ambiguity in the words "on top" and "replace", so i draw some picture. What i, and i think many others, expected from decals, that it could work like in a, b and c examples. a - only decal is mapped, b - only target is mapped and c - both are mapped (i'm talking only about displacement here). Currently we have a and b, but not c.

I think some people also asked for d - where displacements are mathematically added through some blend modes. This can be useful in some cases, but i think it's not crucial to have it right now.

C is how it was always supposed to look, if it does not, that means a bug got in at some point and we will fix it.
D would still be doable if requested
Title: Re: CoronaDecals playground!
Post by: marchik on 2021-10-16, 02:14:54
if I understand it right as "the displacement from decal should be added on top of the original displacement, not replace it", that is very easy to do, and can be added as a mode

I think there's too much ambiguity in the words "on top" and "replace", so i draw some picture. What i, and i think many others, expected from decals, that it could work like in a, b and c examples. a - only decal is mapped, b - only target is mapped and c - both are mapped (i'm talking only about displacement here). Currently we have a and b, but not c.

I think some people also asked for d - where displacements are mathematically added through some blend modes. This can be useful in some cases, but i think it's not crucial to have it right now.

C is how it was always supposed to look, if it does not, that means a bug got in at some point and we will fix it.
D would still be doable if requested

I think D case with simple addition in Screen or Add mode will be essential in the cases that I showed above in video, when a decal with a small displacement in the form of e.g. moss is layed on a surface with a strong displacement, for example, rocks

at the moment I'm trying to issue a request for a modifier for custom geometry, which I wrote about in the main discussion topic of daily builds, but so far I've been overwhelmed with work)


Title: Re: CoronaDecals playground!
Post by: romullus on 2021-10-16, 10:44:23
C is how it was always supposed to look, if it does not, that means a bug got in at some point and we will fix it.
D would still be doable if requested

That's great news! I'm looking forward for displacement issues to be fixed and method D introduced when/if possible.
Title: Re: CoronaDecals playground!
Post by: burnin on 2021-10-16, 12:23:49
So is now parallax mapping also considered?
Title: Re: CoronaDecals playground!
Post by: romullus on 2021-10-17, 15:19:42
All the footprints are decals scattered with Corona scatter. There's a thousand of them, lots of overlapping, yet no visible signs of artifacts from displacement. Performance drops quite significantly, but still stays at acceptable level.  So far, i'm impressed.
Title: Re: CoronaDecals playground!
Post by: aaouviz on 2021-10-17, 15:36:03
All the footprints are decals scattered with Corona scatter. There's a thousand of them, lots of overlapping, yet no visible signs of artifacts from displacement. Performance drops quite significantly, but still stays at acceptable level.  So far, i'm impressed.

Very cool and very promising.

Footprints! Such a good use of this new feature, I'm excited to see what else the community comes up with :)
Title: Re: CoronaDecals playground!
Post by: NicolasC on 2021-10-17, 15:44:13
Very nice and smart example, Romullus ! I love it :)
Title: Re: CoronaDecals playground!
Post by: romullus on 2021-10-17, 22:12:17
Hopefully someone else will join the party - playing with decals is seriously fun :] Here's another one from me - lazy house. Just a box with bricks material and windows decals scattered on top. I was pleasantly surprised to find that even AO works with decals (dirt leaks under windows).
Title: Re: CoronaDecals playground!
Post by: burnin on 2021-10-17, 23:11:18
Right on - so many holes :D (why I asked, if parallax mapping is considered now)

How about vector displaced decal w/ light/emission material inside? Does that work?

'tis gonna be a whole another level
Title: Re: CoronaDecals playground!
Post by: marchik on 2021-10-18, 08:11:52
All the footprints are decals scattered with Corona scatter. There's a thousand of them, lots of overlapping, yet no visible signs of artifacts from displacement. Performance drops quite significantly, but still stays at acceptable level.  So far, i'm impressed.
Decal matrerial contains full set of maps including color/rough/normal? or you somehow made Corona to use only displacement channel?
Title: Re: CoronaDecals playground!
Post by: romullus on 2021-10-18, 10:37:34
Yes, decals are mapped with the same texture set as ground material, only displacement map is unique.

or you somehow made Corona to use only displacement channel?

There was loophole to do exactly that in the first build, but unfortunately it was fixed in the latest daily.
Title: Re: CoronaDecals playground!
Post by: romullus on 2021-10-18, 10:40:45
How about vector displaced decal w/ light/emission material inside? Does that work?

Didn't try it myself, but i've heard that light material and self illumination are working with decals just fine. I wouldn't be too much surprised to find that vector displacement is possible too :]
Title: Re: CoronaDecals playground!
Post by: marchik on 2021-10-18, 16:18:19
Yes, decals are mapped with the same texture set as ground material, only displacement map is unique.

or you somehow made Corona to use only displacement channel?

There was loophole to do exactly that in the first build, but unfortunately it was fixed in the latest daily.
but i think in some cases there will be problems with texture coordinates with this approach if not using triplanar) i think we need to make a request for "displacement only" option
 
Title: Re: CoronaDecals playground!
Post by: romullus on 2021-10-18, 16:53:56
I'm agree with you. Option to project selected maps is already requested and acknowledged by the team.
Title: Re: CoronaDecals playground!
Post by: lupaz on 2021-10-18, 17:25:04
if I understand it right as "the displacement from decal should be added on top of the original displacement, not replace it", that is very easy to do, and can be added as a mode

Wow! This would be a great improvement over the layered material, which AFAIK cannot do that.

Very exciting to see the examples Romulus!
Title: Re: CoronaDecals playground!
Post by: Dionysios.TS on 2021-10-20, 17:32:36
All the footprints are decals scattered with Corona scatter. There's a thousand of them, lots of overlapping, yet no visible signs of artifacts from displacement. Performance drops quite significantly, but still stays at acceptable level.  So far, i'm impressed.

Wow, I am impressed too!
Due to the DR's problems during the last releases, I still can't install the last daily build for production. Can't wait to put my hands on it! :D

Thanks for your efforts as always.

Dionysios -
Title: Re: CoronaDecals playground!
Post by: Ondra on 2021-10-26, 22:06:27
How about vector displaced decal w/ light/emission material inside? Does that work?

Didn't try it myself, but i've heard that light material and self illumination are working with decals just fine. I wouldn't be too much surprised to find that vector displacement is possible too :]

light emission, self illumination is working

vector displacement unfortunately not - all advanced displacement properties are taken from the base layer
Title: Re: CoronaDecals playground!
Post by: Frood on 2021-10-27, 09:03:59
light emission, self illumination is working

Light emission (using a light material as decal material) works only with restrictions:

The entire mesh receiving the decal gets turned into lights. Projecting a light material onto some car model creates 1:1 the triangle count of the car of lights. I expect that some hit depth/count parameter (if technically possible) could resolve this.

Directionallity does not work, seems to be zero regardless of the light materials value, same with other light material settings like visibility (which is obviously a technical restriction).

Backfaces get a pitch black decal. Here as well, hit count may solve it. No idea if it could be handled otherwise.


Good Luck



Title: Re: CoronaDecals playground!
Post by: cgiout on 2021-10-27, 11:33:28
Hi guys. Don't know if this is exactly the purpose of this feature but since right now i can apply decals by planar mapping, is in the plans to include different kind of mapping such as cylindrical and spherical or UVW mapping?
It could be very useful instead of adding layers to materials. Quick and easy.

Second consideration: decals doesn't change reflection behavior of surfaces to which decal is applied to. Is is correct? Is there some way to affect reflection glossiness of the surface by the use of decal?

Thanks
Raf

Title: Re: CoronaDecals playground!
Post by: burnin on 2021-10-27, 21:01:43
How about vector displaced decal w/ light/emission material inside? Does that work?

Didn't try it myself, but i've heard that light material and self illumination are working with decals just fine. I wouldn't be too much surprised to find that vector displacement is possible too :]

light emission, self illumination is working

vector displacement unfortunately not - all advanced displacement properties are taken from the base layer

light emission, self illumination is working

Light emission (using a light material as decal material) works only with restrictions:

The entire mesh receiving the decal gets turned into lights. Projecting a light material onto some car model creates 1:1 the triangle count of the car of lights. I expect that some hit depth/count parameter (if technically possible) could resolve this.

Directionallity does not work, seems to be zero regardless of the light materials value, same with other light material settings like visibility (which is obviously a technical restriction).

Backfaces get a pitch black decal. Here as well, hit count may solve it. No idea if it could be handled otherwise.


Good Luck

Yes, those are quite hard to solve efficiently, why I asked. I'd also like to see/know how glass, translucency, subsurface, layered, ray-switcher, shadow catcher...  complex shaders behave.

Then, since decals are a hack (and almost exclusively used for exteriors), so could be shaders; are now any plans to expand some in a way that'll be more user friendly (uber-like) and handle decals better (ie. single sheet SSS, 2-sided, parallax mapping...)?

Finally, how soon or late can C4D users expect to taste it?


:)
Keep up the good work!
Title: Re: CoronaDecals playground!
Post by: TEV09 on 2021-10-31, 18:07:14
Decals are amazing, I wish we had separate button at the Corona Toolbar for CDecal object and the ability to add corona displacement modifier on top of CoronaDecal object, or simple override displacement spinners in CDecal parameters itself

P.S. And maybe in the future it will be cool to have an opportunity to assign "Corona Decal Modifier" to a custom geometry with proper UV coordinates, creating a "projection shell" to project for example stitches on the fabric, using one long stripe of polygons, detached from the original mesh

"Corona Decal Modifier" is a great idea! I imagined what it might look like (look at the attachment).
Title: Re: CoronaDecals playground!
Post by: romullus on 2021-11-09, 20:42:25
Decals are fun!

(https://forum.corona-renderer.com/index.php?action=dlattach;topic=34613.0;attach=156342;image)
Title: Re: CoronaDecals playground!
Post by: marchik on 2021-11-10, 03:30:12

P.S. And maybe in the future it will be cool to have an opportunity to assign "Corona Decal Modifier" to a custom geometry with proper UV coordinates, creating a "projection shell" to project for example stitches on the fabric, using one long stripe of polygons, detached from the original mesh

"Corona Decal Modifier" is a great idea! I imagined what it might look like (look at the attachment).

Guys, any chance to bring this to life? it can be really useful in many cases, if you are interested I can provide more examples.
Title: Re: CoronaDecals playground!
Post by: LorenzoS on 2021-11-10, 09:21:04
Quote
is in the plans to include different kind of mapping such as cylindrical and spherical or UVW mapping?
up
that would be very useful.
Title: Re: CoronaDecals playground!
Post by: romullus on 2021-11-10, 10:26:44
I don't get the logic behind requests to make decals as modifier. Can someone explain me, how it would be different from having uvw map modifier and layered material? Maybe i'm missing something?
Title: Re: CoronaDecals playground!
Post by: LorenzoS on 2021-11-10, 10:52:11
..to solve for example that limitation:
https://forum.corona-renderer.com/index.php?topic=34613.msg190985#msg190985

yes can use layered material, but decal is mutch more simple.
Title: Re: CoronaDecals playground!
Post by: Ondra on 2021-11-10, 11:11:31
but that is not related to a modifier, right?
What you want is a projection mesh, not modifier, right?
Title: Re: CoronaDecals playground!
Post by: LorenzoS on 2021-11-10, 11:13:55
Quote
but that is not related to a modifier, right?
yes
Quote
What you want is a projection mesh, not modifier, right?
yes
Title: Re: CoronaDecals playground!
Post by: LorenzoS on 2021-11-10, 11:27:13
Quote
What you want is a projection mesh
Sorry Ondra, if you means a projection mesh like geopattern, no.
Decals shoud project on mesh
 or perpendicularly to mesh
 or following a UVW map (witothout ripeat obviously).
Title: Re: CoronaDecals playground!
Post by: romullus on 2021-11-10, 11:45:10
..to solve for example that limitation:
https://forum.corona-renderer.com/index.php?topic=34613.msg190985#msg190985

yes can use layered material, but decal is mutch more simple.

Decals are much simpler to use because they are separate object. By turning them to modifier, you basically would lose all the benefits, like ability to use decals on unlimited number of objects, an option to use separate decal material, freedom to independantly move decal in scene. I don't see what you would gain in return, other than you already can do with uvw map and layered material.
Title: Re: CoronaDecals playground!
Post by: LorenzoS on 2021-11-10, 18:03:48
romullus i agree with you, decals should not be turned to modifier,
but in my opinion decals should have the option to be affected by UVW map (not on repeat and not on scale).
Title: Re: CoronaDecals playground!
Post by: marchik on 2021-11-11, 03:03:31
..to solve for example that limitation:
https://forum.corona-renderer.com/index.php?topic=34613.msg190985#msg190985

yes can use layered material, but decal is mutch more simple.

Decals are much simpler to use because they are separate object. By turning them to modifier, you basically would lose all the benefits, like ability to use decals on unlimited number of objects, an option to use separate decal material, freedom to independantly move decal in scene. I don't see what you would gain in return, other than you already can do with uvw map and layered material.

I just meant a Decal modifier (in addition to Decal object) that will turn any custom mesh into a decal instead of basic box/plane, which will be projected onto other objects along the normals of this custom mesh, and not a modifier on the base object, this gives the advantage of allowing you to use custom UV coordinates for the decal and increase the number of possible use cases.

Unlike layered material, this will allow you not to use the second channel of UV coordinates, quickly change the position of the decal in the viewport, and ofcourse apply it to several meshes at once

PS check the attachment
Title: Re: CoronaDecals playground!
Post by: LorenzoS on 2021-11-11, 09:22:52
Quote
...... which will be projected onto other objects along the normals of this custom mesh
exactly what Decals lacks to be nearly perfect.

Quote
I just meant a Decal modifier (in addition to Decal object) that will turn any custom mesh into a decal instead of basic box/plane, which will be projected onto other objects along the normals of this custom mesh
to avoid introducing an additional Decal object, it may be sufficient to insert a checkbox in the current Decals to choose the projection mode of the UVW map applied to the mesh (the UVW map must not be applied to the decals)

Title: Re: CoronaDecals playground!
Post by: romullus on 2021-11-11, 10:42:14

I just meant a Decal modifier (in addition to Decal object) that will turn any custom mesh into a decal instead of basic box/plane, which will be projected onto other objects along the normals of this custom mesh, and not a modifier on the base object, this gives the advantage of allowing you to use custom UV coordinates for the decal and increase the number of possible use cases.

Unlike layered material, this will allow you not to use the second channel of UV coordinates, quickly change the position of the decal in the viewport, and ofcourse apply it to several meshes at once

PS check the attachment

Oh, i see what you mean. Yeah, i agree, that's an interesting idea, but you have to keep in mind that we'd need to deal with projection cage here. In your specific example, it is esentially still a planar projection, but with more complicated meshes you may easily end up with unexpected results, where projection would be stretching, or projecting onto itself. Such decals would be nowhere near as fail-proof as they are now and we may end up with situation, where support have to deal with bunch of false bug reports, "my UVs are perfect, so why my decals are fucked up?" - not everyone knows the difference between UVs and projection, as you can see from this topic alone. Look, i don't want to speak too much against your proposal, i already have been accused in advocating for Corona team too much, i think it's an interesting idea and it's worth to be considered, but it might be not as simple as it seems from a first look. Anyway, it's for the team to decide if it's worth the hassle.

BTW, if you go as far as detaching polygons from target mesh, you already have a decal, you just need to add push modifier to it with small positive value to avoid overlapping, assign decal material with opacity, maybe throw in Corona ray switch material to disable shadowing and you have perfect decal. This technique is nothing new, it has been used for ages in CGI. It might be even slightly faster to render than CoronaDecal, because there's no need for layered material anymore.
Title: Re: CoronaDecals playground!
Post by: marchik on 2021-11-11, 18:46:08

BTW, if you go as far as detaching polygons from target mesh, you already have a decal, you just need to add push modifier to it with small positive value to avoid overlapping, assign decal material with opacity, maybe throw in Corona ray switch material to disable shadowing and you have perfect decal. This technique is nothing new, it has been used for ages in CGI. It might be even slightly faster to render than CoronaDecal, because there's no need for layered material anymore.

yeah, I use this approach of course (otherwise where would I get these screenshots:D) the only thing missing is 2 displacements interactions, including negative values for the decal, that's why I made  a request for decals in the "most wanted feature" topic a long time ago, and now they are finally here, just a little bit left.

And let's be honest, decals in their current form are also not absolutely fail-proof for a beginner who has not encountered them, I am personally ready to prepare a post for the Corona blog on how to straighten UVs! :D

Title: Re: CoronaDecals playground!
Post by: LorenzoS on 2021-11-11, 19:08:20
I am sending this post not to insist but only to clarify my proposal if it is feasible.

The result I would like to obtain is the one done with the layered material, the Decal should have an option that constrains the projection to the unwrap map applied to the cylinder.
Title: Re: CoronaDecals playground!
Post by: Dalton Watts on 2021-11-11, 23:39:14
I'll put the suggestions I've made on Daily Builds Discussion here since they're (mostly) related to Corona Decals:

- Will Corona Decal Order function be implemented?
Just like how Vray 5 decal order works where higher numbers mean top decals and vice versa.

- Added the option to drop bitmaps from Windows Explorer directly into our material slots
This function is great but although not entirely Corona Decal related, another improvement would be also letting you drag and drop any bitmap from Windows Explorer to the CoronaDecal's mask source map slot (while automatically assigning the mask source to map). I reckon this could be much more complicated to implement as I suspect this could be more an Autodesk issue but IMHO it would be much better than drag and drop to slate material editor and then drag to mask source map slot. 1 step vs 2 steps.

This last suggestion could be useful for any Corona Object that has an option for a map to be loaded (CFractal Texmap for example).

Title: Re: CoronaDecals playground!
Post by: aaouviz on 2021-11-22, 15:36:49
How about an option to use hidden decals?

I'm using them as road markings, but they're quickly becoming a bit busy in my scene and making selection of other objects a bit harder. I'd like to hide them but not lose their functionality.

Thanks :)
Title: Re: CoronaDecals playground!
Post by: Rhodesy on 2021-11-24, 11:01:16
Just to confirm I'm doing it right. The only way currently to get a decal that doesnt have displacement placed on top of a displaced material is to add a solid white map to the displacement channel of the decal? Seems to be the case even when the replace base disp checkbox is ticked. If so is it possible to have Corona do that automatically internally without having to add the map manually? Also means that the light material used in the quick example file must inherit the displacement from the base layer as there is no option to add a displacement map in to the light material.   

Sorry if I've overlooked this in the thread previously.

Cheers
Title: Re: CoronaDecals playground!
Post by: aaouviz on 2021-12-07, 12:42:01
Hi all,

I just wanted to share that I'm loving Decals.

At first I was skeptical but now I'm really, really, enjoying having them. I've been using them on a big project the past month or so and I can't have seen myself produce these results so well with any other workflow.

They're stable, predictable, helpful, fast and now irreplaceable.

That is all. A big thanks to the developers!
Title: Re: CoronaDecals playground!
Post by: rowmanns on 2021-12-07, 16:40:20
Just to confirm I'm doing it right. The only way currently to get a decal that doesnt have displacement placed on top of a displaced material is to add a solid white map to the displacement channel of the decal? Seems to be the case even when the replace base disp checkbox is ticked. If so is it possible to have Corona do that automatically internally without having to add the map manually? Also means that the light material used in the quick example file must inherit the displacement from the base layer as there is no option to add a displacement map in to the light material.   

Sorry if I've overlooked this in the thread previously.

Cheers
Hi,

Sorry for the late reply. We have this logged and will investigate :)

Rowan

(Report ID=CRMAX-1161)
Title: Re: CoronaDecals playground!
Post by: Jpjapers on 2021-12-09, 23:38:02
Ive been on a live project since june and im itching to update from V6 to v7 finally but also i cant wait to have a play around with decals in a daily. It would have saved me many hours of manual UVS adding seams and patches to huge canvas tents.

One test im yet to see is how they work with glass. Ive been doing alot of stuff recently with layered materials to put paint and gilded text on the back side of windows.
Just a thought for anyone looking to play around, it would be great to see how it works on the back face of glass (facing outward so the people on the street can see) but also if its possible to use layered materials as decal maps?
Title: Re: CoronaDecals playground!
Post by: Feodor on 2021-12-10, 00:09:08
I really want the decals to work with CoronaMultiMap
It also suggests the function of color mixing as in Photoshop.
Title: Re: CoronaDecals playground!
Post by: aaouviz on 2021-12-10, 08:45:59
Ive been on a live project since june and im itching to update from V6 to v7 finally but also i cant wait to have a play around with decals in a daily. It would have saved me many hours of manual UVS adding seams and patches to huge canvas tents.

One test im yet to see is how they work with glass. Ive been doing alot of stuff recently with layered materials to put paint and gilded text on the back side of windows.
Just a thought for anyone looking to play around, it would be great to see how it works on the back face of glass (facing outward so the people on the street can see) but also if its possible to use layered materials as decal maps?

Hi,

This is actually the first thing I tested and it worked perfectly! Was a great addition to a coffee shop frontage.

I wanted to share it here but never got around to it.
Title: Re: CoronaDecals playground!
Post by: romullus on 2021-12-10, 11:40:58
I think it's a bug - if decal object gets scaled beyond 100%, it won't be visible from the other side of refractive surface, but you can scale it below 100% and even to negative values and everything works fine. Tested on real refraction and on thin shell mode - it's the same.
Title: Re: CoronaDecals playground!
Post by: Jpjapers on 2021-12-10, 12:04:18

<snip>

Hi,

This is actually the first thing I tested and it worked perfectly! Was a great addition to a coffee shop frontage.

I wanted to share it here but never got around to it.

Oh thats awesome thanks
Title: Re: CoronaDecals playground!
Post by: GeorgeK on 2021-12-13, 12:53:41
I think it's a bug - if decal object gets scaled beyond 100%, it won't be visible from the other side of refractive surface, but you can scale it below 100% and even to negative values and everything works fine. Tested on real refraction and on thin shell mode - it's the same.

Thanks Romulus, reporting it for further consideration.

(Report ID=CRMAX-1185)
Title: Re: CoronaDecals playground!
Post by: aaouviz on 2022-01-10, 11:21:31
Any support for 'stacking' decals? I notice the one on top doesn't necessarily render on top of the others... the 'top' decal seems to currently be determined by which was moved last
Title: Re: CoronaDecals playground!
Post by: Ondra on 2022-01-10, 12:29:05
that is a bug and will be fixed.
Title: Re: CoronaDecals playground!
Post by: aaouviz on 2022-01-11, 16:18:54
Hi,

The 'fit to assigned mtl' is VERY useful.

Would it be possible to also get the same function but for 'fit to assigned mask'?

In my mind, this makes a lot of sense.

Thanks guys :)
Title: Re: CoronaDecals playground!
Post by: harumscarum on 2022-01-15, 11:49:47
Amazing feature!
However would it be possible to add blending modes (Darken, Multiply, Color Burn, etc.)
Also "Include" model would be very useful
Title: Re: CoronaDecals playground!
Post by: romullus on 2022-01-15, 13:46:45
Also "Include" model would be very useful

Include/exclude is already possible.
Title: Re: CoronaDecals playground!
Post by: harumscarum on 2022-01-20, 14:42:30
Include/exclude is already possible.
Thanks. I was confused by "exclude" button, but there is include option once you click it

Let me suggest another feature.
I use it to project satellite images of exact sizes and currently it just adjust proportions of the CoronaDecals, but it would be very useful to set real size (per pixel size)
Title: Re: CoronaDecals playground!
Post by: scionik on 2022-01-20, 18:28:48
Include/exclude is already possible.
Thanks. I was confused by "exclude" button, but there is include option once you click it

Let me suggest another feature.
I use it to project satellite images of exact sizes and currently it just adjust proportions of the CoronaDecals, but it would be very useful to set real size (per pixel size)

+1 I like your idea
Title: Re: CoronaDecals playground!
Post by: swedgedesign on 2022-01-20, 22:54:22
I'm loving using decals to populate environments. Is it possible to add this function to an initial state and then the decal follows the deformation of the base object? 

i.e. Projects decal on frame 0, texture is essentially baked on the surface and deforms accordingly - looking for cloth use cases in animation
Title: Re: CoronaDecals playground!
Post by: rowmanns on 2022-01-26, 17:45:41
I think it's a bug - if decal object gets scaled beyond 100%, it won't be visible from the other side of refractive surface, but you can scale it below 100% and even to negative values and everything works fine. Tested on real refraction and on thin shell mode - it's the same.
Hi,

This is fixed in todays daily. You can grab it here: https://forum.corona-renderer.com/index.php?topic=33839.msg194357#msg194357

Cheers,

Rowan
Title: Re: CoronaDecals playground!
Post by: Jpjapers on 2022-02-23, 00:47:51
Just a query, as i havent had chance to test this feature yet. Can you make the decals tile? Is it purely dependant on the planes UVs for placement?
It got me thinking about stitch lines in fabric and i was just wondering how easy they would be to achieve with decals.
Title: Re: CoronaDecals playground!
Post by: Neil Cross on 2022-03-15, 12:40:46
Decided to give decals a go. Excuse the gruesome.
Title: Re: CoronaDecals playground!
Post by: surojgurungptea on 2022-04-08, 01:14:06
Hey Is CoronaDecal still availabe? I only see CFractal, CProxy, CScatter and CVolumeGrid.
Thank you.
Title: Re: CoronaDecals playground!
Post by: rowmanns on 2022-04-08, 09:29:00
Hey Is CoronaDecal still availabe? I only see CFractal, CProxy, CScatter and CVolumeGrid.
Thank you.
Hi,

You need to install a v8 Release candidate build for that: https://forum.corona-renderer.com/index.php?topic=33839.msg196936#msg196936

Rowan
Title: Re: CoronaDecals playground!
Post by: aaouviz on 2022-04-13, 06:50:42
I'm still getting issues with decals stacked on top of one another. Corona has no idea which to render and it seems to render them at random, or whichever I moved last.

I'm using RC5, I thought this was fixed? (However, the scene and decals were created in earlier beta, is this the problem?)

Any help much appreciated :)


Edit: Please disregard this! I think I had a double surface issue happening and causing problems! Sorry.
Title: Re: CoronaDecals playground!
Post by: nauticus25 on 2022-05-11, 15:26:34
Just a query, as i havent had chance to test this feature yet. Can you make the decals tile? Is it purely dependant on the planes UVs for placement?
It got me thinking about stitch lines in fabric and i was just wondering how easy they would be to achieve with decals.

+1 for this. Use case is for diagonal hatch marks painted on pavement. I have several different sized areas to fill and currently need to make different materials for each one. Ideally, I would have one base material (6" wide stripe, 18" wide gap) that can be applied to every CoronaDecal no matter what size it is.

On a related note, it would be great to have non-rectangular CoronaDecals as well. Again, for pavement marking. Many parking lot regions are non-rectangular:
(https://i.imgur.com/lpQKdPN.jpg) (https://i.imgur.com/FQSOlNY.jpg)
Title: Re: CoronaDecals playground!
Post by: jeandedesa2019 on 2022-07-10, 09:15:33
When creating for example a teapot and applying a Corona Decal, so far no problem. But when you want to add, for example, drops of water using ChaosScatter to the teapot and to the Corona Decal, the drops of water also appear in the final rendering in the box surrounding the Corona Decal
Title: Re: CoronaDecals playground!
Post by: jeandedesa2019 on 2022-07-10, 09:18:14
Sorry it'not a teapot
Title: Re: CoronaDecals playground!
Post by: romullus on 2022-07-10, 10:16:56
You only need to add the teapot (car, whatever) to the scatter's distribute-on targets list and not the decals, then it should work as you expect it.
Title: Re: CoronaDecals playground!
Post by: romullus on 2022-07-10, 10:27:13
Here's the proof that it works. The scatter (droplets) is distributed on teapot only and not on decals (bird droppings). As you can see the droplets are placed exactly where are they supposed to be.

By the way, you may want to use include/exclude list for decals and include only the car body, or exclude the scatter, otherwise decals will be projected on the droplets themselves, which will look weird.
Title: Re: CoronaDecals playground!
Post by: jeandedesa2019 on 2022-07-10, 10:29:54
Thanks for your answer, but i want to have some water drop effect on my corona decal too
Title: Re: CoronaDecals playground!
Post by: jeandedesa2019 on 2022-07-10, 10:35:13
Sorry, I hadn't seen your answer
Title: Re: CoronaDecals playground!
Post by: romullus on 2022-07-10, 10:40:25
If you will exclude decals from scatter, that doesn't mean it will not scatter droplets over decal, it means it won't scatter droplets on decal helper object itself, which is what you're complaining in your first message. Does that makes sense?
Title: Re: CoronaDecals playground!
Post by: jeandedesa2019 on 2022-07-10, 10:42:13
I exclude decal to scatter, is now very good. Thanks a lot
Title: Re: CoronaDecals playground!
Post by: romullus on 2022-07-10, 10:45:20
I exclude decal to scatter, is now very good. Thanks a lot

Glad to help you!
Title: Re: CoronaDecals playground!
Post by: fabio81 on 2022-08-25, 13:39:01
Hopefully someone else will join the party - playing with decals is seriously fun :] Here's another one from me - lazy house. Just a box with bricks material and windows decals scattered on top. I was pleasantly surprised to find that even AO works with decals (dirt leaks under windows).

impressive! did you get some displacement maps to get this effect?
Title: Re: CoronaDecals playground!
Post by: romullus on 2022-08-25, 14:49:24
Decal textures for this rendering are from Substance Source: https://substance3d.adobe.com/assets/allassets?q=facade&u=facade There are lots of useful decals over there.
Title: Re: CoronaDecals playground!
Post by: fabio81 on 2022-08-25, 15:37:29
Decal textures for this rendering are from Substance Source: https://substance3d.adobe.com/assets/allassets?q=facade&u=facade There are lots of useful decals over there.

wow!

I hadn't tried decals like this yet!
How did you get the dirt under? have you added an AO and multiplied on the diffuse channel?
I'm on 4D cinema :)

thanks
Title: Re: CoronaDecals playground!
Post by: fabio81 on 2022-08-25, 16:07:03
Perfect!

even with Ambient occlusion!
only the way to pierce the glass would be missing but you would see the wall ..
Title: Re: CoronaDecals playground!
Post by: romullus on 2022-08-25, 16:10:03
How did you get the dirt under? have you added an AO and multiplied on the diffuse channel?
I'm on 4D cinema :)

As far as i recall, that's exactly how i did it. The host program doesn't matter in this case, since everything was done with the power of Corona :]
Title: Re: CoronaDecals playground!
Post by: romullus on 2022-08-25, 16:12:31
Perfect!

even with Ambient occlusion!
only the way to pierce the glass would be missing but you would see the wall ..

I think it's solvable with some DIY hacks. For example you could use OSL with parallax mapping to have illusion of depth. Not sure if that's available in C4D though.
Title: Re: CoronaDecals playground!
Post by: romullus on 2022-10-05, 00:19:45
Feature request - an option to limit decals on user defined material IDs would be nice to have.
Title: Re: CoronaDecals playground!
Post by: shortcirkuit on 2023-02-27, 01:39:35
hi devs - can you use a decal and bend it on a curved surface?  ie dirt map on a pot plant?  Theres a fucntion for vray but not for corona
Title: Re: CoronaDecals playground!
Post by: TomG on 2023-02-27, 13:48:47
hi devs - can you use a decal and bend it on a curved surface?  ie dirt map on a pot plant?  Theres a fucntion for vray but not for corona

Not possible in current versions - this was a new addition to V-Ray in the last hotfix, and is not something added in Corona, at least not yet.
Title: Re: CoronaDecals playground!
Post by: brr on 2023-03-12, 13:10:19
Hello Corona devs and Corona users,

I think it would be great to have more control over plugged textures via CoronaMultiMap with CoronaDecal.
Why?

For example, right now I have a project where I need to brand 10 different objects which have different sizes. Decal texture and its pattern scale stays the same – it looks like barricade tape (red/white) and it differs only by length.
So in such case it has no sense to prepare a set of different textures only because the length differs, it has sense to use one tiled part.
It also has sense to control the object properties with one shader.

Because Decal element has no tiling option build in (and I can not apply UVW mapping on it), I decided to create such construction:

Texture 1,2,3,4,5 (with different tiling option) -> CoronaMultiMap -> CoronaMaterial. And wanted to define the specific texture via ObjectGBuffer ID, which works perfect with classic polygons, but does not work with Decals. Material modifier also does not work in this case.

Please, look at my attachment image.

It would be great in the future to be able to control the texture through Decal G-Buffer ID.

I would also be very grateful if you tell me if there are any workarounds for now...

Best regards.
Title: Re: CoronaDecals playground!
Post by: romullus on 2023-03-12, 13:57:25
I think in your particular case the simplest solution would be to use real-world mapping - unfortunately decals does not support RW mapping either. Overall, i fully agree with you that decals needs to have some sort of IDs to allow precise control in multi-material, multi-map usage.
Title: Re: CoronaDecals playground!
Post by: jasond on 2023-03-13, 13:18:39
For example, right now I have a project where I need to brand 10 different objects which have different sizes. Decal texture and its pattern scale stays the same – it looks like barricade tape (red/white) and it differs only by length.
So in such case it has no sense to prepare a set of different textures only because the length differs, it has sense to use one tiled part.
It also has sense to control the object properties with one shader.

Because Decal element has no tiling option build in (and I can not apply UVW mapping on it), I decided to create such construction:

I created a similar pattern for black and yellow caution tape and just like you wish coronadecal could tile as we use this tape frequently. The only way I've managed to get it work is either create a plane the height/width you want and set a UVW map to the correct size. Another way is to set up a layered material and add UVW to that with the correct size. It automatically tiles.

Would definitely be easier if the decal had a tile option after picking / setting the initial size as well as an option to bend around curves without stretching.
Title: Re: CoronaDecals playground!
Post by: Aram Avetisyan on 2023-03-15, 08:59:44
Hello Corona devs and Corona users,

I think it would be great to have more control over plugged textures via CoronaMultiMap with CoronaDecal.
Why?

For example, right now I have a project where I need to brand 10 different objects which have different sizes. Decal texture and its pattern scale stays the same – it looks like barricade tape (red/white) and it differs only by length.
So in such case it has no sense to prepare a set of different textures only because the length differs, it has sense to use one tiled part.
It also has sense to control the object properties with one shader.

Because Decal element has no tiling option build in (and I can not apply UVW mapping on it), I decided to create such construction:

Texture 1,2,3,4,5 (with different tiling option) -> CoronaMultiMap -> CoronaMaterial. And wanted to define the specific texture via ObjectGBuffer ID, which works perfect with classic polygons, but does not work with Decals. Material modifier also does not work in this case.

Please, look at my attachment image.

It would be great in the future to be able to control the texture through Decal G-Buffer ID.

I would also be very grateful if you tell me if there are any workarounds for now...

Best regards.

This is reported now, thank you.

(Internal ID=1077400719)
Title: Re: CoronaDecals playground!
Post by: brr on 2023-03-16, 13:34:25

This is reported now, thank you.

(Internal ID=1077400719)

Thank you! Hope this will be improved in v10




I created a similar pattern for black and yellow caution tape and just like you wish coronadecal could tile as we use this tape frequently. The only way I've managed to get it work is either create a plane the height/width you want and set a UVW map to the correct size. Another way is to set up a layered material and add UVW to that with the correct size. It automatically tiles.

Would definitely be easier if the decal had a tile option after picking / setting the initial size as well as an option to bend around curves without stretching.

Thanks for the reply! Sorry, I don't get it :) Could you please make some screenshots to show what exactly you mean?



--------------
@all:
it is really impressive that we can also work with decals in 3d mode via triplanar function.I didn't saw this example here before. If I missed it, please excuse me.
Please look at my attachment.

----------------------------------------------------
UPDATE:

While experimenting a little bit more with triplanar and decal techniques, I observed some interesting behavior. When applying the same decal principle to a positively oriented object (max angle degree =180), such as a simple box, the back decal appears more greyish in color. Smoothing groups do not seem to have any impact on this issue. However, when I apply a chamfer modifier, all faces with decals start to look good.
Why is this happening?

Please, look at my second attachment - looks like a bug.mp4
If anyone needs the test scene, I can provide it.

Thanks in advance.
Title: Re: CoronaDecals playground!
Post by: brr on 2023-06-21, 14:17:00
Hello Corona Renderer team,

I understand that you have a lot going on with the upcoming release of Corona 10, but I wanted to ask if there is any way to use Corona Decal with alpha from texture saved as for example PNG for the Corona Decal?
This would greatly simplify and speed up the creation of decals, such as text decals or decals with complex shapes.

Please take a look at my image example in attachment.
In my shader, I have a PNG texture with alpha channel, where I attempted to use this alpha. Connecting it to the opacity slot didn't yield any results, and the red color represents the base color which is behind the texture.


I also wanted to ask if you have reviewed the information in my previous post, where I highlighted a potential issue at the end of that post ("UPDATE" section).
I hope that these observations will be taken into consideration, and that the Corona Decal features will become even better and more versatile.

Thank you in advance!
Title: Re: CoronaDecals playground!
Post by: romullus on 2023-06-21, 15:27:38
Please take a look at my image example in attachment.
In my shader, I have a PNG texture with alpha channel, where I attempted to use this alpha. Connecting it to the opacity slot didn't yield any results, and the red color represents the base color which is behind the texture.

You need to set mono channel output to Alpha, then it should work. Alpha source selector has different purpose.
Title: Re: CoronaDecals playground!
Post by: brr on 2023-06-21, 17:17:04
Please take a look at my image example in attachment.
In my shader, I have a PNG texture with alpha channel, where I attempted to use this alpha. Connecting it to the opacity slot didn't yield any results, and the red color represents the base color which is behind the texture.

You need to set mono channel output to Alpha, then it should work. Alpha source selector has different purpose.

YESS! romullus! it works :)
Apha Source: Image alpha for direct preview in viewport with Corona Decals
Mono Channel Output: Alpha + plugged to Opacity color for decal mask itself.

Thank you !
Title: Re: CoronaDecals playground!
Post by: romullus on 2023-06-21, 19:22:20
You're welcome! :]