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paulhart
03-16-2018, 12:03 PM
I like NPR work (surprise) and I routine like to have a AO pass, and others to composite as needed to create NPR effects. How to get just a AO pass? and other passes, not on the 'official' list in the Render Panel. There used to be Master Plugins to set them aside to be picked up on the output side. Am I missing something. I saw one video, that showed a Occlusion Node going into the bottom slot of the Output Material Node, but can't fine that video nor that setup anywhere???
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Further thoughts . . . I have db&wTools exr, so I can save everything off that way, but I still don't see how to get an AO pass. Something I am missing, yet again?

paulhart
03-16-2018, 02:56 PM
Just read on this forum: [Seems to be an annoying omission on Newtek's part, not addressed by any Plugin?? Anybody??]

"I use dpont's Node Pixel Filter to get an ambient occlusion custom render pass out and also DPedges to add extra bevels to otherwise flat geometry.

Is there still no way of achieving this things natively in 2018?

Nope! (was the answer, next post)

- - - Updated - - -

Just read on this forum: [Seems to be an annoying omission on Newtek's part, not addressed by any Plugin?? Anybody??]

http://forums.newtek.com/member.php?68104-Otterman
"I use dpont's Node Pixel Filter to get an ambient occlusion custom render pass out and also DPedges to add extra bevels to otherwise flat geometry.

Is there still no way of achieving this things natively in 2018?

Nope! (was the answer, next post)

paulhart
03-16-2018, 05:27 PM
I found the video, that generates the AO slot, at the bottom of the Output Node, working for 2018.0.2. It does require adding the Occlusion Node to each surface that I want, individually, instead of creating a "Global Image Filter" as Master Plugin that can be referenced at Output as a Buffer. But this works for now. I also know about Global Materials, as I have that Plugin, but it is a different work flow consideration. I will consider this one 'solved' for now, pending further contributions from my 'legion' of Reply contributors... ;->)
https://www.youtube.com/watch?v=P7QO6_ODrsg

Snosrap
03-17-2018, 08:36 AM
Yeah there needs to be a global solution- native.

adk
03-17-2018, 05:22 PM
The create custom buffers slot is great, but a missed opportunity if you can't have global access and overrides of some sort like shadermeister.
100+ materials in a scene means you're forced to save out a separate object and scene for AO - which is the antithesis of what a custom buffer workflow should ultimately be.
So yeah I wholeheartedly agree that there needs to be a better way / solution to this.

MonroePoteet
03-18-2018, 10:07 AM
I'm definitely no compositing expert, and it's a total hack, but maybe it would be worth experimenting with the "shadows" cast by the new LW2018 Environment light. I've been experimenting, and don't really have anything significant to post, but something like this might be worth a try:


Create your scene and surfaces as you want
Once done, use Save=>Package Scene to copy the Scene and all Objects to someplace else (I use C:\Temp, or create an "FakeAmbientOcclusion" subfolder for this copied content)

The reason for Package Scene is so you don't accidentally save your Objects with the Shadow Density Alpha Channel (below), or mess up your desired Backdrop / Environment as described below

In the new scene, do the following:

Disable all Lights
Add an Environment Light and create a new AOBufferGroup for diffuse output
Disable whatever Backdrop / Environment you've got and set the Backdrop color to White
Disable Global Illumination (or experiment with it on / off)
In Surface Editor, select the first Surface, hold down SHIFT and select the last, selecting them all
In the Shading Model tab, set the Alpha Channel on all of them to "Shadow Density"

Render out a couple of frames, take a look at the Alpha Channel in the Image Viewer, see if it's anything you could use


140747

By increasing and decreasing the Intensity of the added Environment Light, you can get more or less "shadows" cast by the pure-white environment, and perhaps adjust it to be a faked global Ambient Occlusion channel.

Here's a couple of simple frames from this process:

140743 Final Render from Original Scene
140744 Final Render buffer from AOBufferGroup_EnvironmentLight
140745 Diffuse Direct buffer
140746 Alpha Channel

As I said, I'm definitely no expert, but *might* be worth experimenting with. As long as you're careful to use the Package Scene to copy all objects and the scene elsewhere, you can effect all surfaces and the backdrop without messing up your original scene.

Good luck!
mTp

MonroePoteet
03-18-2018, 03:22 PM
For whatever reason, I didn't upload the sample scene file for the previous post. Here it is. Note that the objects aren't saved with their Shadow Density setting, so you'll have to do that to reproduce the results.

mTp

adk
03-27-2018, 04:02 PM
For whatever reason, I didn't upload the sample scene file for the previous post. Here it is. Note that the objects aren't saved with their Shadow Density setting, so you'll have to do that to reproduce the results.

mTp

I'm not sure that I understand what you're trying to do here mTp. If you're packaging up another scene along with objects then creating an AO pass is trivial. Make one AO material or custom buffer and apply to all.

If you have an existing scene with 100's of objects / surfaces and all you want is AO on a global scale, without messing up your existing scene, then the current way of achieving that (without another scene / objects) is a pain. Global Materials does this but in a different way to Shadermeister - which was a great way to do global overrides.

oliverhotz
03-27-2018, 06:48 PM
The create custom buffers slot is great, but a missed opportunity if you can't have global access and overrides of some sort like shadermeister.
100+ materials in a scene means you're forced to save out a separate object and scene for AO - which is the antithesis of what a custom buffer workflow should ultimately be.
So yeah I wholeheartedly agree that there needs to be a better way / solution to this.

ODTools... one click solution

adk
03-30-2018, 04:31 PM
ODTools... one click solution

Thanks Oliver ... I have your awesome tools and pretty much feel like this :foreheads

Seems that there's a new awesome tool every week, I simply need to keep up with the pace of your development :D