Chaos Corona Forum
Official Stuff => News => Topic started by: Ondra on 2014-01-26, 14:05:26
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I've added new modes to the ambient occlusion shader to allow excludes/includes for the occlusion, either by list, or on the same object basis:
(http://i.imgur.com/oNlborG.jpg)
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Good ;)
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Just perfect! It is often necessary.
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Great !
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Useful feature! Thank you!
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You keep adding features, that I've been asking other engine developers for year, like it's no problem!
Amazing KM, keep it up!
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Great !!!
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its good, Thank you!
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Smart AO.. :D Perfect
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In MR you have another way of setting up AO. There is the default feature like you illustrate (put a AO shader in the diffuse slot), but the second one is pretty neat. It only creates AO where there's no direct light and gives a realistic approach of using AO because it only appears on indirect illumination spots. This can be found under the "special effects" tab of the A&D shaders.
See attachment for the difference. It would be very nice to see such a feature for AO in Corona.
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In MR you have another way of setting up AO. There is the default feature like you illustrate (put a AO shader in the diffuse slot), but the second one is pretty neat. It only creates AO where there's no direct light and gives a realistic approach of using AO because it only appears on indirect illumination spots. This can be found under the "special effects" tab of the A&D shaders.
See attachment for the difference. It would be very nice to see such a feature for AO in Corona.
That is not true, when using AO as special effect of Arch&Design material, it still appears everywhere, not only in shadow. Only difference being that special effect one has soft fixed spread, and by default, occluded color is not completely black.
You can do a simple test by setting AO shadow color for example to vibrant green, and increasing radius. You will see that AO distribution is same in lit areas as it is in shadows.
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Rawalanche,
You're true about that, see attachment.
but I'd like to address the fact that AO shouldn't be used (or far less) at places with direct light. An online manual posted somewhere on this forum tells a same story.
http://www.slideshare.net/ozlael/hable-john-uncharted2-hdr-lighting (http://www.slideshare.net/ozlael/hable-john-uncharted2-hdr-lighting) (page 173 (and some pages before and after to explain the principle))
The AO in the special effects roll-out of the A&D shader deals with this quite clever I think unless the fact that it actually generates AO the same way as you stated but with a better refinement.
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AO in Corona is meant only as a dirt simulation, not GI simulation, and as such, is independent on the actual lighting. You should never, ever get into a situation where you need to "enhance" the GI solution with AO in Corona.
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How about inverse AO? I tend to use it to detail edges of things such as metal objects with rust or scratches on the edges.
Combined with being able to plug in a map you can get some pretty nice effects.
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already done, check the invert checkbox
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Nice about all those new modes.
Is it possible to have 'only other objects' and 'exclude list' working at the same time or is it a dropdown menu ?
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it is a radio button
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Thank you very much, this is exactly what I asked here http://forum.corona-renderer.com/index.php/topic,2527.0.html (http://forum.corona-renderer.com/index.php/topic,2527.0.html) Your efficiency is respected)
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AO in Corona is meant only as a dirt simulation, not GI simulation, and as such, is independent on the actual lighting. You should never, ever get into a situation where you need to "enhance" the GI solution with AO in Corona.
Exactly... AO in Corona is meant to be primarily used as a tool to create procedural weathering effects and similar things. It is not meant to enhance accuracy of Global Illumination solution, as GI in Corona is very accurate. Applying AO to pictures rendered in Corona will actually ruin your picture instead of enhancing it.
Some people make mistake of creating very high albedo materials, like absolutely white walls for example, and aside from slowing down rendering a bit, it also removes most of the contact shadows, which people then try to bring back with AO. That is extremely bad approach and prime example of how things should NOT be done ;)
And that does not apply only to Corona. It applies to most of the renderers out there. These days, only renderer i can think of that has so bad GI solution it needs AO to enhance lost contact shadows is Mental Ray.
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I absolute agree with Rawalanche!!
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Hey! I have a question..
Is there any way to create invisible object that generates AO?
if I turn down the opacity - AO dissapears aswell if I turn off Renderable checkbox..
In my workflow I really need not-renderable objects to generate AO is there any way to achieve it?
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Yes there is, just make a second render with CTexmap Renderpass and CoronaAO in it, then add the AO in post.