Why Does the shadow materials does not allow the occlusion intensity curve??

[Anonymous]

Hello all, 

Everything is in this post's title.

Iet me explain:

In order to produce VR review (automotive) I would like to fake an "animated ambient" occlusion in OpenGL.

inside of the vehicule, when the door is close, then the door panel is dark, because of this precomputed ambient occlusion, the problem is that when we play the opening animation, the ambient occlusion doesn't match.

The Only work-around in order to have something much realistic, is to play a geometry switch at the end of the opening animation... but it's not quite efficient, because switching géometry can't be animated smoothly... it is basically 1 or 0.

Then I discovered that I can animate the "Occlusion Intensity" value into materials... maybe it is the way, but we need in this case to animate 2  Objects for playing this animation and of course using the shadow material, in order to have:

- 1 geometry for door material (without any occlusion)

- 1 duplicated geometry for the closed door occlusion (shadow material 1) - like a layer over the first geometry which contains shadow / occlusion

- 1 duplicated geometry for the opened door occlusion (shadow material 2) like a layer over the first geometry which contains shadow / occlusion

and basically when the door opens the "Occlusion Intensity" of the shadow material 1 has to fade out (1 to 0), and the "Occlusion Intensity" of the shadow material 2 has to fade in (0 to 1).

Theory is perfect... so I decided ton engage the plan... and then I cried !!!

just because the shadow material is the Only material without this Fu*****ng "Occlusion Intensity" channel! 

Why!!???

Is there any way to do what I want to do?

Please... help!

[Anonymous]

So- what failed?

Occlusion Intensity will control how dark the shadow is- not animate its movement.

I'm stuck in version 2017.0.2, so maybe there is now an animatable Occlusion Intensity in 2018?  I only see the Occlustion Color RGB as animatable, so I can't try your theory.

I don't know if this is an option for you, but if you are able to Raytrace, you can set the global  method to Precomputed Illumination (Render Settings > RT Quality), which will see the baked shadows, and then change only (per material) what has to have a moving shadow through it's attributes- Rayracing > Override Illumination Mode- change to Precomputed + Shadows.

For example- a car on a moving turntable will have the lower RT settings, but the platform material will have an override with a higher RT setting so that the shadows update as the lighting changes.

[Anonymous]

Hi Dawn, and many thanks for your answer.

You're right when you said: "Occlusion Intensity will control how dark the shadow is- not animate its movement." and that's the point.

I'm pretty aware about the impossibility of animate an object's occlusion, and I'm not trying to do that.

I'm trying to make a smooth transition between to different occlusion in OpenGL only (because of creating a VR project Review😞

I have to set my scene graph as defined here:

My animated group contains:

- First of all, my door panel geometries (A), which are shaded without any baked occlusion

- Secondly, I have created a group which contains:

• my duplicated door panel geometries , which are shaded with a shadow material (B) and baked with a "closed door" ambient occlusion (we only see the occlusion on this geometries like this was a shadow layer... so if you set the occlusion intensity to 0, then geometries are invisible)
• my duplicated door panel geometries , which are shaded with a shadow material (C) and baked with a "opened door" ambient occlusion (we only see the occlusion on this geometries like this was a shadow layer... so if you set the occlusion intensity to 0, then geometries are invisible)

what I am trying to do is to animate not the occlusion itself, but those two shadow materials (B & C) with their occlusion intensity channel, in order to fade Out the A one and Fade In the B one when door is opening, and reversly when the door is closing, showing the two faded occlusions over the shaded visible geometries (A)

unfortunatelly, in the curves Editor, this occlusion intensity channel seems to be able for all material kind, except for the shadow material, and I wonder why!!?? because this occlusion intensity channel is accesible directly into the material tab 

Is this an omission from Vred developper's team, or is this a voluntary fact?!

Does an Update in order to activate this occlusion intensity channel for shadow material will be done?

Can anybody tell me the way to animate the occlusion intensity channel for a shadow material?

[michael_nikelsky · Accepted solution]

Hi,

plain and simple answer: it was just forgotten to add as an animatable channel.

That being said, you can achieve the same result by just animating the occlusion color where rgb 1,1,1 is equal to an occlusion intensity of 0. It is not as convenient but should just work fine. 

Kind regards

Michael

[Anonymous]

Thank you Michael for your answer.

Efficient as usual!